Mapping natural capital and ecosystem services in the Nene Valley Mapping Natural Capital and Ecosystem Services in the Nene Valley
Mapping Natural Capital and Ecosystem Services in the Nene Valley
Author: Dr Jim Rouquette Natural Capital Solutions & University of Northampton
Contact details: Dr J.R. Rouquette Natural Capital Solutions Ltd www.naturalcapitalsolutions.co.uk [email protected] Tel: 07790 105375
Report prepared for: Nene Valley NIA Project
Publication date: December 2016
Version: Final
Recommended citation: Rouquette, J.R. (2016). Mapping Natural Capital and Ecosystem Services in the Nene Valley. Report for the Nene Valley NIA Project. Natural Capital Solutions.
Cover image: Sunset over Irthlingborough Lakes and Meadows (John Abbott)
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Mapping Natural Capital and Ecosystem Services in the Nene Valley
Acknowledgements A large number of people contributed to this project. In particular I’d like to thank Stella Watts, Kat Harrold, Duncan McCollin, Janet Jackson and Jeff Ollerton, all from the University of Northampton. Jeff, in particular, oversaw and supported all of the work described in this report and chaired the steering group. Stella collated all of the biodiversity records described in Section 2.3 and gathered together many other data sets and GIS layers. Thanks to Nicholas Head and Kat Harrold who endured the task of manually mapping hedgerows in GIS, and to Gilles Jean-Louis who carried out preliminary work on hedgerow mapping and on the historic analysis (Chapter 3). Thanks also to Oliver Burke and Heather Proctor of the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire who were members of the steering group. Thanks to all project partners on the Nene Valley NIA project: the University of Northampton, Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire, Natural England, River Nene Regional Park, Northamptonshire County Council, North Northants Joint Planning Unit, RSPB, and Environment Agency. Funding for this project was provided by Defra, with additional funding from Natural England, Sciencewise, the University of Northampton, and Natural Capital Solutions Ltd. Finally, thanks to Alison Holt (Natural Capital Solutions) and Jeff Ollerton who reviewed the draft version of this report.
Further Info A summary report accompanies this full technical report and is available from: http://www.naturalcapitalsolutions.co.uk/previous-projects/case-study-2/
For further information on the Nene Valley Nature Improvement Area please visit: http://www.nenevalleynia.org/
First published December 2016 © /IP Natural Capital Solutions Ltd & University of Northampton
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Mapping Natural Capital and Ecosystem Services in the Nene Valley Executive summary
The Nene Valley occupies most of Northamptonshire and Peterborough. The area is dominated by arable farmland, interspersed by urban areas, but at its heart lies an extensive series of flooded gravel pits forming a network of wetland habitats. These areas are home to abundant wildlife and have been recognised internationally for their importance through their designation as a Special Protection Area (SPA) under the EU Birds Directive. The Nene Valley faces increasing pressures from human development as most of the area falls within a zone highlighted for significant growth over the next few years. This will place considerable pressure on the catchment, but also presents an opportunity to achieve conservation of biodiversity and ecosystem services at a landscape scale. The Nene Valley was designated as a Nature Improvement Area (NIA) in 2012, a flagship nature conservation initiative launched by the UK Government to promote landscape-scale conservation.
The natural environment underpins our wellbeing and economic prosperity, providing multiple benefits to society, yet is consistently undervalued in decision-making. Natural capital is the stock of natural assets, including habitats, water and biodiversity that produces a wide range of benefits for people. These benefits are known as ecosystem services and include, for example, food, timber production, regulation of flooding and climate, pollination of crops, and cultural benefits such as aesthetic value and recreational opportunities. Adopting the natural capital and ecosystem services approach is a key policy objective of the UK Government and central to Defra’s new 25 year plan. Here I quantify, map and where possible provide a monetary value of the natural capital and ecosystem services of the Nene Valley. Gaining a spatial perspective on the variation in values across the study area using maps provides much additional insight and is at the forefront of ecosystem services research at present.
This report presents the findings of a major project to identify, map and value natural capital and ecosystem services across the Nene Valley. The aims were to highlight the key benefits provided by the natural environment, to increase understanding of the interdependencies between the natural environment, people and the economy, and to help planners and decision makers protect, enhance and restore the natural environment for the benefit of both people and wildlife.
The first task was to map the natural capital assets of the Nene Valley and was an essential prerequisite for the subsequent ecosystem services maps. A detailed land-use and habitat map was created by classifying MasterMap polygons into Phase 1 habitat types using a range of data sources. A map of hedgerows was also produced by manually identifying hedgerows from aerial photographs, and revealed that there are approximately 10,000 Km of hedgerows and tree lines in the study area. Maps were also produced showing biodiversity: over 275,000 biological records held by a range of recording organisations were collated for six taxonomic groups (flowering plants, butterflies, moths, dragonflies and damselflies, hoverflies, and bees and wasps). Species richness (the number of species at each location) was calculated and mapped and these were then converted into density maps showing the density of species across the study area.
Habitat in the Nene Valley in the 1930s was mapped and compared to the current situation (2010s). Semi- natural grassland was the dominant habitat type in the 1930s, occupying 59.9% of the area. By the 2010s, semi-natural grassland had declined to just 2.9%, a decline of 95%. Arable had increased to 50.3% of the land area (an increase of 115%), with improved grasslands occupying a further 18.9%. Woodland and built- up areas and gardens had both increased by >60%.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley
Maps were developed for 11 different ecosystem services: carbon storage, noise regulation, local climate regulation, air purification, water flow, water quality, pollination, agricultural production, tranquillity, accessible nature, and green travel. The capacity of the natural environment to deliver those services (the current supply) was mapped and, wherever possible, the local demand (beneficiaries) for each service was also mapped. Each map was created by running a Geographic Information System (GIS) based model, based on the EcoServ GIS toolkit developed by the Wildlife Trusts, but with a number of modifications to better suit the situation in the Nene Valley. In addition, bespoke models were created for several ecosystem services. In all cases the models were applied at a 10m by 10m resolution to provide extremely fine scale mapping across the area. The models are indicative (showing that certain areas have higher capacity or demand than other areas) and highlight areas of high and low provision and the pattern of capacity (supply) and demand for each ecosystem service.
Once each service was mapped individually, maps were generated of the overall supply and demand of all services. These were created for both average scores and as hotspots based on area. The supply maps highlighted the importance of woodlands and the River Nene corridor at delivering multiple ecosystem services. The river corridor is also effective at bringing habitats delivering high levels of ecosystem services right into the heart of urban areas, and this is particularly prominent in Peterborough, Northampton and Kettering. The demand maps clearly highlighted the importance of the urban areas in driving demand, with the very highest demand from parts of Northampton and Peterborough.
The monetary value of a range of ecosystem services across the Nene catchment has also been mapped. This was for: agricultural and orchard production; greenhouse gas balance (taking into account emissions from agriculture and carbon sequestration); pollination; and expenditure on recreation. Comparing across ecosystem services, it was apparent that the value of recreational visits far outweighed the value of all other ecosystem services in the Nene catchment. Publicly accessible areas have the greatest overall value. In total the annual flow of ecosystem services in the Nene Valley NIA were valued at £109M each year and £300M across the wider Nene Valley, with the majority of this derived from the value of recreational visits. On average, each hectare of land delivers £2,639 of services per year in the core NIA and £1,769 of services across the whole study area. This assessment has only considered a small number of ecosystem services on which it is possible to provide a monetary value, hence the true value of the natural environment will be considerably higher.
This project has produced maps at a resolution that allows the examination of the trade-offs and synergies in the provision of multiple ecosystem services, even across small distances. This work can be used to highlight strategic locations for delivering multiple benefits, by continuing with practices in hotspot areas, and evaluating how enhancement can be achieved in coldspots. The maps are being used as evidence in the planning system and the project team worked with local planning authorities to embed ecosystem services into planning policies, such as the newly adopted North Northamptonshire Joint Core Strategy. They can also be used to engage with stakeholders, to model future scenarios, in ecosystem accounting, and as a basis for setting up Payments for Ecosystem Services (PES) schemes and other ecosystem markets. This report outlines a number of PES schemes and other opportunities for promoting natural capital and ecosystem services that may be possible in the Nene Valley. It ends by describing projects that could take the work forward, particularly focussed around further integration of ecosystem services into the planning and development sector, opportunity mapping, and through undertaking a Natural Capital Investment Plan.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley Contents
Executive summary ...... iii Contents ...... v List of maps ...... vii List of tables ...... viii List of figures ...... viii
1. Introduction ...... 1 1.1 The Nene Valley and its Nature Improvement Area ...... 1 1.2 What are natural capital and ecosystem services? ...... 3 1.3 Project aims and report structure ...... 4
2. The baseline – natural capital assets ...... 5 2.1 Approach to mapping habitats ...... 5 2.2 Habitats and conservation status ...... 5 2.3 Biodiversity ...... 16
3. The changing habitats of the Nene Valley: a historical perspective over 80 years ...... 29 3.1 Introduction ...... 29 3.2 Approach ...... 29 3.3 Results ...... 30 3.4 Discussion ...... 33
4. Modelling and mapping ecosystem services...... 35 4.1 Introduction ...... 35 4.2 Carbon storage capacity ...... 36 4.3 Noise regulation capacity ...... 38 4.4 Noise regulation demand ...... 40 4.5 Local climate regulation capacity ...... 42 4.6 Local climate regulation demand ...... 44 4.7 Air purification capacity ...... 46 4.8 Air purification demand ...... 48 4.9 Water flow capacity ...... 50 4.10 Water flow demand ...... 52 4.11 Water quality capacity ...... 54 4.12 Water quality demand ...... 56 4.13 Pollination capacity ...... 58 4.14 Pollination demand ...... 60 4.15 Agricultural production capacity ...... 62 4.16 Tranquillity capacity ...... 64 4.17 Accessible nature capacity ...... 66 4.18 Accessible nature demand ...... 68
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4.19 Green travel capacity ...... 72 4.20 Green travel demand ...... 74
5. Delivering multiple ecosystem services ...... 76 5.1 Overall supply of ecosystem services ...... 76 5.2 Hotspots of ES supply ...... 76 5.3 Overall demand for ecosystem services ...... 79 5.4 Hotspots of ES demand ...... 79
6. Monetary valuation ...... 81 6.1 Introduction ...... 82 6.2 Agricultural and orchard production ...... 83 6.3 Greenhouse gas balance...... 88 6.4 Pollination ...... 96 6.5 Recreation ...... 99 6.6 Overall valuation and discussion ...... 103
7. Natural capital and ecosystem services in the Nene Valley ...... 106 7.1 Hotspots and coldspots, trade-offs and synergies ...... 106 7.2 Some applications of natural capital and ecosystem services mapping ...... 108 7.3 Payment for Ecosystem Services Schemes and other opportunities ...... 109 7.4 Further work ...... 111
References ...... 114
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List of maps Map 1: Nene Valley location map……………………………………………………………………………..……………….…….………. 2 Map 2: Broad habitats……………………………………………………………………………………………….……….…………..……….. 7 Map 3: Nature conservation designations………………………………………………………………………………..………………. 8 Map 4: Key habitat areas………………………………………………………………………………………………………………………….. 10 Map 5: Hedgerows…………………………………………………………………………………………………………………………..………. 11 Map 6: Agricultural land classification…………………………………………………………………………………………….………… 13 Map 7: Agri-environment agreements…………………………………………………………..…………………………………………. 14 Map 8: River ecological classification………………………………………………………..……………………………………….….…. 15 Map 9: Plant species richness……………………………………………………………………………..…………………………….……… 22 Map 10: Butterfly species richness ……………………………………………………………….…………………………………………. 23 Map 11: Moth species richness ……………………………………………………………………………….………………………………. 24 Map 12: Odonata species richness ………………………………………………………………………………………………….………. 25 Map 13: Syrphidae species richness ……………………………………………………………………………………………………….… 26 Map 14: Bees and wasps species richness ……………………………………………………………………………………..…….….. 27 Map 15: Land-use and habitats in the 1930s…………………………………………………………………………………….………. 31 Map 16: Land-use and habitats in the 2010s ………………………………………………………………………………………….… 32 Map 17: Carbon storage capacity…………………………………………………………………………………………………….….……. 37 Map 18: Noise regulation capacity………………………………………………………………………………………………….….…..… 39 Map 19: Noise regulation demand………………………………………………………………………………………………….………… 41 Map 20: Local climate regulation capacity……………………………………………………………………………………..……….… 43 Map 21: Local climate regulation demand…………………………………………………………………………………………….….. 45 Map 22: Air purification capacity……………………………………………………………………………………………………….…..… 47 Map 23: Air purification demand……………………………………………………………………………………………………………… 49 Map 24: Water flow capacity………………………………………………………………………………………………………………….… 51 Map 25: Water flow demand: flood risk……………………………………………………………………………………………….….. 53 Map 26: Water quality capacity………………………………………………………………………………………………………….…..… 55 Map 27: Water quality demand………………………………………………………………………………………………………………… 57 Map 28: Pollination capacity………………………………………………………………………………………………………….……….… 59 Map 29: Pollination demand…………………………………………………………………………………………………………………..… 61 Map 30: Agricultural production capacity…………………………………………………………………………………………………. 63 Map 31: Tranquillity capacity………………………………………………………………………………………………………………….… 65 Map 32: Accessible nature capacity………………………………………………………………………………………………………..… 67 Map 33: Accessible nature demand – sources model……………………………………………………………………………….. 70 Map 34: Accessible nature demand – sites model…………………………………………………………………………………….. 71 Map 35: Green travel capacity……………………………………………………………………………………………………………….…. 73 Map 36: Green travel demand………………………………………………………………………………………………………………….. 75 Map 37: Average ecosystem service capacity…………………………………………………………………………………………... 77 Map 38: Hotspots of ecosystem service capacity………………………………………………………….……………………..…… 78 Map 39: Average ecosystem service demand…………………………………………………………………………………………... 80 Map 40: Hotspots of ecosystem service demand………………………………………………………….…………………….….… 81 Map 41: Agricultural production value……………………..………………………………………………………………..……..….…. 86 Map 42: Orchard production value…………….……………..………………………………………………………………………..……. 87
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Map 43: Carbon sequestration value……………………..…………………………………………………………………...……..……. 93 Map 44: Value of agricultural emissions…….……………..………………………………………………………………...……..……. 94 Map 45: Greenhouse gas balance……………………..………………………………………………………………..……..…………….. 95 Map 46: Pollination value…………….……………..………………………………………………………………..…………………...……. 98 Map 47: Recreation value……………………..………………………………………………………………..…………………………...... 102
List of tables Table 1: Percentage cover of broad habitat types across the Nene Valley NIA and the buffer zone………….. 6 Table 2: Total biological records collated for each taxonomic group in the Nene Valley NIA plus buffer…… 16 Table 3: Number of locations with biological records for each taxa, total richness across the Nene Valley, mean and maximum richness for each location, and most widespread species recorded… 19 Table 4: Final habitat categories chosen, and the corresponding categories from the Dudley Stamp maps (1930s) and the basemap (2010s)……………………………………………………………………………….……... 30 Table 5: Total annual value of agricultural and orchard production across the study area……………………….. 84 Table 6: Average annual carbon sequestration rate for woodlands in Northamptonshire…………………………. 89 Table 7: Total physical flow of carbon sequestration, agricultural emissions and greenhouse gas balance across the study area……………………………………………………………….…………………………………….. 90 Table 8: Carbon prices from different sources…………………………………………………………………………………………… 90 Table 9: Total value of carbon sequestration, agricultural emissions and greenhouse gas balance across the study area………………………………………………………………………………………………………………….. 91 Table 10: Total value of agricultural and orchard pollination across the study area…………………………………. 97 Table 11: Estimated number of visits and the annual value of these visits………………………………………………. 100 Table 12: Annual value of ecosystem services across the study area and lower-bound estimate of value based on the sensitivity analysis…………………………………………………………………………………. 103 Table 13: Asset value (present value) over 50 years with standard UK Government discounting rates applied……………………………………………………………………………………………………………………………. 104 Table 14: Annual flow of ecosystem services per hectare across the study area……………………………………… 105
List of figures Figure 1: Key types of ecosystem services………………………………………………………………………………………………... 3 Figure 2: Spatial assessment framework used in this report. This is based loosely on the ecosystem services cascade framework developed by Haines-Young et al. (2006) and others………………….... 4 Figure 3: The relative proportion of biological records from different time periods for each taxonomic group……………………………………………………………………………………………………………………..… 17 Figure 4: The number of records in the final dataset, showing only unique species-site combinations recorded from 2000 onwards……………………………………………………………………………………………………. 18 Figure 5: Percentage change in habitat types between the 1930s and 2010s…………………………………………... 33 Figure 6: Annual value of ecosystem services in the Nene Valley NIA plus buffer………………………………..….. 103
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1. Introduction
1.1 The Nene Valley and its Nature Improvement Area The catchment of the River Nene incorporates most of Northamptonshire together with Peterborough and small parts of Cambridgeshire (the location is shown on Map 1). The character and form of the Nene Valley has been intrinsically shaped by interactions between people and the natural environment. At its heart lies an extensive series of flooded gravel pits, created by decades of industrial gravel extraction, but now forming a network of wetland habitats. These areas are home to abundant wildlife and have been recognised internationally for their importance through their designation as a Special Protection Area (SPA) under the EU Birds Directive and as a Site of Special Scientific Interest (SSSI). The remainder of the catchment consists largely of arable farmland and improved grassland, interspersed by urban areas including Northampton, Wellingborough, Kettering, Corby and Peterborough. Relatively few sites away from the SAC have been given nature conservation designations. Nevertheless, fragments of semi-natural habitats remain that have been designated as SSSI or Local Wildlife Sites. The historic and cultural value of the catchment is recognised by a number of Scheduled Monuments and listed buildings. The Nene Valley is also extremely important for the many and multiple benefits that it provides to people. The interactions between people and the natural environment remain of critical importance and it is these interactions that are the basis of the concept of ecosystem services. Furthermore, the Nene Valley faces increasing pressures from human development as most of the catchment falls within an area highlighted for significant growth over the next few years. This will place considerable pressure on the catchment, but also presents an opportunity to achieve conservation of biodiversity and ecosystem services at a landscape scale. The Nene Valley was designated as a Nature Improvement Area (NIA) in 2012, a flagship nature conservation initiative launched by the UK Government to promote landscape-scale conservation. The idea for NIAs was proposed in the Lawton Report (Lawton et al. 2010) as Ecological Restoration Zones and was subsequently taken up by the UK Government in the Natural Environment White Paper (HM Government 2011). The Government selected 12 NIAs to receive a share of £7.5M in funding for three years from 2012- 15 with the aim of “restoring and connecting nature on a significant scale” (HM Government 2011). The Nene Valley NIA was a partnership between the University of Northampton, the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire, Natural England, River Nene Regional Park, Northamptonshire County Council, a number of borough councils, RSPB, and the Environment Agency. It had five key objectives: 1. Growth and development that supports the natural environment 2. Enhance public awareness and sustainable access 3. Improve the ecological status of the river 4. Strengthen the ecological network through farmer engagement 5. Investigate the ecosystem services provided by the Nene Valley The Nene Valley NIA consists of the floodplain of the river from sources to Peterborough and takes up an area of c. 41,500 ha (see Map 1). For the natural capital and ecosystem services assessment described in this report, I assessed the NIA plus a 3Km buffer zone (Map 1). This is more or less equivalent to the whole catchment of the River Nene, to a few kilometres downstream of Peterborough, and has an area of c. 170,000 ha (1700 Km2).
