DEPARTMENT for ENVIRONMENT, FOOD and RURAL AFFAIRS CSG 15 Research and Development Final Project Report (Not to be used for LINK projects)
Two hard copies of this form should be returned to: Research Policy and International Division, Final Reports Unit DEFRA, Area 301 Cromwell House, Dean Stanley Street, London, SW1P 3JH. An electronic version should be e-mailed to [email protected]
Project title CHALK GRASSLAND: ENHANCEMENT OF PLANT AND INVERTEBRATE DIVERSITY THROUGH THE USE OF ENVIRONMENTAL LAND MANAGEMENT SCHEMES
DEFRA project code BD1414
Contractor organisation CABI Bioscience, Bakeham Lane, Egham, Surrey TW20 9TY and location
Total DEFRA project costs £ 530, 533
Project start date 01/09/1997 Project end date 31/03/03
Executive summary (maximum 2 sides A4)
1. Over the last 50 years, agricultural intensification has led to the loss of large areas of habitats important for wildlife, such as species-rich grasslands. The loss of chalk grassland, considered the most diverse plant community in England, has been particularly great. 2. At the heart of DEFRA’s conservation policy are agri-environmental schemes, particularly Environmentally Sensitive Areas (ESAs) and Countryside Stewardship Schemes (CSS). Two Environmentally Sensitive Areas, the South Downs ESA (SD) and the South Wessex Downs ESA (SWD) contain substantial areas of chalk grassland. Additionally, relatively large tracts of land underlain with chalk soils occur outside these two ESAs (e.g. the Chilterns). In these areas, the Countryside Stewardship Scheme offers incentives for adopting practices which enhance existing areas of chalk grassland or recreate species-rich grassland on cultivated land. 3. This project aimed to identify factors that effectively conserve and enhance the biological diversity of chalk grasslands, in particular identify/ examine relationships between site characteristics, management practices and invertebrate diversity. Multisite surveys and experimental field experiments were the approaches adopted. 4. Experiments examined supplementary mechanisms to enhance diversity: Hay spreading - using hay from an existing species-rich grassland examine subsequent changes in botanical diversity and colonization by invertebrates; and Scrub clearance - examine subsequent vegetation and invertebrate community development on abandoned chalk grassland. 5. The multisite survey provided a broad scale assessment of four grassland types: Unimproved (target community); semi-improved; improved; arable reversion. This work was based in two ESAs - South Downs and South Wessex Downs and CSS in the North and Berkshire Downs, Chilterns, and the Isle of Wight.
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6. The multisite assessment showed that there was geographic separation of sites which affects invertebrate diversity and structure and that the different management prescriptions for ESA and CSS affected invertebrate communities. The ESA sites were a landscape characterised by Chalk Grassland, botanically species rich. However, the CS sites were more conservation biased or on a smaller scale. These sites often consisted of rank tussocky grasses. Although not botanically diverse, these sites were structurally variable which was good for the invertebrate communities. The big difference between the ESA and CSS sites was the arable reversion grasslands. In the ESA, reversion occurred early in the scheme and was sown with ryegrass and clover. In the CSS, reversion occurred post 1992 and was sown with Chalk Grassland species (forbs and grasses), hence better for invertebrates and i9nstantly closer to the “target communities”. 7. Hay spreading was found to lead to an increase in the plant species richness, but over the course of the project, this did not affect invertebrate diversity. Scrub clearance led to an early increase in invertebrate abundance and diversity, which decreased as the “new” sward developed. 8. Invertebrate diversity, abundance and structure were all greater when there was a greater diversity of vegetation structures. Agri-environment scheme policy needs to incorporate further measures to encourage stakeholders to manage for a variety of vegetation structures, whether it is through differential grazing or a more manipulative management programme. 9. The ESAs in particular are successful in meeting conservation of chalk grasslands as detailed by the UK BAP and the EU Habitats Directive. 10. The ESA and CS schemes in their present form are a success in meeting the conservation of chalk grassland conservation as stipulated by the UK BAP and the EU Habitats Directive. Semi-improved and improved sites, when considered by the NVC, are CG2 or CG3, particularly if the sites are in the ESA scheme. Indeed, very few unimproved sites can be considered as poor conservationally. The NVC is an equally good if not better categorisation of the sites monitored than the site characterisation into unimproved, semi- improved, improved and arable reversion. 11. Site isolation, aspect, slope, grazing (stocking rate and type of animal), vegetation classification (NVC and category –U, SI, I and AR) are all identified as important factors in determining the success or failure of chalk grassland restoration/enhancement for invertebrates. 12. Nine recommendations are made, the majority suggesting further research is needed. 13. The use of tools such as scrub clearance and hay spreading clearly have advantages in helping farmers achieve the aims of the scheme. However, a lot more work needs to be done to aid policy revision in this area. For example, the perception that scrub is “bad” needs to be addressed; scrub enhances the botanical diversity and structure and so supports diverse invertebrate communities, so perhaps limited scrub is a good thing on sites. 14. These general conclusions reflect those detailed in the Economic Evaluation of the CSS where there was a comparison of ESA vs. CSS. In this report, it was noted that the CSS focused on environmental improvement through policy directed by quality while the ESA had a clear focus on safeguarding the environment rather than paying farmers to improve the situation.