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 1.2 What are natural capital and ecosystem services? The natural environment underpins our wellbeing and economic prosperity, providing multiple benefits to society, yet is consistently undervalued in decision-making. Natural capital is the stock of natural assets, including habitats, water and biodiversity that produce a wide range of benefits for people. These benefits are known as ecosystem services and include, for example, food, timber production, regulation of flooding and climate, pollination of crops, and cultural benefits such as aesthetic value and recreational opportunities. Performing an assessment of ecosystem services is a way of recognising the natural environment for the many and multiple benefits that it provides. The key types of ecosystem services are shown in Figure 1:
Provisioning Regulating Cultural
Products obtained from Benefits obtained from Non-material benefits people
ecosystems environmental processes that obtain from ecosystems regulate the environment e.g. food, timber, water e.g. recreation, aesthetic e.g. air quality, climate regulation, experiences, health and wellbeing
pollination
Figure 1: Key types of ecosystem services
Note that a fourth group of ecosystem services is often recognised, known as the supporting services, and includes functions such as photosynthesis, soil formation, and decomposition. However, these services are nowadays referred to as ‘intermediate services’ or ecosystem processes and are not usually assessed in ecosystem services assessments. Many of these processes are essential in driving the provisioning, regulating and cultural services, but they are not the ‘final services’ from which people directly benefit, and including them would also lead to double-counting the benefits received. Adopting the natural capital and ecosystem services approach is a key policy objective of the UK Government (and worldwide) and central to Defra’s new 25 year plan. Much work is progressing on how to deliver the approach on the ground and how to use it to inform and influence management and decision- making. One of the most important steps is to recognise and quantify ecosystem service delivery (the physical flow of services derived from natural capital) and that is the key part of the project described in this report. It is also possible to provide a monetary valuation (monetary flow) of a number of ecosystem services and this is also described in this report. There is a great deal of interest in quantifying and providing a monetary valuation of ecosystem services, but gaining a spatial perspective on the variation in values across a study area using maps provides much additional insight. Maps are able to highlight hotspots and coldspots of ecosystem service delivery, highlight important spatial pattern, provide much additional detail, and are inherently more user friendly than non-spatial approaches. The approach in this project has therefore been to provide high resolution maps of all ecosystem services (and their values where possible). This is very much at the forefront of ecosystem services research at present.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 1.3 Project aims and report structure This report describes a major project to identify, map and value natural capital and ecosystem services across the Nene Valley. This was undertaken as part of the Nene Valley Nature Improvement Area Project, with funding from Defra and the University of Northampton. The aims are to highlight the key benefits provided by the natural environment, to increase understanding of the interdependencies between the natural environment, people and the economy, and to help planners and decision makers protect, enhance and restore the natural environment for the benefit of both people and wildlife. The conceptual framework for the approach I have adopted is shown in Figure 2. The first task is to map natural capital assets and this work is described in Section 2 of this report. Section 3 then examines the change in landuse and habitats over the last 80 years. Once the natural capital assets have been mapped it then becomes possible to map the ecosystem services that flow from this natural capital. Here I map the supply of 11 different services and the demand for 8 of these services (Section 4), and then combine these maps to show the overall supply and demand for all ecosystem services (Section 5). The final stage is to map the monetary values of those ecosystem services for which it is possible to do so, and this is described in Section 6. The final section of the report (Section 7) discusses the key findings and issues arising from the results, some possible applications of this type of spatial mapping approach particularly with regard to to informing decision making and planning, and ends with a discussion of Payments for Ecosystem Services (PES) Schemes and other opportunities to encourage investment in natural capital and ecosystem services in the Nene Valley.
Map natural capital assets
Shows the extent and distribution of different stocks of natural capital
Map ecosystem service flows
Shows the level and spatial distribution of the production of key ES, or maps showing hotspots and coldspots of multiple ES
Map value of benefits
Shows the distribution in the values of benefits derived from ecosystem services
Figure 2: Spatial assessment framework used in this report.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 2. The baseline – natural capital assets
2.1 Approach to mapping habitats Before the flow or value of ecosystem services can be mapped, it is necessary to obtain an accurate assessment of the current habitats and biodiversity present in the study area – the natural capital assets. To do this I used EcoServ, a toolkit developed by the Wildlife Trusts, with a number of bespoke modifications. This approach uses MasterMap polygons as the underlying mapping unit and then utilises a series of different data sets to classify each polygon to a habitat type and to associate a range of additional data with each polygon. The data that was used to classify habitats is shown in Box 1.
Box 1: Data used to classify habitats in the basemap: MasterMap topography layer OS vector maps
Open space (green infrastructure) data sets for each local council (9 local councils in total). Data highly variable from council to council, so had to be extensively pre-processed to ensure compatibility and usability in EcoServ. BAP habitat – supplied by Northamptonshire and Cambridgeshire Wildlife Trusts, combined
with additional data taken from the National BAP dataset. Required pre-processing to determine if each polygon was BAP quality or not, and to classify each habitat to fit with EcoServ requirements Local wildlife sites obtained from Northamptonshire Wildlife Trust
Land Cover Map 2007 Corrine European habitat data – modified and used to identify quarries, industry and golf courses, and to distinguish arable from pasture
Layer that identified urban areas Ancient Woodland Inventory data
Polygons were classified into Phase 1 habitat types and were also classified into broader habitat groups. I made multiple modifications to the EcoServ programme code to enable improved classification of habitats. Furthermore, upon initial completion the basemap was carefully checked and manual alterations were made in a number of places where miss-classifications had occurred. The basemap was produced for the Nene Valley Nature Improvement Area and 3Km buffer zone (the main study area, as shown on Map 1), plus an additional buffer zone of 3Km to ensure that all maps were accurate right to the edge of the main study area. The final basemap contained 1.43M polygons, each of which was classified to an appropriate habitat type.
2.2 Habitats and conservation status
2.2.1 Broad habitats Table 1 shows the percentage cover of broad habitat types across the Nene Valley NIA and the buffer zone, and these are mapped in Map 2. The core NIA study area (41,500 ha) is dominated by cultivated land and improved grassland (making up c. 67% of the area), but has significant areas of freshwater (5.1%), and
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Mapping Natural Capital and Ecosystem Services in the Nene Valley semi-natural grassland (4.9%) habitats. Built-up areas, gardens and infrastructure (roads, railways, pavements and paths) make up a significant 14.8% of the land area. If the 3Km buffer zone is included as well (with a combined area of c. 170,000 ha) the proportion of freshwater and semi-natural grassland habitats declines considerably, with a marked increase in the proportion of cultivated land and woodland, whilst built-up areas, gardens and infrastructure now occupy 12% of the area.
Table 1: Percentage cover of broad habitat types across the Nene Valley NIA and the buffer zone
Broad habitat NIA NIA plus buffer Cultivated / disturbed land 39.4 49.8 Uncertain agriculture 3.3 2.6 (improved grass or arable) Grassland, improved 24.1 21.2 Grassland, semi-natural 4.9 2.9 Scrub 1.0 0.7 Trees / Parkland 1.7 1.3 Woodland, broadleaved 2.7 3.9 Woodland, coniferous 0.4 0.9 Woodland, mixed 1.1 2.2 Water, fresh 5.1 1.6 Built up areas 5.6 4.1 Infrastructure 3.9 3.2 Gardens and parks 5.3 4.7 Other 1.4 0.9
2.2.2 Nature conservation designations The Upper Nene Valley Gravel Pits, at the heart of the NIA, are considered to be of national and international importance for overwintering birds and have been designated as a SPA and SSSI. Away from this site, only a relatively small amount of the study area has received statutory nature conservation designations. The total amount of land designated as SSSI within the core NIA amounts to 2,052 ha, or 4.9% of the total area, with 3,783 ha (or 2.2%) of the wider NIA plus buffer so designated. In total 1,358 ha, amounting to 3.3% of the NIA, is designated as SPA (1,480 ha or 0.9% of the wider study area). Small additional areas have been designated as SACs or National Nature Reserves, although none of these fall within the core NIA. The location of designated sites is shown on Map 3.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 2.2.3 BAP habitats High quality semi-natural habitats are classed as BAP (Biodiversity Action Plan) habitats. In total 1,189 ha, which represents 2.9% of the core NIA, was assessed to contain BAP quality habitat. In the wider NIA plus buffer area, 5,666 ha or 3.3% of the area was BAP quality. In addition, a number of sites have been named as Local Wildlife Sites, which are sites that are generally considered to contain a good assemblage of species or to be locally important, but do not meet the criteria for national designation. Local Wildlife Sites comprise 2,879 ha or 6.9% of the NIA and 9,131 ha (5.4%) of the NIA plus buffer. The location of all BAP habitat and Local Wildlife Sites is shown on Map 4.
2.2.4 Hedgerows and tree lines Hedgerows and tree lines are important elements of the landscape, often providing the only elements of semi-natural habitat in areas of intensive agriculture, and can be important in linking up and providing wildlife corridors between larger patches of habitat. They also form an important part of the aesthetics of the English countryside contributing to the cultural value of the landscape. The presence of hedgerows and tree lines is not captured on OS MasterMap or the subsequent basemap produced here, hence a separate map of these features was produced for the entire study area. This was achieved using aerial photographs supplied by Natural England, which were orthorectified and georeferenced so that they could be used directly in GIS. The MasterMap Lines database was overlaid and all boundaries where a hedge or tree line was present were manually selected. Urban areas were ignored as it was not possible to tell from the aerial photos which hedges were semi-natural. The final map was fully checked by a second person. The hedgerow and tree lines were also converted to polygons, using the average width of hedgerows in England (2m). The resulting map is shown as Map 5. A relatively dense network of hedgerows and tree lines is evident across most of the study area and this is especially apparent in the western half of the study area. There are fewer hedgerows around Peterborough as ditches and drainage channels take the place of hedgerows on many field boundaries. There are approximately 10,000 Km of hedgerows and tree lines in the NIA and buffer zone.
Mute swans, Summer Leys by Victor Penn
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 2.2.5 Agriculture and environment According to Natural England data, the vast majority of the Nene Valley is classified as Grade 3 agricultural land (Map 6), indicating that it is of moderate quality. Smaller amounts of Grade 2 (higher quality) and Grade 4 (lower quality) land is present in patches, with the Grade 4 land particularly associated with the less well drained land close to the river in the Upper Nene. Agricultural land is of highest quality at the very downstream edge of the study area, downstream of Peterborough, with small amounts of Grade 1 land (highest quality) where the river enters the fens. Natural England also hold data on the uptake of agri-environment schemes and this is shown on Map 7. The vast majority of agricultural land is under some form of environmental stewardship agreement, with 77,665 ha under Entry Level Stewardship across the NIA plus buffer, 32,385 ha under Entry Level plus Higher Level Stewardship, and 2,402 ha under one or both of the Organic Stewardship schemes.
2.2.6 River quality The overall quality (ecological status) of each reach of the River Nene is assessed by the Environment Agency under the Water Framework Directive, and is shown in Map 8. The majority pf the Nene is classified as moderate, but several reaches, particularly in the upper Nene, upstream of Northampton, are classified as poor.
Morning mist, Nene Valley by Melvin Mallard
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 2.3 Biodiversity
2.3.1 Biological records As well as assessing the habitats present across the Nene Valley, information was also collated on biodiversity – the species present in the study area. To do this all accessible biological records held by a range of recording organisations was collected together, including: National Biodiversity Network (NBN) Gateway Northamptonshire Biodiversity Records Centre Cambridgeshire and Peterborough Environmental Records Centre National recording groups for different taxonomic groups Local recording groups and individual local recorders Northamptonshire Natural History Society University of Northampton Records were combined for each taxonomic group and then extensively checked and cleaned to remove duplicates and clipped to the study area boundary. The final number of records for each taxonomic group is shown in Table 2.
Table 2: Total biological records collated for each taxonomic group in the Nene Valley NIA plus buffer
Taxa Number of records Flowering plants 43,658 Butterflies 75,935 Moths 134,356 Odonata 16,196 Syrphidae 4,563 Bees & wasps 807 GRAND TOTAL 275,515
Perhaps the most striking element of Table 2 is the enormous range in the number of records for different taxonomic groups, ranging from over 134,000 moth records to only c. 800 records of bees and wasps. Bees and wasps are clearly highly under-recorded in the Nene Valley (and across the UK), making it difficult to establish the ecology and conservation status of these vital pollinators. Other taxa are, however, well recorded, with a grand total of over 275,000 records for the study area, and this is considered to be a relatively under-recorded part of the country. In addition to the six taxonomic groups shown in Table 2, efforts were also made to collect biological data for bats and birds, but it was not possible to take this forward. Bat records are held by a local recorder, but unfortunately are not released to the public domain. Bird records are held predominantly by BTO, but at the time when the data sets were compiled (2013) there was not a suitable data source equivalent to the other taxonomic groups. This is surprising given that birds are by far the most well recorded group in the country, with enormous volunteer effort put into recording schemes. Data from the Breeding Bird Survey and Wetland Bird Survey was considered, but these provide very detailed data over much smaller areas and
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Mapping Natural Capital and Ecosystem Services in the Nene Valley are not really comparable. BTO have now released the data behind their Bird Atlas 2007-11, and this would be comparable. However, this was not available until relatively recently and it is expensive to purchase (it is the only taxonomic group for which a charge is made).
2.3.2 Historic patterns Biological records have been collected for centuries, indeed the earliest record in our data set dates back to 1799, with a handful more in the 19th Century. However, more systematic biological recording only became established in the last few decades, with recoding schemes set up at different times for different taxa. Figure 3 shows the spread of time periods for the biological records. It shows that there were relatively few records prior to 1980, but a large increase in records for flowering plants and butterflies in the period from 1980-2000 as recording schemes took off. Records for other groups such as Syrphidae (hoverflies) and Odonata (dragonflies and damselflies) became much more extensive even more recently (after2000) as wide public interest in recording these groups developed relatively recently.
100%
80%
60%
40%
20%
0% Plants Butterflies Moths Odonata Syrphidae Bees & wasps
Before 1980 1980-2000 From 2000
Figure 3: The relative proportion of biological records from different time periods for each taxonomic group
2.3.3 The final dataset To map biodiversity across the study area, only data collected from 2000 onwards was used. This date was chosen for two reasons; first comparable extensive records for all taxa are only available from this date (see previous section); and second, the records needed to reflect where species are likely to still occur, and due to land use change, climate change and natural population cycles, data collected from prior to 2000 may be less relevant today. Therefore only records collected after 2000 were retained in the final dataset. The primary focus of this work is in the spread of species across the study area and the species richness of each taxonomic group. Varieties and sub-species were therefore merged, and records where only a family name was provided were removed. The final step was then to remove all occurrences of the same species at the same site (when recorded on different dates). The final dataset therefore contains only unique species at each geographic location. This removed a large number of repeated records (species being recorded at the same site over a number of years) and the final number of unique species-site records is shown in Figure 4.
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352
2,890 Plants 16,196 Butterflies
20,099 Moths
Odonata 11,526 Syrphidae
Bees & wasps
9,098
Figure 4: The number of records in the final dataset, showing only unique species-site combinations recorded from 2000 onwards.
There were 48,708 unique species-site combinations recorded across the NIA and buffer. Note that even though moths made up nearly half (48.8%) of all the records originally compiled, once records of the same species recorded at the same site are removed they accounted for only 23.7% of the unique records. There are now more unique flowering plant records than for any other taxa, although all taxa apart from bees and wasps are well represented in the final dataset.
Common darter (Sympetrum striolatum) by David Harris
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 2.3.4 Species richness The final dataset was imported into a GIS package and used to calculate the species richness (number of species) found at each location. Here a location is defined as a unique grid reference (at 100m resolution), rather than a named site such as a country park, which are usually much larger and may contain several recorded locations. This information was used to determine the mean richness at each location, as well as the maximum richness at any one location, and the total richness across all locations (Table 3). Butterflies were recorded from more unique locations (1735) than any other taxonomic group (Table 3). Moths on the other hand were recorded at relatively few locations (155) despite the large number of records, reflecting the different recording methods used for this group, usually involving placing a moth trap at a specific point. Mean richness per site was highest for moths (74.4) and plants (59.4), but was very similar for each of the other taxa (around 5). Total richness and maximum richness recorded at any one location was also highest for moths and plants, reflecting the relative richness of these groups in the UK. For all taxa, the Nene Valley and buffer contain a relatively high proportion of the total UK list. The three most widespread species recorded in the study area for each taxon are also shown in Table 3. In almost all cases these are indeed very widespread species, although in the bees and wasps it also includes Bombus hypnorum (the tree bumblebee), which is a recent colonizer of the UK (first recorded in the UK in 2001), and records almost certainly reflect interest in the species and its spread.
Table 3: Number of locations with biological records for each taxa, total richness across the Nene Valley, mean and maximum richness for each location, and most widespread species recorded Number of Total Max Mean Most widespread species Taxa locations richness richness richness Stinging nettle Flowering 338 770 280 59.4 Hawthorn plants Creeping thistle Peacock Butterflies 1735 38 33 5.2 Red admiral Large white Large yellow underwing Moths 155 595 382 74.4 Brimstone moth Silver Y Blue-tailed damselfly Odonata 808 27 19 5.8 Common blue damselfly Banded demoiselle Episyrphus balteatus Syrphidae 410 148 77 5.4 Eristalis pertinax Syrphus ribesii Bombus pascuorum Bees & wasps 92 126 26 3.8 Bombus lapidarius Bombus hypnorum
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 2.3.5 Distribution and richness patterns The species richness data were then plotted to reveal patterns of distribution and richness across the NIA and buffer (see Box 2, next page, for further info on this). The final maps produced show the density of species in the study area. These were created by employing a kernel density function in ArcGIS, which calculates the density of species richness in a neighbourhood around each record. The neighbourhood distance (or search radius) was determined based on the first peak spatial autocorrelation distance of each taxon (based on Global Moran’s I statistic). Spatial autocorrelation indicates that data are clustered and is expected in biological data (locations that are close to each other are more likely to share species than locations that are further apart). Differences in spatial autocorrelation distance arise due to different dispersal distances, landscape features and differences in sampling intensity. Hence by picking out the peak spatial autocorrelation distance, data from each taxonomic group was used to select the most appropriate distance based on the spatial pattern revealed by the data. A map was produced for each taxonomic group and these are shown in Maps 9-14. In all cases, red colours indicate the highest density of species, blue colours are the lowest density, with white indicating areas with no records. Some of the key points to emerge from these maps are described below: Almost all of the flowering plant records occur along the floodplain of the river, within the NIA boundary (Map 9). There are two possible explanations for this; either there really are more species along the floodplain as there are more areas of semi-natural habitat in these locations; or this is a sampling artefact and merely reflects where people visit, which may be due to the greater public access close to the river or the perception that these areas are more attractive or more likely to contain greater numbers of interesting plants. Butterfly records are more widely spread throughout the NIA plus buffer (Map 10). There are particular concentrations of sightings around many of the woodlands of the Rockingham Forest, such as Fermyn Woods, Fineshade Woods and Castor Hanglands, which are well known as good butterfly sites, but also a large number of sightings in publicly accessible greenspaces in and around urban areas, especially Corby, Northampton and Kettering. Moths (Map 11) display a very different pattern compared to butterflies, with records from far fewer locations. Richness is very high at some of these locations, but it is likely that this reflects favoured spots for setting up light traps, rather than real differences in species distributions. Odonata (dragonfly and damselfly) records occur almost exclusively along the floodplain of the River Nene, within the NIA boundary (Map 12). This is perhaps not surprising, given the much greater density of water features in these areas. Particular hotspots include the area around Thrapston, Stanwick Lakes, Irthlingborough Lakes and Meadows, Higham Ferrers, Wicksteed Park, and close to the River Nene immediately upstream of Northampton. Records of Syrphidae (hoverflies) are much sparser than the previous groups (Map 13). Hotspots are apparent, but it is highly likely that these reflect locations favoured by the main recorders, so it is difficult to draw many inferences from these. Locations with the highest richness appear to be Bradlaugh Fields in Northampton, around Pitsford Reservoir, and Old Sulehay Forest to the west of Peterborough. The map for bees and wasps (Map 14) is included for completeness, but it is based on so few records that it is not really possible to draw any conclusions from this map.
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Box 2: Mapping biodiversity The biodiversity data can be mapped in a number of different ways. Initially maps were plotted showing each unique record at 100m resolution (based on six-figure grid references). This is shown below for the flowering plants:
This clearly shows the overall distribution of records across the study areas, but it is impossible to gauge whether a single point represents one species or hundreds of species. Hence it is better to plot species richness (the number of different species recorded at each location):
This imparts much more information, although it can be difficult to interpret areas where lots of circles overlap. This can be improved further by plotting the density of records, with a search radius based on the spatial pattern revealed by the data. The final density map for plants is shown on Map 9.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 2.3.6 Concluding comments Using biological records presents a number of challenges. The data are ad hoc occurrence records, not based on a rigorous sample design, and may have been collected for a number of different purposes and in different ways. The data are presence only, meaning that blank areas on a map are not areas where the species of interest does not occur, but rather where there are no records. In addition, the data displays a number of biases – spatial, environmental, temporal and taxonomic. The temporal bias was removed by only including records since 2000, after which time all groups are well represented. The taxonomic bias is evident in the huge range in the number of records for different groups, but it appears that all groups – with the exception of the bees and wasps – are adequately recorded in the Nene Valley to draw some inferences. The spatial and environmental bias is caused by recorders preferring to visit certain locations or certain habitats, rather than recording systematically or randomly over the entire area. This is harder to deal with. It would be possible, and very interesting, to build models that take these biases into account and examine the likely distribution of species in areas where there are currently no records. The approach would be to build models of species richness in areas with data, using habitat, environmental and public access variables as predictors, and taking into account the sample selection biases. The results could then be projected into unsampled areas, and model accuracy tested with new data. Thus for all of the taxonomic groups it is difficult to disentangle the effects of sampling bias from genuine environmental effects. The maps therefore capture both of these elements and should be interpreted with care. However, this adds an additional element of interest, as wildlife watching and recording is an important cultural service and these maps, to a certain extent, highlight locations that are delivering that service. It is apparent that the core NIA is particularly important for many of the taxonomic groups and their recorders, especially for Odonata and flowering plants. The NIA provides both suitable habitat for these taxa and suitable and attractive visitor access for recorders.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 3. The changing habitats of the Nene Valley: a historical perspective over 80 years
3.1 Introduction Land-use and habitats in the UK have changed drastically since the Second World War. During this time period the countryside underwent a period of major intensification and industrialisation, with a rapid rise in the use of artificial fertilizers, pesticides, and machinery, as well as increases in field sizes, drainage of wetlands, reduction in rotations, simplification and homogenization of farm types, and altered cropping patterns from spring sown to autumn sown crops. At the same time there has been a rapid expansion of urban areas and an increase in plantation forestry. These factors taken together have led to the loss of much of the semi-natural habitats of lowland UK, and the fragmentation of remaining patches, resulting in major declines in biodiversity. It has also resulted in changes to the ecosystem services delivered by the land, with a primary focus on agricultural and timber production, but a decline in other ecosystem services. Here I have mapped the land-use and habitats of the Nene Valley NIA plus 3Km buffer using data for the 1930s and compared this to the current situation (2010s). There are a number of reasons for doing so: To establish how land-use has changed and the amount of change of different habitats. To assess changes in the degree of fragmentation and connectivity of habitat patches. To identify previous land-use configurations to aid with the identification of the most suitable locations for habitat restoration. To identify changes in the delivery of ecosystem services over the last 80 years.
3.2 Approach Although historic maps are available dating back several centuries and with newer editions appearing at regular intervals in more recent times, these do not provide any information on habitats, apart from identifying woodlands. Indeed only one source of habitat information is available prior to the 1980s and that is The Land Utilisation Survey of Great Britain, 1933-49. These resulting maps are known as the “Dudley Stamp Maps” after the organiser and instigator of the survey. A scanned and digitised version of the survey was obtained. The digital version of the Land Utilisation Survey classifies habitats into eight different categories. A key challenge when comparing maps from very different sources is the difficulty of matching land cover types between the different surveys. The original definitions of the Dudley Stamp categories were used and compared to the habitat types produced in the basemap described in Chapter 2, and matched as closely as possible. Nine final categories were chosen and Table 4 describes how the habitats from both time-periods fit into these categories. All “meadowland and permanent grass” identified in the Dudley Stamp map was classified as “semi-natural grassland” and no areas were classified in the “improved grassland” category. This is based on the assumption that no agricultural grasslands were improved at that time as they were not receiving inorganic fertilizers. This has been shown to be true in areas with detailed botanical data from the 1930s. Urban areas presented a particular difficulty as these areas were not mapped in any detail in the Dudley Stamp survey. In the Dudley Stamp maps, dense urban areas were classified as “land agriculturally unproductive”, with suburban areas classified as “gardens”, and only large greenspaces within urban areas were marked separately. As there was no obvious way to match this with the categories on the modern
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Mapping Natural Capital and Ecosystem Services in the Nene Valley map, a new category was created of “built-up areas and gardens” containing both the Dudley Stamp categories. For the present day map, all urban and garden categories were combined, along with amenity grassland (e.g. road verges) that were less than 1 ha in size.
Table 4: Final habitat categories chosen, and the corresponding categories from the Dudley Stamp maps (1930s) and the basemap (2010s)
Final categories Dudley Stamp categories Basemap habitats Woodland Forest and woodland Broadleaved woodland Coniferous woodland Mixed woodland Scrub Parkland Arable Arable land Cultivated / disturbed land (excluding allotments) Semi-natural grassland Meadowland and permanent grass Semi-natural grassland (includes neutral, acid and calcareous grassland) Improved grassland - Improved grassland (excluding rough grassland) Heath and marsh Heaths and moorlands Marshy grassland, (includes rough pasture) Rough grassland, Heathland, Mire Swamp Built-up areas and gardens Land agriculturally unproductive Built-up areas, (includes buildings, roads, industry) Infrastructure Gardens & brownfield Gardens (includes allotments) Allotments Amenity grassland < 1 ha Orchards Orchards Orchards Freshwater Water Freshwater Other / unclassified - Other Uncertain Unclassified
Using the new categories, two maps were created representing the 1930s and the 2010s and clipped to the study area boundary. Data was then extracted on the cover of each habitat in each time period for the core NIA and the wider NIA plus buffer, and the change in habitat area was calculated.
3.3 Results A map of habitats in the 1930s is shown as Map 15, with the corresponding map from the 2010s as Map 16.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley Semi-natural grassland was the dominant habitat type In the 1930s, occupying 59.9% of the area of the NIA plus buffer, with arable land occupying 23.4%. Built-up areas and gardens occupied 9.0% and woodland 5.4%. The core NIA was similar, but with more freshwater and built-up areas and less woodland and arable. There were no improved grasslands. In contrast, by the 2010s, arable had increased to 50.3% of the land area, with improved grasslands occupying a further 18.9%. Semi-natural grassland had declined to just 2.9%, whilst built-up areas and gardens had increased to 14.6% and woodland had increased to 8.9% The overall change in cover between the two time periods is shown in Figure 5. This shows that there has been a massive 95% decline in semi-natural grasslands (a loss of 96,800 ha) and an 88% decline in heath and marsh (wetland and rough grazing) habitats across the whole study area. On the other hand, arable has increased by 115% (an increase of 45,700 ha), built-up areas and gardens by 61% and woodland by 63%. Improved grassland has increased from zero to 32,200 ha.
150
100 115
50 61 63
29 20 % change 0
-50
-88 -95 -100 Semi-natural Arable Built-up areas Woodland Freshwater Heath and Orchards grassland and gardens marsh
Figure 5: Percentage change in habitat types between the 1930s and 2010s.
3.4 Discussion The maps and data paint a picture of profound habitat change over the last 80 years. Almost all semi- natural habitats have been lost, replaced predominantly by arable and improved grassland. There has also been an expansion of urban areas and of woodland, particularly of plantation forestry in the 1950-60s. The Nene Valley is certainly not unique in recording these changes as the patterns here have been seen throughout lowland England. Nationally, it has been estimated that unimproved grassland and rough grazing has declined by 91% and woodland has increased by 66% over similar periods, figures that closely match the 95% decline and 63% increase seen here.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley Such profound changes in habitats are almost certain to have had a profound impact on biodiversity in the Nene Valley. As well as direct loss of habitat, remaining habitat patches are smaller and more fragmented with reduced connectivity between wildlife populations. This reduces dispersal between populations, and small and isolated populations are more prone to local extinction. Efforts were made to match the habitats recorded in the 1930s to those from the present day, but there will inevitably be some discrepancies. Habitats were recorded at a much higher resolution in the present study, capturing very small habitat patches. This was not the case in the 1930s, particularly in urban areas, and water was also mapped with less accuracy. In addition, the digitization process led to some further loss of detail for small habitat patches. It is likely that both the built-up / garden and water categories will have been slightly overrepresented in the 1930s map compared to the present day, whereas some smaller habitats such as orchards will have been underrepresented. The exact habitat areas and percentage change reported here are therefore prone to some error. Nevertheless, the overall picture of change is accurate. There are likely to have been major changes in the ecosystem services delivered by the natural environment over the last 80 years. Clearly agricultural production will have increased enormously, along with timber production. However, a number of regulatory services are likely to have declined. The ability of the land to retain water will have decreased considerably, and the impact of habitats on water quality will also have declined. The impact on carbon storage and sequestration is more difficult to predict without a detailed assessment, as gains in carbon through increasing woodland cover will have been offset by losses due to conversion of semi-natural grasslands to arable and improved grassland, which store less carbon. The supply of pollination services is likely to have declined with the loss of semi-natural habitats, but the demand for pollination will have increased considerably as oil-seed rape has become a major component of the farming landscape but was not planted at all in the 1930s. Cultural services will also have been impacted although it is impossible to assess these due to cultural and other changes over the period.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4. Modelling and mapping ecosystem services
4.1 Introduction Mapping the benefits that the natural environment provides to people can follow a number of different approaches and be performed at different spatial resolutions. The approach used here is based on the EcoServ GIS toolkit developed by the Wildlife Trusts, but with modifications and adaptations of many of the EcoServ models to better suit the situation in the Nene Valley. In addition, for several ecosystem services bespoke models were created. The following ecosystem services have being mapped: Carbon storage Pollination Noise regulation Food production Local climate regulation Tranquillity Air purification Accessible nature Water flow Green travel Water quality In all cases the models are applied at a 10m by 10m resolution to provide extremely fine scale mapping across the area. The models are based on the detailed habitat information determined in the basemap. In addition they require lots of other external data sets in order to run, and these data sets are outlined in Box 3. Note, however, that most of the models are indicative (showing that certain areas have higher capacity or demand than other areas) and are not process-based mathematical models. For all of the ecosystem services listed, the capacity of the natural environment to deliver that service – or the current supply – was mapped. Wherever possible, the local demand (beneficiaries) for each ecosystem service was also mapped. This has not, however, been possible for services where the demand is considered to be national or international, such as carbon storage or food production and mapping of local demand does not make sense. Maps have been created for the Nature Improvement Area and 3Km buffer zone shown in Map 1, plus an extended buffer area to the outside. This enhances accuracy right to the edge of the main study area, plus supply and demand from just outside the area that may influence ecosystem services in the study area can be mapped. In all cases the capacity and demand for ES is mapped relative to the values present within the study area.
Box 3: Additional data sets used to model and map ecosystem services:
Digital terrain model UK census 2011 data and Index of Multiple Deprivation data Public Rights of Way data from Northamptonshire and Cambridgeshire Open space (green infrastructure) data sets for each local council (9 in total) Countryside Rights of Way access areas, Sustrans routes and other national routes Land designations – SSSI, NNR, SAC, SPA etc. Defra road and rail noise models Updated Flood Map for Surface Water (uFMfSW) and river flooding maps (Flood Zones 2 and 3) Woodlands for Water national data set WFD data sets from the EA Defra June agricultural statistics and Farm Business Survey CPRE National Tranquillity Data set 2007
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.2 Carbon storage capacity
4.2.1 What is it and why is it important? Carbon storage capacity indicates the amount of carbon stored naturally in soil and vegetation. Carbon storage and sequestration is seen as increasingly important as we move towards a low-carbon future. The importance of managing land as a carbon store has been recognised by the UK government and land use has a major role to play in national carbon accounting. Changing land use from one type to another can lead to major changes in carbon storage, as can restoration of degraded habitats. Carbon is increasingly being given a monetary value and forms the basis of Payments for Ecosystem Services (PES) schemes such as the Woodland Carbon Code.
4.2.2 How is it measured? The EcoServ carbon storage model was used. This model estimates the amount of carbon stored in the vegetation and top 30cm of soil. It applies average values for each habitat type taken from a review of a large number of previous studies in the scientific literature (Cantarello et al. 2011). As such it does not take into account habitat condition or management, which can cause variation in amounts of carbon stored. It is calculated for each 10m by 10m cell across the study area. Scores are scaled on a 0 to 100 scale, relative to values present within the mapped area. In all the ecosystem services maps that follow, the highest amounts (hotspots) are shown in red, with a gradient of colour to blue, which shows the lowest amounts (coldspots).
4.2.3 Results for the Nene Valley Carbon storage capacity is shown on Map 17. Away from peat soils (which are not present in the Nene Valley), woodlands provide the largest amount of carbon storage in the UK, with broadleaved woodlands typically storing the most. This is clear from the map, where broadleaved woodlands are shown in red, with coniferous woodland marked as orange. Thus the hotspots for carbon storage mirror the pattern of woodland cover in the Nene Valley, with highest values in the Rockingham Forest area in the north-east and in the Salcey Forest area to the south. Carbon storage values are relatively low in the NIA itself, reflecting the limited amount of woodland adjacent to the river. Water bodies, arable farmland and urban sealed surfaces provide the least capacity for carbon storage and are shown in dark blue on the map.
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Map 17:
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.3 Noise regulation capacity
4.3.1 What is it and why is it important? Noise regulation capacity is the capacity of the land to diffuse and absorb noise pollution. Noise can impact health, wellbeing, productivity and the natural environment and the World Health Organisation (WHO) have identified environmental noise as the second largest environmental health risk in Western Europe (after air pollution). It is estimated that the annual social cost of urban road noise in England is £7 to £10 billion (Defra 2013). Major roads, railways, airports and industrial areas can be sources of considerable noise, but use of vegetation can screen and reduce the effects on surrounding neighbourhoods. Complex vegetation cover such as woodland, trees and scrub is considered to be most effective, although any vegetation cover is more effective than artificial sealed surfaces, and the effectiveness of vegetation increases with width.
4.3.2 How is it measured? The EcoServ noise regulation model was used, with some modifications. First, the capacity of the natural environment is mapped by assigning a noise regulation score to vegetation types based on height, density, permeability and year round cover. Next, the noise absorption score in 30m and 100m radii around each point was modelled and the scores combined, which results in wider belts of vegetation receiving a higher score. The score was calculated for each 10 m by 10m cell across the study area, and is scaled on a 0 to 100 scale, relative to values present within the mapped area. High values (red) indicate areas that have the highest capacity to absorb noise pollution.
4.3.3 Results for the Nene Valley Noise regulation capacity is shown on Map 18. Given that woodland is by far the most effective habitat at absorbing noise pollution, it is not surprising that this map highlights the wooded areas in the Nene Valley, with large blocks of woodland receiving the highest scores (dark red on the map). The lowest scores (dark blue) are for sealed surfaces and water, which have no noise absorption capacity.
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Map 18:
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.4 Noise regulation demand
4.4.1 What is it and why is it important? Noise regulation demand estimates societal and environmental need for ecosystems that can absorb and reflect anthropogenic noise. Noise regulation demand combines an indicator showing the location of areas suffering from noise pollution, with two indicators showing societal need for noise abatement.
4.4.2 How is it measured? A model was developed based on the EcoServ noise regulation demand model, but with a number of modifications. Three indicators were developed and mapped for each 10m by 10m cell across the study area; one indicator that maps noise areas and two indicators of societal demand for noise abatement: Noise score – calculates the inverse log distance to different noise sources. The distances over which noise pollution occurs increases with increasing road traffic volume, and was matched to Defra noise models for the Nene Valley, with noise effects shown over the following distances: motorways = 1000m, dual carriageways = 500m, other A roads = 250m, railways = 300m Population score – maps societal need for noise regulation based on population density from 2011 UK census figures Health score – maps societal need for noise regulation based on Index of Multiple Deprivation health scores, with worse health indicating greater need. Each indicator was normalised from 0-1 and the scores combined, with noise score weighted 1 and societal demand scores combined with a weighting of 1 (0.5 for population score and 0.5 for health score). The final score was then projected on a 0 to 100 scale, as for the other ecosystem services. Note that this is an indicative map, showing areas that have generally high or low demand and is not a mathematical model. High values (red) indicate areas that have the highest demand for noise regulation.
4.4.3 Results for the Nene Valley Noise regulation demand is shown on Map 19. To better highlight the areas and distances over which there is demand for this service, the map only shows areas where there is a demand (scores from 1 to 100), with areas with zero demand shown as white. Demand is greatest in urban areas close to major roads, as these contain large populations, with potentially poor health scores, that would benefit from noise abatement from the main roads. The map also highlights the main road and rail networks, and especially the impact of the M1, A1(M) and A14, which are the most significant sources of environmental noise across the study area.
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Map 19:
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.5 Local climate regulation capacity
4.5.1 What is it and why is it important? Land use can have a significant effect on local temperatures. Urban areas tend to be warmer than surrounding rural land due to a process known as the “urban heat island effect”. This is caused by urban hard surfaces absorbing more heat, which is then released back into the environment, coupled with energy released by human activity such as lighting, heating, vehicles and industry. Climate change impacts are predicted to make the overheating of urban areas and urban buildings a major environmental, health and economic issue over the coming years. Natural vegetation, especially trees / woodland and rivers, are able to have a moderating effect on local climate, making nearby areas cooler in summer and warmer in winter. Local climate regulation capacity estimates the capacity of an ecosystem to cool the local environment and cause a reduction in urban heat maxima.
4.5.2 How is it measured? EcoServ was used to model local climate regulation capacity. The model calculates the proportion of the landscape that is covered by woodland / scrub and water features within a 200m radius around each 10m by 10m cell across the study area. However, temperature regulating effects of woodland and water will also occur in nearby adjacent areas, with the distance of the effect dependent on the patch size of the natural area. To incorporate this effect, a buffer was applied around each woodland / water patch, with wider buffers modelled around larger natural sites. Note that this model only includes woodland / scrub and water features. All greenspace is beneficial compared to artificial sealed surfaces, but there is no information available on the relative contribution of different types of natural surfaces to local climate regulation. I have therefore chosen to focus on the natural features with the most significant effects. The final capacity score was calculated for each 10 m by 10m cell across the study area, and was scaled on a 0 to 100 scale, relative to values present within the mapped area. High values (red) indicate areas that have the highest capacity to regulate temperatures, keeping them cool in the summer and warmer in the winter.
4.5.3 Results for the Nene Valley To better highlight the locations and distances over which this service is supplied, the local climate regulation capacity map (Map 20) only shows areas where there is supply of this service (scores from 1 to 100), with areas with zero capacity shown as white. As this model is based around woodland / scrub and water features, the map obviously highlights woodlands and river corridors, with larger patches and the adjacent benefitting areas receiving the highest scores (shown as red). Note that the Nene river corridor is effective at bringing local climate regulating services into the heart of the urban areas. Street trees are not included in the basemap, but would be a beneficial addition, as they can have a pronounced local effect on local climate in the urban core.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.6 Local climate regulation demand
4.6.1 What is it and why is it important? Local climate regulation demand estimates societal and environmental need for ecosystems that can regulate local temperatures and reduce the effects of the urban heat island. The urban heat island is only considered to be significant in larger urban centres, hence only urban areas greater than 1000 ha were modelled. Local climate regulation demand combines an indicator showing the location of areas suffering from the urban heat island effect, with two indicators showing societal need for local climate abatement.
4.6.2 How is it measured? Local climate regulation demand was mapped using an EcoServ model. Three indicators were developed and mapped for each 10m by 10m cell across the study area; one indicator that maps environmental need and two indicators of societal demand for local climate (temperature) regulation: Environmental need – maps the locations most prone to urban heating based on the proportion of sealed surfaces in urban areas greater than 1000 ha. Population density – maps societal need for local climate regulation based on population density from 2011 UK census figures Age risk – maps societal need for local climate regulation based on the proportion of the population in the highest risk age categories – defined as under 10 and over 65. Each indicator was normalised from 0-1 and the scores combined, with environmental need weighted 1 and societal demand scores combined with a weighting of 1 (0.5 for population density and 0.5 for age risk). The final score was then projected on a 0 to 100 scale, as for the other ecosystem services. High values (red) indicate areas that have the highest demand for local climate regulation.
4.6.3 Results for the Nene Valley The map of local climate regulation demand (Map 21) highlights the areas over which there is demand (scores from 1 to 100), with areas with zero demand shown as white. There are seven urban areas that are larger than 1000 ha and hence considered to have a demand for local climate regulation to counteract the effects of the urban heat island: Corby, Daventry, Kettering, Northampton, Peterborough, Rushden / Higham Ferrers, and Wellingborough. Within these urban areas, demand is generally greatest in the more densely built-up centres, with patterns of demand influenced by urban layout and the presence of parks, river corridors, and other greenspaces.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.7 Air purification capacity
4.7.1 What is it and why is it important? According to the World Health Organisation, air pollution is the greatest environmental health risk in Western Europe and globally. In the UK alone it is estimated to have an effect equivalent to 29,000 deaths each year and is expected to reduce the life expectancy of everyone in the UK by 6 months on average, at a cost of around £16 billion per year (Defra 2015). Air pollution also contributes to climate change, reduces crop yields, and damages biodiversity. Air purification capacity estimates the relative ability of vegetation to trap airborne pollutants or ameliorate air pollution. Vegetation can be effective at mitigating the effects of air pollution, primarily by intercepting airborne particulates (especially PM10) but also by absorbing ozone, SO2 and NOX. Trees are much more effective than grass or low-lying vegetation, although effectiveness varies depending on the species of plant. Coniferous trees are generally more effective than broadleaved trees due to the higher surface area of needles and because the needles are not shed during the winter.
4.7.2 How is it measured? Local climate regulation capacity was mapped using a modified version of the EcoServ model. The model assigns a score to each habitat type representing the relative capacity of each habitat to ameliorate air pollution. The cumulative score in a 20m and 100m radius around each 10m by 10m pixel was then calculated and combined. The benefits of pollution reduction by trees and greenspace may continue for a distance beyond the greenspace boundary itself, with evidence that green area density within 100m can have a significant effect on air quality. Therefore the model extends the effects of greenspace over the adjacent area, with the maximum distance of benefits set at 100m. Note that the model does not take into account seasonal differences or differences in effect due to prevailing wind direction. The final capacity score was calculated for each 10m by 10m cell across the study area, and was scaled on a 0 to 100 scale, relative to values present within the mapped area. High values (red) indicate areas that have the highest capacity to trap airborne pollutants and ameliorate air pollution.
4.7.3 Results for the Nene Valley The map of air purification capacity (Map 22) highlights areas of woodland, which are by far the best habitats at intercepting and absorbing air pollution, with the very highest scores from coniferous forests. Urban woodland is particularly effective as it has high capacity to absorb pollution and is also situated in locations likely to have high demand for the service (see next section). The lowest scores (dark blue) are from man-made sealed surfaces and water features which effectively have zero capacity to ameliorate air pollution. Similarly to local climate regulation capacity, street trees, which are not included in the basemap, would be a beneficial addition as they can be locally very important at absorbing air pollution adjacent to busy urban roads.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.8 Air purification demand
4.8.1 What is it and why is it important? Air purification demand estimates societal and environmental need for ecosystems that can absorb and ameliorate air pollution. Demand is assumed to be highest in areas where there are likely to be high air pollution levels and where there are lots of people who could benefit from the air purification service.
4.8.2 How is it measured? Air purification demand was mapped using a modified EcoServ model. Four indicators were developed and mapped for each 10m by 10m cell across the study area; two indicators that gave an approximate indication of air pollution levels (environmental need) and two indicators of societal demand for air purification: Distance to roads – maps a key source of air pollution by applying a log distance decay function to main roads, with a maximum distance set at 300m Sealed surface cover – maps % cover of sealed surfaces over 400m radius around each point as this has been shown to be correlated with pollution levels in scientific studies Population density – maps societal need for air purification based on population density from 2011 UK census figures in the adjacent area (300m radius around each point) Health score – maps societal need for air purification based on Index of Multiple Deprivation health scores in the adjacent area (300m radius), with worse health indicating greater need. The scores for each indicator were normalised and combined with equal weighting. The final score was then projected on a 0 to 100 scale, as for the other ecosystem services. High values (red) indicate areas that have the highest demand for air pollution amelioration.
4.8.3 Results for the Nene Valley Air purification demand (Map 23) is highest in the main urban centres as these have both higher air pollution levels and higher populations that would benefit from better air quality. The main road network is also clearly visible as a major pollution source, and where these main roads pass through built up areas, there is increased demand for air purification. By considering both the air purification capacity and demand maps, it is clear that planting (or maintaining) trees and woodland close to main roads and other pollution sources in built-up areas would be highly beneficial, with considerable cost savings to society possible.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.9 Water flow capacity
4.9.1 What is it and why is it important? Water flow capacity is the capacity of the land to slow water runoff and thereby potentially reduce flood risk downstream. Following a number of recent flooding events and the expectation that these will become more frequent over the coming years due to climate change, there is growing interest in working with natural process to reduce downstream flood risk. These projects aim to ‘slow the flow’ and retain water in the upper catchments for as long as possible. Maps of water flow capacity can be used to assess relative risk and help identify areas where land use can be changed. It can also form the first step in setting up a Payment for Ecosystem Services (PES) Scheme.
4.9.2 How is it measured? A bespoke model was developed, building on an existing EcoServ model and incorporating many of the features used in the Environment Agency’s catchment runoff models used to identify areas suitable for natural flood management. Runoff can generally be assessed based on three factors: land use, slope and soil type and so the following indicators were developed and mapped for each 10m by 10m cell across the Nene Valley and buffer area: Roughness score – Manning’s Roughness Coefficient provides a score for each land use type based on how much the land use will slow overland flow. Slope score – based on a detailed digital terrain model, slope was re-classified into a number of classes based on the British Land Capability Classification and others. Standard % runoff – was obtained from soil data and modified to reflect soil hydrological properties and their sensitivity to structural degradation from agricultural use. This was integrated with a layer showing impermeable areas where no soil was present (sealed surfaces, water and bare ground). Each indicator was normalised from 0-1, then added together and projected on a 0 to 100 scale, as for the other ecosystem services. Note that this is an indicative map, showing areas that have generally high or low capacity and is not a hydrological model. High values (red) indicate areas that have the highest capacity to slow water runoff.
4.9.3 Results for the Nene Valley Water flow capacity is shown on Map 24 (next page). The best areas for slowing water runoff are areas of woodland on flat land and permeable soils. The highest values occur over patches of highly permeable soil around Corby, Kettering and Peterborough, especially where woodland occurs over these soils. The main valley bottom of the Nene achieves quite high scores as these areas are flat and contain relatively permeable gravels. Given the lowland nature of the Nene Valley, slope is only a factor in a few locations. The worst areas (blue on the map) are areas of impermeable surface in urban areas, but note that patches of woodland in urban areas are highly beneficial and appear as red patches on the map. The map can be used to highlight opportunity areas that would be most suitable for natural flood management projects. These are likely to be areas that are relatively poor at the moment but by changing land use, the capacity could be enhanced.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.10 Water flow demand
4.10.1 What is it? This shows the relative demand for measures that reduce water runoff and is focussed around flood risk. Flooding can be caused by multiple sources, but the primary factors away from the coast are river (fluvial) and surface water or rainfall (pluvial) sources. Groundwater and reservoir sources can also cause flooding, but were not assessed here.
4.10.2 How is it measured? A map of flood risk was produced that combined the Environment Agency’s updated Flood Map for Surface Water (uFMfSW) with river flooding maps (Flood Zones 2 and 3). Maps that showed flood risk at greater than 1 in 100 and greater than 1 in 1000 risk were obtained for both surface water and river flooding and merged to show the relative combined risk from both sources. Note, however, that risks are not independent so could not be calculated mathematically; the maps merely show areas that are at risk of flooding from one or both sources and at which level. High values (red) indicate areas that have the highest demand for reductions in water runoff (i.e. highest potential flood risk). Note that this map does not include the impact of flood defences, so actual risk may be considerably lower. It would be possible to develop this indicator further in the future by including relative need of different land use types to be protected. For example, buildings require greater protection than other land uses, and naturally wet habitats require the least protection of all. The number of buildings and area at risk could also be assessed using the Environment Agency’s Communities@Risk dataset if that becomes available for the Nene catchment.
4.10.3 Results for the Nene Valley Map 25 shows water flow demand for the Nene Valley NIA and buffer zone. Unsurprisingly, flood risk is focussed adjacent to the river, within the NIA itself. But by zooming into the layer on GIS it’s possible to determine exactly which areas are at risk at a very fine scale. Many of the towns and villages in the Nene Valley have developed around the river, hence flood risk management is a significant and ongoing concern in the area.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.11 Water quality capacity
4.11.1 What is it and why is it important? Water quality capacity maps the risk of surface runoff water becoming contaminated with high pollutant and sediment loads before entering a watercourse, with a higher water quality capacity indicating that water is likely to be less contaminated. Agricultural and urban diffuse pollution are assessed.
4.11.2 How is it measured? A modified version of an EcoServ model was developed, which combines a coarse and fine-scale assessment of pollutant risk. At a coarse scale, catchment land use characteristics were used to determine the overall level of risk. The percentage cover of sealed surfaces and arable farmland in each sub-catchment was calculated and the values were re-classified into a number of risk classes. There is a strong link between the percentage cover of these land uses and pollution levels, with water quality particularly sensitive to the percentage of sealed surface in the catchment. At a fine scale, a modification of the Universal Soil Loss Equation (USLE) was used to determine the rate of soil loss for each cell. This is based on the following three factors: Distance to watercourse – using a least cost distance analysis, taking topography into account. Slope length – using a flow accumulation grid and equations from the scientific literature. Longer slopes lead to greater amounts of runoff. Land use erosion risk – certain land uses have a higher susceptibility to erosion and standard risk factors were applied from the literature. Bare soil is particularly prone to erosion. Each of the three fine scale indicators and the catchment-scale indicator were normalised from 0-1, then added together and projected on a 0 to 100 scale. As previously, this is an indicative map, showing areas that have generally high or low capacity and is not a process-based model. High values (red) indicate areas that have the greatest capacity to deliver high water quality. This model could be refined further, particularly in urban areas, which are not well catered for in the existing model.
4.11.3 Results for the Nene Valley Water quality capacity is shown in Map 26. The areas with greatest capacity to deliver high water quality are areas in the Rockingham Forest and rural areas to the west of the study area, which are sub-catchments with relatively low levels of urban and arable land-uses and are also not very close to water courses. Capacity can be variable across short distances as it is partly dependent upon slope and distance to water course, which change rapidly over short spaces. Arable farmland scores particularly badly at both a coarse and a fine scale of assessment and sub-catchments with a high proportion of arable farmland have the lowest scores (they are delivering the highest pollutant and sediment loads to watercourses). Urban areas are also relatively low scoring. Similarly to water flow capacity, it would be possible to use these maps to identify opportunity areas where land-use in currently low scoring locations could be altered to greatest effect to improve water quality.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.12 Water quality demand
4.12.1 What is it and why is it important? Water quality demand provides a map of the regulatory need for high water quality in each sub-catchment.
4.12.2 How is it measured? A very simple bespoke map was developed by dividing the area into the finest-scale sub-catchments used by the Environment Agency under the Water Framework Directive, and then determining the number of protected area designations in place in each sub-catchment. Protected areas designations were mapped for the following EU Directives:
Drinking Water Directive Fresh Water Fish Directive Habitats and Species Directive Nitrates Directive Urban Waste Water Directive All of these Directives are concerned with water quality to some degree and it is assumed that the greater the number of designations in place, the higher the demand for high water quality. Initially the Birds Directive was also included, but this was dropped following feedback, as there is no explicit water quality component to that Directive.
4.12.3 Results for the Nene Valley Water quality demand is shown on Map 27. Almost the whole of the Nene catchment is designated under at least one EU Directive, hence there is some demand for water quality throughout the area to Peterborough. There is high demand (with 3 or 4 designations) along the main river channel and immediate floodplain, with the very highest demand in the lower catchment, between Thrapston and Peterborough and on the adjacent Willow Brook.
Irthlingborough Lakes by John Abbott
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.13 Pollination capacity
4.13.1 What is it and why is it important? Insect pollinators are essential for human survival and for the natural environment. They pollinate 75% of the native plant species in Britain (Ollerton et al. 2011) and directly contribute an estimated £603 million per annum to the British economy through the pollination of agricultural crops (Vanbergen et al. 2014). They also pollinate orchard, allotment and garden fruit and vegetables and are essential to the continuing existence of most wild plant species. They have high cultural value, both in their own right and through the maintenance of our countryside and gardens. Pollination capacity measures the capacity of the land to provide pollination services by estimating the probability that wild insect pollinators will visit each particular pixel of land.
4.13.2 How is it measured? Pollination capacity was measured using an extension of an EcoServ model, which is itself based on pollination mapping work undertaken across Europe (Schulp et al. 2014). Pollination capacity was modelled in the following steps: 1. A map of all the hedgerows across the study area was compiled. Further details of the approach and the final hedgerow map is shown in Section 2.2.4 and Map 5. 2. A map of all potential pollinator nesting habitat was produced. This combined: Full habitats – all area under these habitats potentially provide pollinator habitat and includes semi-natural grasslands, scrub, gardens, and hedgerows. Edge habitats – only the edges of these habitat types are considered to provide suitable pollinator nesting habitats and includes all woodland types and parkland. For these habitats only the outer 10m was selected as habitat. 3. The next step was to calculate for each 10 m grid square the distance to the potential pollinator habitats identified above. 4. Finally, the visitation probability to each 10m grid square was calculated based on distance and using a formula given in Schulp et al. (2014). The end result was normalised and displayed on a 0-100 scale relative to values present within the study area. High values (red) indicate areas that have the highest probability of visits by insect pollinators.
4.13.3 Results for the Nene Valley Pollination capacity is shown in Map 28 and shows that the vast majority of the Nene Valley is potentially well served by pollinators. Indeed, although fields have become much larger over the last century, with the removal of many hedgerows, the hedgerow network is still extensive enough to leave few parts of the study area any great distance from potential pollinator habitat. In fact, almost every grid square in the Nene Valley has at least an 80% probability of visitation and the median probability of visitation is 97%. It’s also interesting to note that urban areas are particularly well served by pollinators (very high pollination capacity) due to the density of gardens. This is a finding backed up by recent scientific studies that have shown that pollinator diversity and abundance is usually higher in urban areas than in the surrounding countryside.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.14 Pollination demand
4.14.1 What is it and why is it important? Pollination demand assesses the relative need for insect pollination services by mapping the amount of pollinator dependent crops present in each grid square and weighting this by how dependent each crop type is on insect pollination. It assesses agricultural crops and orchard fruits, but does not include non- commercial produce grown in allotments or gardens as there is no reliable data available on the amount and type of produce grown in those locations. Hence this map will tend to underestimate pollination demand, especially in urban areas.
4.14.2 How is it measured? Demand for pollination was assessed using a bespoke model, in the following steps: 1. Data was obtained from Agcensus showing agricultural land use in 2Km by 2Km squares across the study area (this is taken from Defra’s annual June agricultural census). Orchards were identified from the MasterMap derived basemap. Pollinator dependent crops were identified as oilseed rape, field beans, linseed, and orchard fruits. 2. The area of pollinator dependent crops was determined from the above sources. 3. Pollinator dependency of each crop type was determined from the scientific literature. The mean pollinator dependency of orchard fruit was adjusted to the overall production value of different orchard fruits in the UK (Defra; no local data available). 4. Crop area was multiplied by dependency to give weighted % pollinator dependent crops. 5. The weighted % was projected in GIS and resampled at 1ha resolution 6. Values were then normalised on a 0 to 100 scale, relative to values present within the study area. High values (red) indicate areas that have the highest demand for insect pollinators.
4.14.3 Results for the Nene Valley If there were no insect pollinators, mean output of orchard fruits would fall by 80%, whereas output of oilseed rape and field beans would only fall by 25%. The much higher dependency of orchard fruits means that the demand from orchards is much higher than from the arable crops, and the orchard areas are highlighted as small red dots on the pollination demand map (Map 29). Arable crops are planted over much larger areas than orchards, with oilseed rape being by far the most commonly planted pollinator dependent crop. The large orange areas on Map 29, particularly to the north of Northampton and to the east of Thrapston in East Northamptonshire, highlight areas where oilseed rape is particularly prevalent. But note that although these arable crops create demand for pollination services over a much wider area, the level of demand (and resulting score) is much lower than that for the orchards. The urban areas have low demand for pollination services (shown as blue), but as previously stated, this does not take into account allotments and private gardens. The map has a ‘blocky’ appearance due to the coarse resolution of the agricultural data. A new data source has recently been released by CEH that maps crop type on a field by field basis, based on the new European Sentinel satellites. Using this data would greatly increase the spatial resolution of the pollination demand map, although the data is expensive to purchase.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.15 Agricultural production capacity
4.15.1 What is it and why is it important? Agricultural production models the capacity of the land to produce food under current farming practices. Farming is the dominant land-use within the Nene Valley and is also significant in terms of rural livelihoods and as a major contributor to the local economy. It is important that the impact on farming and rural livelihoods is taken into account when considering options and opportunities for land use change. It should be noted that agricultural production is reliant upon a combination of the natural environment and human inputs, in the form of machinery and other manufactured inputs, labour and expertise. Hence a value for agricultural production capacity includes more than simply natural capital and does not attempt to disentangle natural from human inputs.
4.15.2 How is it measured? A bespoke model was created that models the gross margin of agricultural production for each grid square. This involved a number of steps: 1. Crop areas and livestock numbers were obtained from agcensus, which is itself obtained from Defra’s June agricultural census. 2. Information on the financial performance of farm businesses in England was obtained from Defra’s Farm Business Survey. The average gross margin over the last five years (from 2010/11 to 2014/15) was calculated for each crop and livestock type. This takes into account yields (for crops) and farm gate prices, to give gross output, and subtracts typical variable costs (e.g. fertilizers, seeds, sprays, husbandry, feed and forage costs) to give gross margin. 3. For each crop and livestock type, the crop area and livestock numbers were multiplied by the relevant gross margin and summed to give the gross margin for each grid square. This was then divided by the area of farmland in each grid square to give the total gross margin per hectare of farmland. 4. The data were imported into GIS and projected onto the agricultural areas of the basemap, resampled at a 1 ha resolution and normalised on a 0 to 100 scale relative to values present within the study area. Note that this does not take into account fixed costs such as buildings and machinery. However, gross margin is the usual way in which agricultural outputs are reported in government statistics and in the scientific literature.
4.15.3 Results for the Nene Valley The map showing agricultural production capacity is shown on the next page (Map 30). The very highest scores occur on the high grade agricultural land to the east of Peterborough. Relatively high agricultural production is also apparent in many parts of the study area, especially towards the south and east, and also around Kettering and Wellingborough. These are areas dominated by cereal farming, principally wheat and oilseed rape. Dairy, beef and sheep farming is also present in the study area, but more frequent in the west. There is obviously no agricultural production from non-farmed areas such as urban areas, woodland and water, and these are shown in blue on the map.
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Map 30: Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.16 Tranquillity capacity
4.16.1 What is it and why is it important? According to the Campaign to Protect Rural England (CPRE) tranquillity is “a quality of calm that people experience in places full of the sights and sounds of nature”. It is generally associated with the countryside and can be impacted “by the intrusive sights and sounds of man-made structures”. Tranquillity is considered to be an important cultural service delivered by the natural environment and access to tranquil places has been linked with enhanced health and wellbeing. Furthermore, tranquillity is one of the most stated reasons for visiting the countryside in general.
4.16.2 How is it measured? CPRE and Natural England commissioned a major study into tranquillity in the 2000s, involving an extensive public consultation to discover the components that contributed to an experience of tranquillity. Positive factors included the openness of the landscape, perceived naturalness of the landscape, presence of rivers, and areas of low noise, whilst negative indicators included presence of other people, visibility of roads and urban development, general signs of overt human impact, and road, train and urban area noise. Following this consultation a composite indicator was developed based on 44 positive and negative factors that contribute towards tranquillity and this was turned into a national map. The National Tranquillity Mapping Data 2007 was obtained under licence from CPRE. The original data was resampled at 10m by 10m resolution and normalised across the study area on a 0 to 100 scale relative to values present within the study area.
4.16.3 Results for the Nene Valley The highest areas of tranquillity (in red) are around the Rockingham Forest area and along the south- eastern edge of the study area (see Map 31), which correspond to the areas with least population. The NIA itself and river corridor offer variable levels of tranquillity as several major towns overlap with this area, which inevitably reduces tranquillity. However, it is noticeable, particularly in Peterborough, that the river corridor provides an area of tranquillity that extends right into the heart of the city. Unsurprisingly, the least tranquil areas are in and around the towns.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.17 Accessible nature capacity
4.17.1 What is it and why is it important? Access to greenspace is being increasingly recognised for the multiple benefits that it can provide to people. In particular there is strong evidence linking access to greenspace to a variety of health and wellbeing measures. Research has also shown that there is a link between wellbeing and perceptions of biodiversity and naturalness. Natural England and others have published guidelines that promote the enhancement of access, naturalness and connectivity of greenspaces (e.g. Natural England 2010). The two key components of accessible nature capacity are therefore public access and perceived naturalness. Both of these components are captured in the model, which maps the availability of natural areas and scores them by their perceived level of naturalness.
4.17.2 How is it measured? An EcoServ model was used to map accessible nature capacity. In the first step, accessible areas are mapped. These are defined as: Areas 10m either side of linear routes such as Public Rights of Way, pavements and Sustrans routes. Publicly accessible areas such as country parks, CRoW access land, local nature reserves and accessible woodlands. Areas of green infrastructure marked as accessible, including parks, playgrounds, and other amenity greenspaces. These areas were then scored for their perceived level of naturalness, with scores taken from the scientific literature. Naturalness was scored in a 300m radius around each point, representing the visitors experience within a short walk of each point. The resulting map shows accessible areas, with high values representing areas where habitats have a higher perceived naturalness score. Scores are on a 1 to 100 scale, relative to values present within the study area. White space shows built areas or areas with no public access. Larger continuous blocks of more natural habitat types will have higher scores than smaller isolated sites of the same habitat type. One consequence is that linear routes, such as footpaths, that pass through land with no other access do not usually score highly. It would be possible to adjust the score so that it provided a score simply for the habitat that the path passes through, rather than a 300m focal distance around the path, most of which is inaccessible, if that was considered preferable.
4.17.3 Results for the Nene Valley Accessible nature capacity is shown in Map 32. The larger areas of publicly accessible natural greenspaces are clearly visible in red, including various woodlands in the Rockingham and Salcey Forests, Nene Park, Pitsford Water, Stanwick Lakes and Irthlingborough Lakes and Meadows. Urban greenspaces generally score a little lower as these often do not score highly for naturalness. There is an extensive network of paths and linear routes throughout the Nene Valley, which can be clearly identified from the map, although these are all low scoring due to the use of 300m focal buffers around each point (see paragraph above).
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.18 Accessible nature demand
4.18.1 What is it and why is it important? This indicates where there is greatest demand for accessible nature, which is strongly related to where people live. Research, including large surveys such as the Monitor of Engagement with the Natural Environment (MENE), has shown that there is greatest demand for accessible greenspace close to people’s homes, especially for sites within walking distance. Furthermore, Natural England have published Accessible Natural Greenspace Standards (ANGSt), which set out guidelines on the size and proximity of greenspace in relation to where people live (Natural England 2010). As part of the wider Nene Valley NIA project, a visitor access study was performed within multiple locations in the Upper Nene Valley Gravel Pits SPA (Liley et al. 2014). This provided data on the distance that people travelled to visit the SPA and mode of transport and confirmed that the vast majority of visits were of local origin.
4.18.2 How is it measured? There are two types of demand map that can be produced for accessible nature; demand based on trip sources (homes) and demand based on destination areas (sites), which provide slightly different information. I have produced both types of model here, by modifying a model in the EcoServ toolkit. Trip sources model - this model maps demand, taking no account of habitat, based on three indicators: Population density – based on 2011 census data, as the larger the population the greater demand for accessible nature. Health scores – taken from the Index of Multiple Deprivation general health scores, with the assumption that those in worse health have the greatest need and would benefit most from access to greenspace. Distance to footpaths and access points – maps all pavements, Public Rights of Way, Sustrans routes and other paths and combines with public transport stops and access points to parks / country parks, and calculates distance from these. The three indicators are calculated at three different scales as demand is strongly related to distance. The Visitor Access Study of the Upper Nene Valley Gravel Pits SPA (Liley et al. 2014) was used to determine appropriate distances. The distances chosen (and rationale) were: 800m (the median distance travelled by people walking to sites), 3.2 Km (median distance travelled by all visitors using all modes of transport), and 14 Km (90% of all visitors travelled less than this distance). The three indicators were normalised from 0-1, then combined with equal weighting at each scale and then the three different scales of analysis were combined, also with equal weighting and projected on a 0 to 100 scale. High values (red) indicate areas (sources) that generate the greatest demand for accessible nature. Sites (ANGSt) model – this model examines demand focussed around existing natural greenspaces and uses Natural England’s ANGSt guidelines (Natural England 2010) to define sites and distances. First, sites are selected that contain accessible natural greenspace, using ANGSt definitions of natural greenspace (this excludes formal recreation areas, allotments and cemeteries). Next, the same model as above is run with the three indicators of population density, health scores, and distance to footpaths and access points. However, this is now focussed on the accessible natural greenspace that has been identified, and an area threshold is now applied at the three different scales so that only sites above a certain
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Mapping Natural Capital and Ecosystem Services in the Nene Valley threshold were considered at each scale. The thresholds and scales were adjusted to match ANGSt guidelines (Natural England 2010), as follows: Demand for sites with a minimum size of 2 ha were considered over a distance of 300m Demand for sites with a minimum size of 20 ha were considered over 2Km Demand for sites with a minimum size of 100 ha were considered over 5Km The indicators were combined in the same way as before. This time, high values indicate sites that receive the highest demand.
Note that both of these models map local demand and do not take into account demand from people living outside of the study area, although as recorded from the visitor survey, there are likely to be very few people visiting from far afield.
4.18.3 Results for the Nene Valley Demand for accessible nature based on trip sources is shown on Map 33. It is strongly focussed around the urban areas in the study area, especially Northampton, Peterborough and Corby and highlights the importance of urban areas in driving demand for accessible nature. There is still some demand throughout the study area, although local demand will be lower in areas that are further away from population centres. As already stated, however, the model does not take into account the higher levels of demand generated by specific popular sites, but this map does give an indication of the likely demand if new sites were to be created. Map 34, on the other hand, shows the demand at existing areas of accessible greenspace. Again it highlights the demand generated by the large urban centres, with sites in Peterborough, Northampton and Corby receiving the highest demand. It also illustrates the importance of site size, as small sites face lower demand than large sites. This map does not take into account site quality, or the draw that honeypot sites will generate, but does highlight the strong local demand generated by urban centres.
Winter morning by John Abbott
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.19 Green travel capacity
4.19.1 What is it and why is it important? Green travel routes are linear travel networks that pass through natural areas, and green travel capacity maps the availability of such networks. Availability of such routes is associated with multiple benefits including increasing physical exercise, reducing pollution and congestion, and general health and wellbeing benefits.
4.19.2 How is it measured? An EcoServ model was used to map green travel capacity. The method has some similarities to the accessible nature capacity model as the first step identifies travel routes and the second step assesses their naturalness. Travel routes were identified from Sustrans cycle routes, Public Rights of Way / Core paths and all pavements and paths. Small areas of isolated paths were excluded. The perceived naturalness of the habitat through which the travel route passes was then determined. Scores are on a 1 to 100 scale, relative to values present within the study area.
4.19.3 Results for the Nene Valley Green travel capacity is shown on Map 35. The map highlights the travel network of paths, pavements and cycle routes that spreads throughout the Nene Valley. Many of the highest scores (red coloured routes) occur in the heart of the NIA, where routes travel close to the river and through adjacent natural habitats.
Cycling in Nene Park by Chris Porsz
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 4.20 Green travel demand
4.20.1 What is it and why is it important? This model estimates the societal demand for green travel routes, based on the location of popular travel destinations. It is focussed more around frequent regular travel such as commuting to school and work, rather than infrequent leisure journeys.
4.20.2 How is it measured? I carried out modifications to an EcoServ model to map green travel demand. Initially, potential travel destinations were mapped, which were taken to be town and village centres, railway stations, schools and colleges. These points were buffered and connected to the travel network identified in the green travel capacity model. Travel along the network was then modelled using a least-cost analysis, based on distance, up to a maximum distance of 10 Km. Scores are on a 1 to 100 scale, relative to values present within the study area.
4.20.3 Results for the Nene Valley Travel destinations are shown as black circles on Map 22. These are clustered in the towns and hence the greatest demand is very much centred on and immediately around these urban areas. However, there is still strong demand for green travel routes close to and between these urban areas. There is also at least some demand mapped for green travel routes along much of the river corridor, highlighting the role that green infrastructure plays in connecting places. Note that all of the travel destinations used in this study were urban destinations. It would be interesting to add the key visitor locations within the rural Nene Valley and then to repeat the analysis.
Autumn on the river by Carol MacIntyre-Jones Natural Capital Solutions Ltd 74
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 5. Delivering multiple ecosystem services
5.1 Overall supply of ecosystem services The average (mean) provision across ten ecosystem services modelled in this project is shown in Map 37. The ecosystem services are the capacity to supply carbon storage, noise regulation, local climate regulation, air purification, water flow, water quality, pollination, food production, tranquillity, and accessible nature. Green travel capacity was not included in this average map as it is measured in a similar way to accessible nature capacity and so was excluded to avoid double counting. The map highlights the importance of woodlands in delivering multiple ecosystem services, with the Rockingham Forest and Salcey Forest areas delivering the greatest amounts of high-scoring patches. The River Nene corridor is also distinguishable as supplying medium to high levels of ecosystem services throughout its length. The river corridor is also effective at bringing habitats delivering high levels of ecosystem services right into the heart of urban areas, and this is particularly prominent in Peterborough, Northampton and Kettering. The river corridor is acting as an effective green (and blue) corridor, providing continuous habitats that deliver moderate to high levels of ecosystem services throughout much of its course. The woodlands on the other hand tend to be more isolated, delivering very high levels of ecosystem services, but surrounded by habitats that are less good at delivering multiple benefits. Farmland is less multi-functional, with the dominant service being that of agricultural production, but is still able to deliver moderate levels of ES overall, particularly through services such as tranquillity. The areas delivering the lowest levels of ecosystem service provision are, unsurprisingly, the urban areas, but in these areas, parks and greenspaces (especially urban woodlands) can be seen to be really important in delivering multiple benefits.
5.2 Hotspots of ES supply The capacity to which the Nene Valley is able to provide hotspots of multiple ecosystem services is shown in Map 38. Here each polygon can supply between 1 and 11 ecosystem services. A hotspot is defined as the top 20% of the area of the Nene Valley that has the highest provision of ecosystem services across the ten ecosystem services included above, or the presence of a key location for habitat for biodiversity (taken from Map 4). The hotspots map paints a similar picture to the average supply map (Map 37), except that the trends are now more exaggerated. The woodland areas are now highly prominent, providing hotspots of delivery for multiple ecosystem services (typically 7 or more), whilst much of the rural farmland is providing zero or one hotpot only (usually for agricultural production). But note that the blue areas do not indicate that there is no service provision, only that they are not areas where service provision is high. The River Nene corridor generally provides hotpots for a moderate and in certain places high number of services. In total 3.5% of the area of the NIA plus 3Km buffer is a hotspot for the supply of 7 or more ecosystem services, whilst 24.9% is not a hotspot for any services. The mean number of hotspots delivered by each pixel of land is 1.7.
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5.3 Overall demand for ecosystem services
The average (mean) demand for seven ecosystem services modelled in this project is shown in Map 39. These are demand for noise regulation, local climate regulation, air purification, water flow, water quality, pollination, and accessible nature. Again green travel capacity was not included in this average map as it is not really comparable to the other maps. The average demand map clearly highlights the importance of the urban areas in driving demand, with the very highest demand from part of Northampton and Peterborough. In urban areas the overall score is driven by strong demand for noise regulation, local climate regulation, air purification, and accessible nature, and in urban areas that are in the floodplain of the River Nene there is some additional demand for water flow and water quality services. The Nene river corridor, especially in the lower reaches, has moderate demand overall, driven primarily by high demand for water flow and water quality services. The lowest demand areas overall are generally in the middle of the countryside and away from the river corridor.
5.4 Hotspots of ES demand The hotspots of ecosystem services demand in the Nene Valley are shown in Map 40. The value shown relates to the number of different ES for which that grid square is a hotspot (out of a maximum possible of 7). A hotspot is defined as the top 20% of the total study area that has the highest demand for each of the seven individual ecosystem services included above. The hotspots map is very similar to the average demand map (Map 39). Urban areas are the clear hotpots of demand, with the majority of urban areas being hotpots for between 3 and 5 ecosystem services. The main road network and the river floodplain in its lower reaches are demand hotpots for 2-3 ecosystem services in general, whilst large areas of the rural countryside away from the rivers are not hotpots of demand for any service. In total 15.8% of the area of the NIA plus 3Km buffer is a hotspot of demand for 3 or more ecosystem services, whilst 38.8% is not a hotpot for any services.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6. Monetary valuation
6.1 Introduction There is a great deal of interest in providing a monetary valuation of ecosystem services and is an area being actively pursued by government, researchers and practitioners. Monetary valuation of ecosystem services has a number of key advantages: it provides a single unit for comparing options, it can be used directly in cost-benefit analysis, politicians and business people like it, and benefits not put in monetary terms are often ignored. However, it should be borne in mind that some ecosystem services remain very hard to value in this way. Hence any valuation will only provide a monetary value for a small number of ecosystem services. The overall value shown in any valuation is therefore likely to be an underestimate of the true value of the natural environment, but it does give a good indication of its importance for services that are often largely ignored in decision making. Gaining a spatial perspective on the variation in values across a study area such as the Nene Valley using maps, provides much additional insight. Biophysical and socio-economic conditions vary greatly across space, as has already been seen for the previous maps, and are likely to lead to significant spatial differences in the value of ecosystem services. There is little knowledge about how ecosystem values differ across space and their spatial determinants and this work is at the cutting edge of ecosystem services research. Potential applications of such an approach include assessing risks, impacts and opportunities, comparing options, land-use planning, awareness raising, and ecosystem (natural capital) accounting. In all cases maps can greatly enhance communication and visualisations, and enable values to be seen across any scale or site of interest across the study area. In the work presented here I have carried out a monetary valuation of four ecosystem services, where there is enough information to enable a value to be calculated. This is for: 1.) Agricultural and orchard production 2.) Greenhouse gas balance, taking into account emissions from agriculture and carbon sequestration 3.) Pollination 4.) Expenditure on recreation Below I outline the methods, provide a summary of the results and raise some key discussion points, including a sensitivity analysis, for each ecosystem service. I end by bringing it all together to show the overall value of the ecosystem services provided by the Nene Valley and its Nature Improvement Area. The work presented here updates initial valuation work presented in a document published on the Nene Valley NIA website in 2015 entitled “Valuation of ecosystem services in the Nene Valley Nature Improvement Area”.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6.2 Agricultural and orchard production
6.2.1 Introduction The value of agricultural and orchard production has been mapped based on gross margin, which is defined as gross output minus variable costs. This is the most common approach used in ecosystem services studies and government statistics. Note that agricultural and orchard production relies on a combination of natural capital and other types of capital including manufactured capital in the form of machinery and other inputs, and human capital in the form of labour and expertise. It is impossible to properly disentangle the relative contribution of these different types of capital and no attempt has been made to do so here. Some previous studies have calculated the ‘resource rent’ for agriculture, which is defined as the value of agricultural production after all human-related inputs have been subtracted. However, this approach is controversial and often results in values that are negative or very small. In addition, the main aim of the current work was to indicate the monetary flows derived from the study area, rather than providing a strict set of environmental-economic accounts, where the key aim would be to account for natural capital separately from other forms of capital.
6.2.2 Methods Agricultural production The value of agricultural production was mapped in the following steps: 1. Crop areas and livestock numbers were obtained from agcensus, which is itself obtained from Defra’s June agricultural census, for each 2Km by 2Km grid square in the study area. 2. Information on the financial performance of farm businesses in England was obtained from Defra’s Farm Business Survey. The average gross margin over the last five years (from 2010/11 to 2014/15) was calculated for each crop and livestock type. This takes into account yields (for crops) and farm gate prices, to give gross output, and subtracts typical variable costs (e.g. fertilizers, seeds, sprays, husbandry, feed and forage costs) to give gross margin. Note that this does not take into account fixed costs such as buildings and machinery. 3. For each crop and livestock type, the crop area and livestock numbers were multiplied by the relevant gross margin and summed to give the gross margin for each grid square. This was then divided by the area of farmland in each grid square to give the total gross margin per hectare of farmland. 4. The data were imported into GIS and projected onto the agricultural areas of the basemap and resampled at a 1 ha resolution. The final map provides values as £ per hectare. Note that this is the same map as shown in Section 4.15, except that the map is shown in monetary terms (£ per hectare) rather than being projected on a 0-100 scale relative to other values in the study area.
Orchard production The value of orchard production was also estimated based on gross margin for each grid square. Data on orchards is incomplete in agricultural statistics, so orchards were identified from the basemap, which was itself based on MasterMap. The area of orchards was multiplied by the average gross margin for top (orchard) fruit over the last five years, taken from the Farm Business Survey. This takes into account variable costs but not fixed costs. The data was converted into a raster and aggregated at 1 ha resolution to match the agricultural production map.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6.2.3 Results for the Nene Valley The value of agricultural production across the Nene Valley is shown on Map 41, whilst the value of orchard production is shown on Map 42. The total annual value across the Nene Valley NIA and the wider study area is shown in Table 5.
Table 5: Total annual value of agricultural and orchard production across the study area
Service Nene Valley NIA Nene Valley NIA plus 3 Km buffer Agricultural production (£) 16,505,237 74,723,192 Orchard production (£) 432,895 1,200,261
The mean annual value of agricultural production (gross margin) across the Nene Valley and averaged over the 5-year period is £604 per hectare if areas where agriculture is not present are excluded, or £440 across the whole area. Higher than average production is generally found towards the south and east of the study area, which is dominated by cereal and oilseed rape cropping, with lower than average values to the north and west. Orchards only make up 0.1% of the land area of the wider NIA plus buffer, hence orchard production value is zero for most of the study area (shown as blue on Map 42). The largest patch of orchards is around Corby with other small patches spread fairly evenly throughout the area. The overall value is therefore much lower than for agricultural production, with a mean value of £7 per hectare when summed across the whole study area. However, the value per hectare of orchard is considerably higher, at over £7500 per hectare.
6.2.4 Discussion and sensitivity analysis Agricultural and orchard production values are based on market prices and are therefore relatively robust to assumptions and methodological considerations. Production values will still vary as commodity and input prices fluctuate, although these effects are dampened by considering gross margin. To examine the potential impact of this I looked at the maximum and minimum gross margins recorded in the Farm Business Survey over the last five years. Winter wheat and winter oilseed rape are the dominant crops in the area and comprise approximately 80% of the value of arable crops. Over the last 5 years winter wheat gross margin varied between £699 and £993 (84 to 112% of the mean value), with winter oilseed rape varying from £510-1080 (69-146% of the mean). Livestock gross margins also fluctuated by similar amounts with the gross margin for dairy cows fluctuating by only 87-115% of the mean, but finished suckler cattle varying by the most (47-139% of the mean).
Assessing all crops and livestock together, gross margins generally fluctuated by around 75 to 125% of the five-year mean, hence the agricultural production values mapped here are subject to that same level of variability. This would result in the overall agricultural production value ranging from £12.4-20.6M per annum for the NIA over the last five years, or from £56.0-93.4M for the full study area. Note however, that larger fluctuations do occur and commodity prices have been known to double from one season to the next, hence greater variability is possible. If gross margins vary differentially for different crops and livestock it is likely to lead to different patterns of cropping in subsequent seasons or a move away from one type of farming system, as has been seen by the fluctuating fortunes of dairy farmers in the UK in
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Mapping Natural Capital and Ecosystem Services in the Nene Valley recent years. This would then have an effect of the production value and other ecosystem services produced across the study area.
In contrast to agricultural production, orchard gross margin has been remarkably constant over the last five years according to the Farm Business Survey. Gross margin has varied within a range from 94 to 105% of the mean value, hence the overall production value of orchards in the Nene are likely to have remained fairly constant over recent years. Therefore orchard production value will have ranged from approximately £407,000-455,000 per annum for the NIA over the last five years, and from £1.13-1.26M for the full study area.
Hay bales in the Nene Valley by Martin Rogers
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6.3 Greenhouse gas balance
6.3.1 Introduction Plants can absorb carbon dioxide from the atmosphere, but different types of vegetation and different land-uses are able to store and sequester very different amounts. In addition, agricultural activities release
CO2 and other greenhouse gasses such as methane and NO2 into the atmosphere, with emissions highly variable depending upon the type of farming practices employed. Here I examine: A. Carbon sequestration – the amount of carbon that can be captured from the atmosphere over a calendar year. B. Agricultural emissions – the amount of greenhouse gas emissions per hectare from agricultural activities. C. Overall greenhouse gas balance – the amount of carbon sequestration minus agricultural emissions for each grid square. The greenhouse gas balance reported here represents the agriculture and land use, land use change and forestry (LULUCF) sectors for which national emissions information is collected. For the UK as a whole agricultural emissions were 49 M tonnes CO2 equivalent in 2015, whereas LULUCF was a net carbon sink, sequestering 9 MtCO2e (Committee on Climate Change 2016).
6.3.2 Methods – physical flow accounts Carbon sequestration Carbon is sequestered (captured) by growing plants. Plants that are harvested annually (e.g. arable crops, improved grassland) will be approximately carbon neutral over the course of a year as the sequestered carbon is immediately harvested. There is very little information about sequestration in other habitats (apart from woodland), but these are likely to be very low and no peat bogs are present in the Nene that would also sequester significant amounts. Therefore, estimates are solely based on woodland carbon sequestration in the following steps: 1. Woodland habitat was identified from the base map and classified as either broadleaved, coniferous or mixed woodland. 2. The most up-to-date species mix available for the East Midlands was obtained from the National Forest Inventory Report (Forestry Commission 2011). This shows the overall proportion of species: Broadleaves: Oak 17.4%, Ash 12.8%, Sycamore 9.8%, Hawthorn 8.8%, Birch 7.5%, Hazel 3.6%, Willow 2.4%, Beech 1.4%, Sweet chestnut 1.3%, Alder 0.7%, and other broadleaves 15.0%. Conifers: Scots pine 6.9%, Corsican pine 6.5%, Norway spruce 2.0%, Larches 1.9%, Douglas fir 0.5%, Lodgepole pine 0.4%, Sitka spruce 0.2%, and other conifers 0.6%. 3. Age structure, management and typical age at harvesting: Broadleaves – only some in plantations, often harvested older than conifers and significant amount of stock in area is >60 years old (Forestry Commission 2002). Conifers – mostly in plantations, plantation stock typically harvested between 35 and 60 years and very little stock in Northamptonshire predates 1950s. 4. Used the Woodland Carbon Code Carbon Lookup Tables (Woodland Carbon Code 2012a) to estimate average carbon sequestration rates per year for UK woodland. Assumed average yield class and spacing, but no ongoing forest management. Broadleaves: used mean annual sequestration rate over 100 years, for oak, beech, and SAB (sycamore, ash, birch), and followed Lookup Table Guidelines (Woodland Carbon Code 2012b) Natural Capital Solutions Ltd 88
Mapping Natural Capital and Ecosystem Services in the Nene Valley for the most appropriate model to use for the remaining species, with mean adjusted to ratio of species mix in the East Midlands. Conifers: used mean annual sequestration rate over 60 years for all conifer species listed above, with mean adjusted to ratio of species mix in the East Midlands (as above). 5. The area of broadleaved, coniferous and mixed woodland in each grid square was multiplied by the
appropriate mean annual sequestration rate to give the total tonnes of CO2 sequestered annually per hectare. This was mapped in GIS.
Agricultural emissions
I followed Bateman et al. (2013) to estimate the greenhouse gas emissions (in CO2 equivalents) per hectare from agricultural activities. Three types of agricultural emissions were assessed: 1. Emissions from typical farming practices (e.g. tillage, sowing, spraying, harvesting, and the production, storage and transportation of fertilizers and pesticides) for each major crop type was calculated by multiplying the emissions figures in Bateman et al. (2013) by the area of each crop type in each grid square. The area of crop type was taken from the agcensus data described earlier.
2. Emissions of N2O from fertilizers was calculated by multiplying the emissions figures in Bateman et al. (2013) by the area of each crop type in each grid square.
3. Emissions of N2O and methane from livestock, caused by enteric fermentation and the production of manure, were calculated by multiplying the emissions per head of dairy cows, beef cattle and sheep (Bateman et al. 2013), by the livestock numbers in each grid square (from agcensus). Total emissions were summed for each grid square and projected onto the agricultural areas on the basemap in GIS.
Overall greenhouse gas balance Overall greenhouse gas balance was simply calculated in GIS as sequestration minus emissions for each grid square, with negative values indicating net emissions and positive values indicating net sequestration.
6.3.3 Results for the Nene Valley – physical flow accounts The average annual carbon sequestration rate for broadleaved and coniferous woodlands in Northamptonshire is shown in Table 6.
Table 6: Average annual carbon sequestration rate for woodlands in Northamptonshire Woodland type Sequestration rate
tCO2e/ha/yr Broadleaved 9.37 Coniferous 12.13
Emissions from arable farming are typically around 1.5 tCO2e/ha/year, with some variation depending on the crop type. Emissions associated with livestock farming are considerably higher, due primarily to the release of methane through enteric fermentation. Emissions per hectare depend on the stocking density and livestock type, but dairy is the highest at around 2.5 tCO2e per year per head, with additional emissions from agricultural activities and fertilizer applications to grasslands, which are higher than from arable crops in the case of temporary leys.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley Agricultural emissions per hectare are on average lower than the rate of sequestration per hectare in woodlands. However, as there is far more agricultural land than woodland across the study area, the Nene catchment is a net emitter of CO2, with an average emission of 0.56 tCO2e per hectare per year. Overall annual rates of carbon sequestration, agricultural emissions and greenhouse gas balance are shown in Table 7.
Table 7: Total physical flow of carbon sequestration, agricultural emissions and greenhouse gas balance across the study area.
Annual total Nene Valley NIA Nene Valley NIA plus 3 Km buffer Carbon sequestration (tCO2e) 16,783 115,397
Agricultural emissions (tCO2e) -48,503 -210,417 Greenhouse gas balance (tCO2e) -31,720 -95,020 NB. Negative values (in red) indicate emissions, positive values indicate sequestration.
6.3.4 Valuation Providing a monetary valuation of greenhouse gas emissions and sequestration relies on choosing an appropriate price for carbon. There are a wide range of prices available from different sources, varying by more than an order of magnitude and these are summarised in Table 8 and described briefly below:
Table 8: Carbon prices from different sources Valuation £ price per
tonne of CO2 EU Emissions Trading Scheme current price – October 2016 5.18 UK current floor price 2015-16 (Ares 2014) 18.08 UK government target carbon price by 2020 (Ares 2014) 30.00 Woodland carbon unit (Woodland Carbon Code 2014) 4.90 Appropriate carbon price (Dietz & Stern 2014) (range £21-67) 44.00 Social cost of carbon meta-analysis (Tol 2012) 36.00 UK Government (DECC 2015a) - traded price 2015 6.00 UK Government (DECC 2015b) - non-traded price 2015 62.00
The EU Emissions Trading Scheme is the largest carbon market in the world, but over the last few years
prices have ranged from a few pence to above £30 per tonne of CO2. It’s currently (October 2016) trading at around £5.18 per tonne. The UK government now insists on a minimum (floor) price for carbon of £18.08 and there is a target for the carbon price to have risen to £30 by 2020 (Ares 2014). The global average price for carbon sequestered through woodland planting schemes was reported to be around $6.00 (£4.90 by October 2016 currency rates) in 2014 (Woodland Carbon Code 2014). According to a recent analysis by Dietz and Stern (2014) carbon should be priced at anything from £21- 67 presently and should rise rapidly over the next few years. A meta-analysis of 47 studies (yielding 232 estimates) based on the social cost of carbon gave a mean estimate of €49 per tonne (c. £44 by October 2016 currency rates) (Tol 2012).
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Mapping Natural Capital and Ecosystem Services in the Nene Valley The official government advice for performing assessments and appraisals of greenhouse gasses using the Green Book (DECC 2015a) provides a current price for traded carbon (£6) and a separate price for non-traded carbon (£62) at very different levels (DECC 2015b). This is based on the cost of mitigating carbon emissions. These prices are predicted to align over the coming few years at the level of the higher non-traded price.
The UK Government non-traded carbon price was selected for use in this study. Using the woodland carbon unit price was considered as this would reflect the exchange value that would be received if such a scheme was set up in the Nene Valley. However, this price reflects the current institutional setup of carbon markets rather than the true value of carbon sequestration (eftec 2015). The non-traded carbon price, on the other hand, is calculated based on marginal abatement costs and reflects the costs of achieving politically motivated carbon reduction targets. Furthermore, there is a growing consensus amongst academics, government and practitioners to use this price (e.g. Bateman et al. 2013, Khan et al. 2014, eftec 2015).
6.3.5 Results for the Nene Valley – valuation and spatial patterns Carbon sequestration value across the Nene Valley is shown in Map 43. This clearly highlights all areas of woodland as well as trees outside of woodlands and the values that these provide. The value of woodland carbon sequestration is broadly comparable to that of agricultural production, at £581 per hectare per year for broadleaved woodland and £752 for coniferous woodland. The overall value of carbon sequestration across the whole study area is £7.15M per annum (Table 9), which amounts to approximately £42 per hectare. The pattern of agricultural emissions across the Nene (Map 44) reveals that emissions are greatest in the western parts of the study area, where more livestock farming occurs. Emissions occur from the vast majority of the study area, with the exception of urban areas and larger woodland blocks. The overall cost of agricultural emissions is shown in Table 9 and amounts to £13.0M per annum across the whole study area, or £77 per hectare per year. Overall greenhouse gas balance has been calculated from the previous two maps and clearly reveals area of net emissions and those with net sequestration (Map 45). The west and north-west parts of the study area have the greatest overall emissions, whereas the north-eastern part of the Nene Valley around Rockingham
Forest has the greatest amount of sequestration. Overall the Nene catchment is a net emitter of CO2, with overall costs of £5.89M per annum over the NIA plus buffer, which is an average of £35 per hectare per year.
Table 9: Total value of carbon sequestration, agricultural emissions and greenhouse gas balance across the study area.
Annual total Nene Valley NIA Nene Valley NIA plus 3 Km buffer Carbon sequestration (£) 1,040,555 7,154,588 Agricultural emissions (£) -3,007,187 -13,045,846 Greenhouse gas balance (£) -1,966,632 -5,891,258 NB. Negative values (in red) indicate emissions, positive values indicate sequestration.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6.3.6 Discussion and sensitivity analysis There are a number of uncertainties when measuring and valuing greenhouse gas balance, which can lead to a wide range in overall values. Carbon sequestration rates used in previous studies have ranged quite widely. For example, eftec (2015) use a national average of 4.71 and 4.47 tCO2e sequestered per ha per annum for broadleaved and coniferous trees respectively over 10 years old. This is based on the Woodland Carbon Code lookup tables, but uses trees up to 200 years old, which may not be appropriate for coniferous trees which are normally felled at a much younger age. White et al. (2015) and Christie et al.
(2011) use 4.97 and 12.66 tCO2e for broadleaved and coniferous, again based on the Woodland Carbon Code lookup tables, whilst Bateman et al. (2013) used 16.9 and 19.52 tCO2e respectively, based on different studies of carbon sequestration.
I calculated figures of 9.37 and 12.13 tCO2e for broadleaved and coniferous trees in Northamptonshire, which is intermediate to the above studies. However, one of the assumptions that I made was that the woodlands would not be actively managed, and also that the rotation length would be 60 years for coniferous trees and 100 years for broadleaved trees. If these assumptions are altered then the carbon sequestration rates will typically decrease. If, for example, the trees were actively managed through regular thinning then the rates would drop to 5.38 and 7.24 tCO2e for broadleaved and coniferous trees respectively in Northamptonshire. Active management is particularly likely for the coniferous tree stock which is generally found within plantations. In addition, if woodlands were retained for 200 years and not thinned then rates would fall to 5.26 and 5.32 tCO2e respectively. The other major source of variability in carbon valuation is in the choice of carbon price, which varies by more than an order of magnitude. There is a clear consensus that the UK Government non-traded carbon price should be used for accounting purposes. However, there is some logic in also considering the woodland carbon unit price, which reflects the amount of money that a landowner would receive (the exchange value) if the land was entered into the UK Woodland Carbon Code at present, hence it more closely reflects current income possibilities. It is, however, acknowledged that this value is presently too low and that when carbon markets become better established it is predicted that it will increase considerably.
If a lower sequestration rate is used alongside the much lower woodland carbon unit price, then the overall value of carbon sequestration across the whole study area drops from £7.2M to around £300,000 and this can be taken as a lower-bound estimate of the carbon sequestration value across the Nene Valley. Lower prices would also reduce the negative value of agricultural emissions, although a price based on a unit of woodland carbon would not be appropriate.
The answer as to which value to use reflects to a large extent on the purpose of the valuation. If the main purpose is to raise awareness of the overall value of natural capital or to perform ecosystem / natural capital accounting, then the price used here is most appropriate, but if the purpose is to assess the income that could currently be generated from alternative land-uses, then the woodland carbon unit price would be more suitable. The former aims are of interest here, hence the higher price seems more appropriate. However it should be borne in mind that carbon markets are young and hence any valuation is subject to a high level of variability.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6.4 Pollination
6.4.1 Introduction Insect pollinators are essential for human survival and for the natural environment. They pollinate 75% of the native plant species in Britain (Ollerton et al. 2011) and directly contribute an estimated £603 million per annum to the British economy through the pollination of agricultural crops (Vanbergen et al. 2014). Here I estimate the value of pollination for: A. Agricultural crops –primarily oilseed rape and field beans. B. Orchard produce – primarily apples, but also pears, plums and cherries.
6.4.2 Methods There are a large number of different approaches used to model the value of pollination services (Breeze et al. 2016). Here I use a widely used approach that calculates the proportion of the value of the crop that depends on pollinators. To be compatible with the agricultural and orchard production models (Section 6.2) I calculate gross margin (i.e. taking into account variable costs) for pollinator dependent crops and then determine the loss in production that would occur if there were no pollinators. Agricultural crops Pollinator dependent crops in the area were identified as oilseed rape, field beans, and a very small amount of linseed. Initially the same method as employed to value agricultural production was followed (see Section 6.2.2 for further details). Hence crop areas obtained from agcensus were multiplied by the relevant gross margin obtained from Defra’s Farm Business Survey for each pollinator dependent crop. Gross margin for each crop in each grid square was then multiplied by the % pollinator dependency of each crop type, taken from Gallai et al. (2009). Individual crops were summed to give the monetary value of pollinators for each grid square and this was then divided by the area of farmland in each grid square to give the pollination value per hectare of farmland. Finally, the data were imported into GIS and projected onto the agricultural areas of the basemap and resampled at a 1 ha resolution.
Orchards The gross margin of orchard fruit was calculated in the same way as described in Section 6.2.2. Gross margin was then multiplied by the average pollinator dependency of orchard fruits to give the total value of orchard pollination in each grid square. Pollinator dependency was taken from the UK NEA (Smith et al. 2011), with mean dependency adjusted to the mean production value of different orchard fruits in the UK (no local data available) over the last 5 years (Defra 2015). Production value was: dessert apples 45%, culinary apples 28%, pears 9%, plums 8%, cherries 4%, others 6%.
The pollination value for agricultural crops and orchards were added together to determine the overall pollination value for each grid square and mapped. The final map provides values as £ per hectare.
6.4.3 Results for the Nene Valley Agricultural crops and orchard produce are highly variable in their pollinator dependency, with oilseed rape and field beans showing a 25% reduction in the absence of pollinators, linseed only 5%, but orchard produce averaging 80% dependency. This means that although oilseed rape and field beans are spread much more widely over the Nene Valley, orchards show hotspots of high pollination value. This can be seen spatially (Map 46) where orchards appear as small red hotpots, with pollination values of around Natural Capital Solutions Ltd 96
Mapping Natural Capital and Ecosystem Services in the Nene Valley £6000 per hectare per annum, whereas oilseed rape and field beans are spread much more widely (the yellow and orange areas of the map) generating a lower pollination value of typically less than £100 per hectare. The total value of pollination is shown in Table 10, with orchard pollination valued at £0.96M and agricultural pollination valued at £4.58M across the whole study area. Orchard pollination comprises 17% of the total pollination value, whereas orchard production (Section 6.1) only accounts for 1.6% of total food production value.
Table 10: Total value of agricultural and orchard pollination across the study area
Service Nene Valley NIA Nene Valley NIA plus 3 Km buffer Agricultural pollination (£) 1,003,925 4,575,670 Orchard pollination (£) 344,554 955,312 All pollination (£) 1,348,479 5,530,982
6.4.4 Discussion and sensitivity analysis Gross margin data is well established and based entirely on market prices, so is likely to be reliable. Over the last five years gross margin of oilseed rape has ranged from 0.78 to 1.22 times the average used here, whereas field beans have ranged from 0.66 to 1.28. Orchard fruit have varied the least, ranging from 0.94 to 1.05. These price fluctuations would result in the overall pollination value ranging from £1.07-1.60M per annum for the NIA over the last five years, or from £4.31-6.66M for the full study area. Pollinator dependency ratios are perhaps less reliable as they assume average values and do not account for differences between cultivars. In addition, using this approach is actually valuing pollination demand, rather than supply. There is no indication as to whether the natural environment is fully supplying the demand or if there has been a yield penalty due to a lack of pollinators. For example, Garratt et al. (2014) estimated that the market output of Gala apples would increase by £6,500 per ha under optimal pollination conditions compared to the present situation, although there would be little impact on Cox apples. Also, if the amount of pollinator dependent crops were increased in the study area it would show the value of pollination going up without any consideration of pollinator abundance. The valuation above will be an underestimate of the true value of pollination as it does not include the value of pollination to allotments, garden produce, pick-your-own farms, or wild produce (e.g. blackberries, sloes etc.). There is no data available on most of these types of food, hence it is not possible to value these at this time, but the amount of food produced in allotments and gardens is thought to be significant and increasing as interest in home-grown produce has increased over the last decade.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6.5 Recreation
6.5.1 Introduction The importance of access to the natural environment is being increasingly recognised. Visits to natural areas have been shown to enhance physical and mental health and wellbeing, increase social cohesion and contribute greatly to the local economy. A major national survey – the Monitor of Engagement with the Natural Environment (MENE) – commissioned by Natural England, Defra, and the Forestry Commission, has been collecting information on the volume and value of recreational visits to the natural environment since 2009. For example, between March 2013 and February 2014 there were estimated to be 2.93 billion visits made to the natural environment resulting in an estimated spend of £17 billion (Natural England 2015).
6.5.2 Methods First, all areas of publicly accessible greenspace were mapped. These were defined as areas 10m either side of linear routes such as Public Rights of Way, pavements and Sustrans (cycle) routes, together with publicly accessible green infrastructure such as country parks, CRoW access land, local nature reserves, accessible woodlands, parks, playgrounds, and other amenity greenspaces. Next, total recreational expenditure per annum was calculated based on annual number of visits and typical expenditure per visit. Note that this is the number of visits per annum and not the number of visitors, which is likely to be considerably lower. Number of visits was not available on a site by site basis, but was available for larger blocks of land within the study area from the MENE data set. This is based on interviews with 280,790 households across all areas of the country and all seasons over a six year period (2009-15), thus representing a large and robust data set. The following were extracted from the MENE data set: 1. Estimated annual numbers of visits averaged over the 6 years of the survey. The Nene Valley NIA boundary is directly incorporated into the MENE data set, so visits could be extracted easily. For the NIA plus 3Km buffer I used Borough Council boundaries, including the whole borough where most or all of the borough was in the study area, and excluding the whole borough where only a small part of the borough was in the study area. 2. Data on average spend per visit to the study areas. The average spend in the study areas was compared to the national sample and was found to be very similar. I therefore used the national spend projection provided by MENE (averaged over each year of the survey) as it has been adjusted from the national sample to be representative of the wider population. The estimated annual number of visits was multiplied by the average spend per visit to provide a valuation of total recreational expenditure per annum for the NIA and for each local council area. Finally, the total expenditure was divided by the area of publicly accessible greenspace within each block of land, and projected onto a map in GIS. It was aggregated into a 1 ha raster to match the other valuation maps. The final map provides values as £ per hectare.
6.5.3 Results for the Nene Valley According to MENE it is estimated that an annual average of 25.4% of visits resulted in some form of spending (so 74.5% of visits involved no spending). Where spending did occur, an average of £27.56 was spent on the trip on items including petrol, entrance fees, food and drink, bus fares, and car parking.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley Including those that spent nothing, this means that an average of £6.91 was spent per visit to the natural environment over a 5 year period.
The headline figures for annual visits and their value in the study areas are shown in Table 11. The Nene Valley NIA was estimated to receive 13.7M visits per annum, which is a higher number relative to its area than the wider NIA plus buffer (33.4M visits). This means that recreation is valued at £2278 per hectare if spread over the whole area of the NIA, or £1357 per hectare over the whole of the wider study area. The total value of recreational expenditure (Table 11) is £94.4M in the NIA and £230.6M in the wider area.
Table 11: Estimated number of visits and the annual value of these visits
Nene Valley NIA Nene Valley NIA plus 3 Km buffer Average annual visits 2009-14 13.7M 33.4M Value of recreational visits (£) 94.4M 230.6M
The map of recreational value (Map 47) highlights areas that are publicly accessible. The non-linear sites can be seen to have particularly high value. Sites in the Nene Valley NIA, for example, have values of over £20,000 per hectare per annum.
6.5.4 Discussion and sensitivity analysis The value of recreational expenditure is high, and considerably higher than for the other ecosystem services valued across the Nene Valley (see Section 6.6 below). This is driven by the large number of visits made across the study area. The Nene Valley NIA has the second most visits (and the second most spend) out of the 12 original NIAs, only behind Birmingham and the Black Country NIA which is almost entirely urban and has a very large population. The visit number for the NIA is particularly high as this includes all visits to outdoor areas, so will include visits to the major country parks (Barnwell, Irchester, Fermyn Woods, Sywell, and Brixworth), Nene Park in Peterborough, the borough parks, major attractions such as Wicksteed Park, visits to urban parks, and dog walks along the river. Hence many of the visits may well not be strongly related to the natural environment (but they do take place in the natural environment). The assessment of recreation value may be subject to some error in both the estimation of visits and their value. The MENE survey extrapolates from the surveyed sample to estimate annual visits and so can be inaccurate, especially for small or less visited sites. However, I was able to test this for one site against a different estimate of visitor numbers. For the Upper Nene Valley Gravel Pits SSSI the MENE survey estimates that there were on average 1.12M annual visits made in the 2009-15 period. On the other hand, a survey of visitors conducted for the NIA project (Liley et al. 2014) estimated there to be 900,000 visitors annually. Note however, that the Liley et al. (2014) estimate is likely to be an underestimate of visitor numbers as it makes a number of assumptions such as assuming a constant number of visitors year round (and the survey was conducted in the winter and spring). This may be true for regular dog walkers or bird watchers, but visits to the more popular sites (such as Stanwick Lakes) will increase dramatically over the summer. Therefore, based on this one site, the MENE figures do not seem to be excessive. The second source of error may be the estimation of visitor expenditure. Here I have used the average spend recorded in the MENE survey, which seemed reasonable given that it is the largest survey of its kind in the UK and covers all habitats and visit types. However, some recent studies have used Sen et al. (2014), Natural Capital Solutions Ltd 100
Mapping Natural Capital and Ecosystem Services in the Nene Valley who performed a meta-analysis of a large number of different studies of recreational value based on a range of valuation techniques. They reported habitat specific values ranging from £1.54 per visit to grasslands up to £5.36 for greenbelt and urban fringe farmlands. It is difficult to use these figures in the Nene study as there are no definitions of habitats such as greenbelt and urban fringe farmlands and no average value given. However, a simple mean of the four habitats reported in Sen et al. (2014) that occur in the Nene Valley is £3.02, so considerably lower than the £6.91 used in the present study. If this figure was used in the present study, the total value of recreational visits would be £41.2M in the NIA and £100.7M for the NIA plus buffer. Other studies, however, have used higher figures. For example in the first national assessment of UK Natural Capital (Khan et al. 2014), recreation is valued using the travel cost method plus the value of the time spent on the visit. As time is valued at 75% of the average hourly wage, this results in a much higher estimate of the value of each visit. Meanwhile, Christie et al. (2006) determined that cyclists, horse riders, walkers and general visitors to woodlands attained welfare benefits equivalent to £15 per-trip, whilst benefits for nature-watchers was £8 per trip. The recreational expenditure reported here is based on money spent during the trip rather than the expense that people incur in making the trip (e.g. food and fuel bought before the trip). Furthermore it only values expenditure rather than the welfare benefits obtained from the visit, or wider benefits such as enhancements in health and wellbeing. Therefore the value estimated here only provides a partial valuation of the benefits of recreation.
Stanwick Lakes visitor centre at sunset by Louise Frohock
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 6.6 Overall valuation and discussion
Ecosystem services in the Nene Valley have a high monetary value. In particular, the value of recreational visits is exceptionally high. A summary of all annual flow of benefits reported in the previous sections is shown in Figure 6 and Table 12. The annual value of the services assessed is £109.4M in the Nene Valley NIA and 300.6M for the wider NIA plus buffer per annum. Note that the value of pollination is not included in the total, as pollination value is a part of agricultural production and orchard production values, so to include it in the total would be double counting.
250
200
150
100
50 Total value (£M) value Total
0
-50 Agricultural Orchard Carbon Agricultural Greenhouse Pollination Recreational production production sequestration emissions gas balance visits
Figure 6: Annual value of ecosystem services in the Nene Valley NIA plus buffer
Table 12: Annual value of ecosystem services across the study area and lower-bound estimate of value based on the sensitivity analysis.
Lower-bound estimate of Total annual value of services (£M) Annual flow of services annual value (£M) Nene Valley NIA NIA plus buffer Nene Valley NIA NIA plus buffer Agricultural production 16.5 74.7 12.4 56.0 Orchard production 0.43 1.20 0.41 1.1 Agricultural emissions -3.01 -13.0 -0.24 -1.1 Carbon sequestration 1.04 7.15 0.05 0.3 Greenhouse gas balance -1.97 -5.89 -0.19 -0.8 Pollination 1.35 5.53 1.07 4.3 Recreational visits 94.4 230.6 41.2 100.7 Overall value of ES 109.4 300.6 53.8 157.0
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Mapping Natural Capital and Ecosystem Services in the Nene Valley Note that this valuation has only considered a few ecosystem services on which it is possible to provide a monetary value. If it were possible to place a monetary value on more ecosystem services, then the overall value of the natural environment in the Nene Valley would be seen to be even greater that the figures reported here. But by considering this valuation alongside the quantification and mapping of services completed in Sections 4 and 5, a more complete understanding of the provision and value of ecosystem services in the Nene Valley has been obtained. Furthermore, by mapping these values spatially, it’s possible to highlight exactly where the services are being delivered and the change in value from place to place.
6.6.1 Asset value The annual values can be converted to an asset value for the stock of natural capital in the study area (Table 13). This applies standard discounting rates over 50 years to calculate the present value. In all cases this assumes a constant price for each ecosystem service over the next 50 years, although in reality prices may not stay constant.
Table 13: Asset value (present value) over 50 years with standard UK Government discounting rates applied.
Nene Valley NIA Nene Valley NIA plus 3 Km buffer Agricultural production (£M) 422.2 1,911.2 Orchard production (£M) 11.1 30.7 Agricultural emissions (£M) -76.9 -333.7 Carbon sequestration (£M) 26.6 183.0 Greenhouse gas balance (£M) -50.3 -150.7 Pollination (£M) 34.5 141.5 Recreational visits (£M) 2,415.6 5,897.9 Overall asset value over 50 years (£M) 2,798.5 7,689.1
6.6.2 Value per hectare The value of ecosystem services per hectare reveals that the Nature Improvement Area has higher value than the wider area (Table 14). The value of many of the services is approximately equal, but the value of carbon sequestration is highest in the wider area, reflecting the fact that there are few wooded areas close to the river. However, most striking is the difference in the value of recreational visits. It is estimated that 41% of all visits made to the wider area take place in the 24% of the land that comprises the NIA, giving it a recreational value of £2,278 per hectare per year. It is not clear whether people are particularly attracted to the habitats found close to the river or whether these areas are simply more likely to have publicly accessible sites, but either way, the value of the NIA is clear. Furthermore, this estimate is an underestimate of true recreational value as it does not include the true cost of travelling to the site, the value that people place on their visit, or the health and wellbeing benefits that they receive. It is interesting to note that the recreational value of the NIA is far higher than if it was managed purely for intensive arable production. Natural Capital Solutions Ltd 104
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Table 14: Annual flow of ecosystem services per hectare across the study area.
Annual flow of services Nene Valley NIA Nene Valley NIA plus 3 Km buffer Agricultural production (£/ha) 398 440 Orchard production (£/ha) 10 7 Agricultural emissions (£/ha) -73 -77 Carbon sequestration (£/ha) 25 42 Greenhouse gas balance (£/ha) -47 -35 Pollination (£/ha) 33 33 Recreational visits (£/ha) 2278 1357 Overall annual value of ES (£/ha) 2639 1769
6.6.3 Variations in value Valuing ecosystem services is not an exact science; non-market prices are highly variable, there is not always consensus on the most appropriate methodology to use, and even for market-based methods there are fluctuations in value year-on-year. I have tried to discuss such issues wherever possible and have included lower bound prices in sensitivity analyses (these are shown in the right-hand column of Table 12). Most of these differences arise from the valuation element of the respective approaches, rather than from measuring the physical flows. The service with the greatest degree of difference in the value given here and its lower-bound estimate is for greenhouse gas balance, where the use of alternative carbon prices causes a greater than 10-fold difference in value. The lower-bound estimate is based on market transactions for woodland carbon, but this is more a reflection of the regulatory framework and institutional factors than the true value of the ecosystem service (eftec 2015). There is growing consensus amongst academics, practitioners and government that the higher non-traded carbon price should be used to value carbon. This value has been calculated based on marginal abatement costs and reflects the costs of achieving political targets related to climate change. The largest absolute change in monetary value when considering lower-bound estimates is for recreational visits, simply because the values for this service are so large. However, this value can also be much higher if applying a different method, such as calculating a value for time spent, as adopted by the UK Government (Khan et al. 2014). The values of agricultural and orchard production and pollination are less variable, primarily as they are based on long established market prices, although even these fluctuate in line with changes in global commodity prices.
Perhaps a message that can be drawn is that there is inherent variability in ecosystem service values, but that the relative values are approximately stable. Even when considering lower-bound estimates, the value of recreational expenditure is still several times greater than the value of agricultural production, which is itself several times greater than greenhouse gas balance and pollination. These relative values can be highly informative, particularly in regard to raising awareness of the value of the natural environment and in land-use planning. It is likely that as ecosystem accounting and other uses for these types of valuations become more established, methods and prices will become more consistent and variability will decrease.
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7. Natural capital and ecosystem services in the Nene Valley
The Nene Valley is a landscape shaped by the interactions between people and the natural environment. At its core lies a series of flooded gravel pits; the result of industrial activity, but now reclaimed for and by the natural environment, but also delivering benefits to people. The wider catchment, too, consists of farmland interspersed by towns and villages, but also containing patches of ancient woodland and small remnants of semi-natural grasslands. This natural capital delivers a wide range of benefits to people, many of which are unrecognised or undervalued in decision-making. Balancing the needs of recreational access, biodiversity conservation and agricultural production has been a challenge for a number of years, although the relative value of recreational activities to the local economy has generally been underestimated. More recently the role of natural capital in providing carbon storage and sequestration, ameliorating air pollution, enhancing health and wellbeing, delivering water quality benefits and reducing downstream flood risk is beginning to be recognised and is becoming highly topical. The Nene Valley is particularly interesting area to study as it is typical of the English lowlands; it does not contain numerous semi-natural habitats or a National Park, but it does provide important benefits, it is valued locally and is facing increasing pressure from development. As such, it provides an excellent case study highlighting the benefits and value of the natural environment in a “normal” landscape. It demonstrates the use of natural capital and ecosystem services approaches and how they can be used to inform decision making and influence planning and development. The aim of the work presented in this report has been to assess the ecosystem services (the benefits) delivered by the Nene Valley across the landscape in a spatially accurate way, to highlight the demand for these services, and to place a monetary value on some of the services being delivered. By producing highly detailed maps at a resolution much beyond anything previously undertaken, it is possible to start examining trade-offs and synergies, and the hotpots and coldspots in the provision of individual and multiple ecosystem services. This can be used to determine areas that are delivering services that require protection and areas where more could be done. The maps also form a baseline from which it is possible to assess opportunities to create habitats for a given purpose such as air quality enhancements or natural flood risk management, or to highlight areas that will benefit multiple objectives. Finally, the maps and accompanying monetary values are an important tool in raising awareness of the value of the natural enlivenment to society and to the local economy. The maps highlight the importance of woodlands and the River Nene corridor at delivering multiple ecosystem services. Furthermore, monetary valuation has revealed the highly significant contribution that natural capital makes to the local economy. The majority of this value is derived from expenditure on recreational visits, illustrating the importance of the publicly accessible sites along the river valley.
7.1 Hotspots and coldspots, trade-offs and synergies Maps 37 and 38 provide summaries of the key areas delivering multiple benefits in the Nene Valley (the hotpots), or delivering very little across a range of services (the coldspots). It is quickly apparent that the woodland patches and river corridor are delivering the most benefits. These areas are delivering high levels of carbon storage, noise regulation, air purification, water quality and water quantity (slowing the flow) benefits, and are also largely publicly accessible, delivering high levels of tranquillity and accessible nature.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley By also examining demand for ecosystem services and placing a monetary value on some of the benefits, it’s possible to gain additional insight and a much more nuanced picture of the ecosystem services provided across the Nene Valley and their relative importance. Benefits arising from noise regulation and air purification, for example, are highly localised and are much less relevant in areas away from population centres where noise and air pollution may be low and there may be few people to benefit. Thus the benefits of some of the more isolated patches of woodland may be overstated by Maps 37 and 38. On the other hand, woodland in and around the large urban areas can be far more important as they are delivering these additional services and are likely to receive more visits. The river corridor is especially important in this respect, as it brings semi-natural habitats into the heart of the urban areas. It also provides a natural corridor, enhancing the movement and connectivity of both people and wildlife. When also considering the additional information provided by monetary valuation, it becomes clear that recreation is far more important than any of the other ecosystem services valued. This means that publicly accessible sites are much more valuable than private areas and the river corridor gains added significance. There is a significantly higher proportion of accessible sites along the river corridor (in the core NIA area) than in the wider catchment, and many of these are highly visited sites such as Nene Park (Ferry Meadows), Stanwick Lakes, Wicksteed Park, Pitsford Reservoir, several of the County Council owned country parks, as well as a number of urban parks. Thus the relative value of the core NIA is greater than first appears when examining the ecosystem services maps. From the above it is possible to identify ways to deliver multiple benefits and to achieve maximum value. This can most obviously be achieved by creating publicly accessible habitats close to urban areas. New woodlands can deliver carbon storage and sequestration benefits, together with noise and air pollution amelioration, water quality, water quantity, and accessible nature benefits, whilst achieving biodiversity enhancement. Woodland is not appropriate in all locations, but all publicly accessible natural greenspace is valuable. The most significant coldspots for overall ES delivery are the urban areas. However, these areas are providing the key demand for the services provided. Demand for ES is generally centred in urban areas and the areas of countryside surrounding towns are often subject to high levels of public use. By enhancing access to and management of areas close to urban areas, it would be possible to significantly enhance local benefits, without negatively impacting on the biodiversity in the core parts of the Upper Nene Valley Gravel Pits SPA. In terms of potential trade-offs, the most obvious example is between food production and most of the other services. Extensifying agricultural production would generally increase the production of water quality, water quantity, carbon storage and accessible nature services. However, there is a balance to be struck between environmental enhancement and rural (farmer) livelihoods, and the opportunities of paying farmers for the enhancement of environmental benefits (Payments for Ecosystem Services) is a key to the long term viability and sustainability of such approaches (see Section 7.3 below for more on this). Another important trade-off, is that between public access and tranquillity and biodiversity. Breeding waders are also particularly sensitive to public access (especially dogs) and so increasing access and hence accessible nature, could have a detrimental impact on these species. This can be managed by providing accessible sites close to people’s homes for regular access including dog walking, limiting development within 3Km of the core SPA, and by carefully managing key sites through screening, zonation and other practical solutions.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 7.2 Some applications of natural capital and ecosystem services mapping
7.2.1 Maps show where investment and management should be targeted The ecosystem services maps highlight hotspots, where current land use should be continued and supported, and coldspots where change could be beneficial. The maps can be used at a broad scale or at a very fine local scale. At a broad scale, they can be used to identify general rules and objectives for the management of swathes of landscape. The high resolution of the mapping can be used to distinguish changes in ES delivery across small distances in the landscape. This fine level of detail is important when planning the most appropriate management actions at a local (field) scale. At this scale the maps can be used to highlight particular fields that would benefit from land use change or should be kept how they are. For example, land close to watercourses may particularly benefit from a land use that is able to slow the flow and deliver water quality, biodiversity and other benefits at the same time. Trees planted next to busy roads can be particularly beneficial at absorbing pollutants and reducing noise. Overall, the information could be used to produce general rules and guidelines for the most appropriate management in different locations and specific opportunities for habitat change at targeted locations. In all cases, however, opportunities require ground-truthing as local conditions have not been incorporated into the mapping work. Other factors, particularly the views of the land-owner will also become paramount in taking opportunities forward.
7.2.2 Working with the planning system A key objective of the Nene Valley Nature Improvement Area Project was to work with the planning system so that growth and development would support, value and benefit the natural environment, resulting in net gain in biodiversity. Taking a natural capital / ecosystem services approach is a key way of achieving this objective. Indeed, the NIA project team worked with local planners to embed the concept of ecosystem services into the North Northamptonshire Joint Core Strategy, which was officially adopted in July 2016 and will guide development until 2031. This recognises the importance of ecosystem services and delivering multifunctional landscapes, and requires that all new developments enhance the provision of ecosystem services where demand exists. The assessment presented here can be an important contributor to the planning process. The maps can be used as evidence for Local Plans Part 2, and Green Infrastructure Delivery Plans, highlighting key locations for protection or enhancement and raising awareness of the multifunctional benefits of the natural environment and their value. At a more local scale they can also be used as input into the planning of major development projects, highlighting the ecosystem services prior to development. If the models are re-run incorporating the development plan, they can show the change in ES delivery due to the proposed development. It would also be possible to use the models to optimise masterplanning in an iterative process, whereby a number of alternative designs are tested to determine the one(s) that delivered the greatest overall benefit across a range of ecosystem services.
7.2.4 Delivering multifunctional landscapes The maps can be used as a first step to achieving multi-objective land management, guiding new projects and developments that achieve a net gain for natural capital and ecosystem services. There is growing awareness of these ideas amongst some in government agencies and NGOs, but there is a need to really promote this to land-owners and managers. Funding is also often tied to a single objective, making it difficult to deliver projects that are truly multifunctional.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley 7.2.3 Spatial modelling of future scenarios The current basemap can be altered to show the potential landuse and habitats under future scenarios and the ecosystem services models then re-run to determine potential impacts. In this way, the effect of planning proposals, changes in policy, economic or environmental factors can be modelled. This can reveal risks and opportunities, and enables mitigation to be planned and proposals to be adjusted.
7.2.5 Stakeholder engagement The maps can be used to inform dialogue with stakeholders and the public and raise awareness of the benefits of the natural environment. They can be used to engage with different sectors such as planners and developers, or the water sector.
7.2.6 Payments for Ecosystem Services (PES) schemes The values revealed can be used as a basis for setting up PES schemes and other ecosystem markets. This is described in more detail in the next section. They can also be used as part of natural capital accounting.
7.3 Payment for Ecosystem Services Schemes and other opportunities Payment for Ecosystem Services Schemes, commonly referred to as PES Schemes, are simply any scheme where the land holder / manager is paid to deliver an ecosystem service or bundle of services, by the beneficiaries of that service. There has been a lot of government interest in such schemes over the last few years, with a number of pilot projects supported by Defra and Natural England. Some of the key PES approaches that are relevant to the Nene Valley, and other opportunities to promote natural capital and ecosystem services, are shown below:
UK Woodland Carbon Code – the amount of carbon that can be sequestered by planting woodland can be accurately estimated and this carbon has a monetary value (as shown in Map 43). Polluters pay for woodland to be planted to offset their emissions. This scheme is well developed now and fully operational, but uptake is limited as carbon offsetting is not yet compulsory for UK businesses. There is, however, great potential for this to take off should the government decide to legislate, with particular benefit to areas such as the Rockingham Forest. Slowing the flow – regular flooding events over the last few years have given added impetus to the idea of natural flood risk management in the headwaters and this is an area that is being actively pursued by the Environment Agency, Natural England and others. A number of successful pilots have been run over recent years and have shown great promise, but again the challenge is to persuade beneficiaries to pay for this type of scheme, especially when outcomes are inherently less certain than for traditional concrete schemes. There is, however, a statutory requirement for new flood risk management schemes to provide significant environmental gain, and a greater emphasis on delivering multi-functionality. Water quality – the idea here is that water companies pay for upstream management works to improve water quality and thereby reduce the cost of water treatment. There are very good examples from the Upstream Thinking Project funded by South West Water and the SCaMP project paid for by United Utilities in the Pennines. In addition, many actions for the Water Framework Directive (WFD) require catchment scale approaches that focus on improving water quality through appropriate land management. In the Nene Valley, metaldehyde (used in slug pellets) is a major concern for Anglian Water as it cannot be effectively removed from drinking water once present. Natural Capital Solutions Ltd 109
Mapping Natural Capital and Ecosystem Services in the Nene Valley Leaving a wide unploughed buffer around watercourses and drainage ditches can be effective at reducing the risk of contamination and will simultaneously deliver other benefits, such as reducing sediment and water runoff. Farmers can also be paid to switch the chemical that they apply to treat slugs. Anglian Water is presently working with farmers in some parts of the Nene catchment on these types of approaches. Countryside Stewardship – the government’s agri-environment scheme is effectively a type of PES scheme. The focus is predominantly around biodiversity conservation and lower intensity farming, but it can also incorporate other elements such as enhancing public access, water quality (through WFD measures) and flooding issues. Following the Brexit vote there is a great deal of debate going on about the future of these types of schemes, with much interest (at least from the conservation sector) on the possibility of expanding the ecosystem services elements of these schemes. This is a subject that is likely to be given serious consideration in the forthcoming 25 year food and farming and environment plans being produced by Defra. Biodiversity offsetting and net positive schemes – this is where any loss of habitats through new development has to be offset through habitat creation or restoration elsewhere. The government has not yet decided on whether to pursue this policy and how local the offsets have to be to the habitat being lost, but it has the potential to deliver a lot of money for biodiversity conservation projects. Meanwhile, a number of organisations such as Network Rail are already starting to deliver their own schemes, with the aim being that there is either no net loss, or a net gain (net positive) in biodiversity following new development works such as the electrification of the Midland Mainline. There is a clear opportunity to work with such organisations, by developing costed project proposals that are ready to create or restore habitats to offset such losses. Community Infrastructure Levy (CIL) and Section 106 – also known as planning gain; this is the means by which developers pay for green infrastructure (and other community benefits) in areas close to new developments. This has huge potential in areas such as the Nene Valley where a large number of major developments are going to take place over the next few years. Although the majority of monies are likely to be spent on grey infrastructure, if strategic options and local plans for green infrastructure are already in place then money from CIL and S106 can more easily be allocated to these projects. Sustainable Drainage Schemes (SuDS) and water-sensitive urban design – Buildings Regulations promote the use of SuDS to deal with surface water runoff for all new developments. SuDS and other water-sensitive design features are therefore likely to feature in all major new developments being planned in the Nene Valley. Such features can also deliver additional ecosystem services benefits, such as enhancing water quality, reducing the urban heat island effect, opportunities for recreation (in and around the larger features) and providing green habitats within the heart of urban area. Health and wellbeing – there is a growing recognition of the importance of access to the natural environment in enhancing wellbeing and improving health, particularly around chronic lifestyle conditions related to inactivity and stress. Unfortunately the growing evidence base has so far only had limited impact on policy. However, this does offer great potential, particularly with the creation of health and wellbeing boards and organisations with specific remit for these areas, and is one to watch. For example in Northamptonshire a community interest company called “First for Wellbeing” has recently been formed, bringing together health and wellbeing services previously
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Mapping Natural Capital and Ecosystem Services in the Nene Valley provided by Northamptonshire County Council, Northamptonshire Healthcare NHS Foundation Trust and the University of Northampton. Angling passport schemes – these have been set up in a number of rivers around the country. In essence, anglers pay for access to rivers, with the money being spent on improving the ecological quality (and thereby fisheries) along that stretch of river. However, following some initial enquiries it became apparent that there are a large number of different fishing organisations with fishing rights to different parts of the Nene, with little co-operation between them, and the prospects of setting up a scheme here was considered to be unlikely. Corporate social responsibility and accounting – these initiatives are taken increasingly seriously by some companies and cover a range of environmental and social impacts. Since 2013 the Companies Act 2006 (Strategic Report and Directors’ Report) Regulations 2013 has required all UK quoted companies to report on their greenhouse gas emissions as part of their annual Directors’ Report. Through corporate social responsibility programmes, some companies will take this further by offsetting this carbon through schemes such as the Woodland Carbon Code (above). In addition the Natural Capital Coalition is working with businesses (including land owners and managers) to promote the development of corporate natural capital accounting and there are now a growing number of examples from the private sector. It is hoped that by accounting for the natural environment in business, it will lead to better, more sustainable management and decision-making.
The key challenge in delivering many of the PES schemes described above is in encouraging or making it compulsory for beneficiaries to pay for environmental benefits that they have previously received for free. This is an area of active development at present but may ultimately depend on government legislation. Recognising and accounting for the natural environment is, however, an important step in this process. Another challenge where land owners are receiving payment from others for delivering ecosystem services is around security of payment for the long term. In most cases, significant land use change to more semi- natural habitats requires a long-term commitment by the land manager and is not quick or cheap to reverse. Land managers are likely to be reluctant to do so when future funding is so uncertain. This may resolve once (if) PES schemes become established, but is a challenge at present. Even Countryside Stewardship is often only available for 5 years now, rather than 10, and there is even more uncertainty now, following the vote for Brexit.
7.4 Further work The natural capital and ecosystem service mapping and valuation presented here provides a detailed baseline and evidence base to inform decision making in the Nene Valley. It also provides an opportunity to carry out further studies that builds on this work. Here I present what I consider to be the most useful ideas of how additional work could provide further benefits and added value to that already done, although please note that this list is not exhaustive.
7.4.1 Conduct further research into the links between natural capital and ecosystem services There are numerous opportunities to perform further analyses of the existing data and maps, to provide additional insight into the links between natural capital and ecosystem services (ES). Of particular interest would be an analysis of the co-occurrence of multiple ES, examining tradeoffs and synergies between different ES and which habitats they are dependent upon. This could be used to reveal bundles of ES that
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Mapping Natural Capital and Ecosystem Services in the Nene Valley are associated with particular locations and habitats and that could form the basis of multi-functional land management and Payments for Ecosystem Services schemes. In addition, there is much further work that could be conducted on the links between ES and biodiversity, and to explore the patterns of biodiversity in more detail. For example it would be interesting to examine the drivers of species richness for each taxonomic group, which could be then be used to model richness over locations where there is currently no data.
7.4.2 Continue to integrate ecosystem services into planning policy and new developments One of the strengths of the wider NIA project has been working with planners and developers, and the project has already collaborated closely with the North Northants Joint Planning Unit, including embedding ES into the recently adopted North Northants Joint Core Strategy. This work is continuing and in addition, specific projects that we are working on include: Writing an introduction to ecosystem services for planners and developers – this will provide important guidance to accompany the North Northants Joint Core Strategy, as well as being a stand-alone document for wider use in the planning sector. Deenethorpe garden village and other proposed major developments – there is the opportunity to influence the planning of major developments across the study area and in particular the proposal to build a new garden village at Deenethorpe. It would be possible to perform an ecosystem services assessment of the proposed development, to determine alterations that could be made to the masterplan to enhance ES delivery, or to perform natural capital accounting on the proposals. The ecosystem services maps and values provide evidence to feed into Local Plans Part 2 and this can be taken further by examining opportunities for the creation or protection of habitats.
7.4.3 Habitat opportunity mapping The maps shown in this report have highlighted the current provision of ecosystem services across the Nene Valley. The principal behind habitat opportunity mapping is to identify areas where new habitat can be created to enhance natural capital and ecosystem services, taking into account constraints such as infrastructure, urban areas, and existing BAP habitats. Maps can be created for any number of opportunities, ranging from biodiversity enhancement, to opportunity to slow surface runoff, to opportunities to ameliorate air pollution, and opportunities to enhance many other ecosystem services. When more than one opportunity map has been created it is also possible to overlay the maps to highlight areas where new habitat can deliver multiple benefits. A project proposal for habitat opportunity mapping has been presented to a number of partners working across the Nene Valley and has recently been awarded funding. Both the North Northants Joint Planning Unit (JPU) and the West Northants JPU are partners for this project, which together represent all seven local authorities in Northamptonshire, and the work will provide evidence for a number of Local Plans Part 2 (as in previous section). The mapping will also inform the best locations for new meadow creation through the HLF funded Nenescape project. The final report on this new work will be available in spring 2017.
7.4.4 Natural Capital Investment Plan Natural Capital Investment Plans (NCIPs) are a relatively new idea, with the first pilot NCIP produced for the Northern Upland Chain LNP, funded by Defra and published in early 2016. In essence they are about establishing and presenting the business case for investing in natural capital (generally though habitat
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Mapping Natural Capital and Ecosystem Services in the Nene Valley restoration or creation). An NCIP is typically applied separately for each major habitat type (e.g. woodlands, semi-natural grasslands etc.) and highlights the current stock and value of natural capital (an asset check). It then identifies opportunities for habitat creation / restoration, either in the form of a general target (x ha of woodland) or a specific plan at specific locations. The next step is to measures costs (capital and operational expenditure) and benefits of this work in monetary terms, typically presented as Net Present Value over 50 years, and to calculate the cost-benefit ratio. The NCIP presents the case for investment and identifies investment vehicles, such as the UK Woodland Carbon Code, with the end product being a prospectus that can be presented to businesses and other interested parties. NCIPs are being strongly promoted by Defra at present and are likely to feature heavily in the forthcoming 25 year plan. It would be beneficial to produce NCIPs for the Nene Valley or Northamptonshire, with large parts of the necessary background work already completed here and in the opportunity mapping project (Section 7.4.3). This would mean that the locations and projects identified through opportunity mapping could be costed and presented to provide a tangible plan for the area to take forward for investment. NCIPs for different habitats can be combined to produce an overall Natural Capital Investment Strategy for the area.
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Mapping Natural Capital and Ecosystem Services in the Nene Valley References
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