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Scientific report (maximum 20 sides A4) 1. Introduction Over the last 50 years, agricultural intensification has led to the loss of large areas of habitats important for wildlife, such as species-rich grasslands. Consequently, there has been a significant reduction in the biological diversity of agricultural landscapes. The loss of chalk grassland, considered the most diverse plant community in England, has been particularly great. For example, Newbold (1989) reported losses or serious damage to over 80% of calcareous grassland in the UK between 1949 and 1989 with the situation not improving since then. The large area of chalk grassland lost in the last 50 years was primarily because of changes in agricultural practices. The main causes include the conversion of land for the cultivation of arable crops and the improvement of areas of permanent pasture by the application of fertilisers, herbicides and pesticides (Blackwood and Tubbs 1970; Keymer and Leach 1990). In addition, many areas of unimproved chalk grassland have been completely lost, or have had their biological diversity diminished, through the encroachment of scrub. Scrub invasion occurs when the grazing pressure is too low. A decline in the profitability of livestock production in lowland areas of England and conversion to arable farming has resulted in abandonment of grasslands on land inaccessible to machinery. Chalk grassland is an agricultural system which is the product of many centuries of extensive grazing, primarily by sheep. Large tracts of south-eastern England were once covered by such grasslands (Smith 1980). The dryness and infertility of the soil, combined with the effects of grazing, generally results in a plant community of exceptionally high diversity (Rodwell 1992). Chalk grassland is the sole habitat of 11 plant species scheduled in the Wildlife and Countryside Act and a further 10 Red Data Book plant species. A further 29 Red Data Book plant species occur in chalk grassland along with other habitats. Chalk grasslands also support a highly diverse invertebrate fauna, including many Red Data Book species as well as some species scheduled in the Wildlife and Countryside Act. As a result of their high biological diversity, a Habitat Statement for chalk and other calcareous grasslands is included in the report of the Biodiversity Steering Group (Anon 1995). Chalk grassland is also listed as a priority habitat in the EU Habitat and Species Directive, partly as a result of its large populations of many rare species of orchid (Jefferson and Robertson1994; McLean 1990). For the past 17 years, MAFF (now DEFRA) has been aiming to balance rural interests, countryside conservation and the needs of the farming community/ industry. This has been even more prevalent since the restructuring of MAFF into DEFRA relatively recently. At the heart of the conservation policy are agri-environmental schemes, particularly Environmentally Sensitive Areas (ESAs) and Countryside Stewardship Schemes (CSS). Two Environmentally Sensitive Areas, the South Downs ESA (SD) and the South Wessex Downs ESA (SWD) contain substantial areas of chalk grassland. Additionally, relatively large tracts of land underlain with chalk soils occur outside these two ESAs (e.g. the Chilterns). In these areas, the Countryside Stewardship Scheme offers incentives for adopting practices which enhance existing areas of chalk grassland or recreate species-rich grassland on cultivated land. At the start of this project in 1997, approaching 10,000 ha of existing calcareous grassland have been entered into management agreements in ESAs, along with approximately 15,000 ha of similar grasslands entered into CSS (during the initial 5-year pilot scheme). Environmental Land Management Schemes, which incorporate ESAs and CSS, are aimed at encouraging the preservation of biological diversity and important landscape features on agricultural land through the adoption of environmentally beneficial farming and management practices. However, many factors can potentially constrain the success of such schemes. These include site factors, such as soil characteristics, topography and previous land use, and management practices.
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Factors limiting the enhancement of chalk grassland biodiversity: One of the major factors limiting the enhancement of diversity of sites on which chalk grassland is being restored or recreated is the availability of potential colonists in an intensively-farmed landscape. The fragmentation of chalk grassland and the isolation of the remnants of this habitat have the result that sources of potential colonists occupy a very small fraction of the landscape. Therefore, the proximity of a chalk grassland restoration or arable reversion site to existing areas of unimproved chalk grassland will have an important effect on the colonisation of the site by species characteristic of such habitats (Gibson and Brown 1991; Hutchings and Booth 1996). The problem can be overcome by the artificial introduction of the species to a new site. For plant species, this is comparatively easy and can be done by sowing seed (Wells 1983; 1991; Wells et al. 1981). However, the cost of seed of many of the rarer species of wild flower, characteristic of unimproved chalk grasslands, may be prohibitive (Anon 1996). The manipulation of the colonisation of a site by animals is much more difficult. Measures, such as the spreading of hay taken from existing areas of species-rich grassland, whilst primarily aimed at introducing seed, may have the additional effect of aiding the colonisation of a site by certain species of invertebrate. Factors specific to improved chalk grasslands: High soil fertility in areas of improved pasture may constrain the enhancement of species diversity. If soil fertility is high, plant species with high competitive ability tend to oust less competitive plant species which often have a higher conservation value. Swards characteristic of high soil fertility are dominated by coarse grasses and contain “weeds”, such as nettles and thistles. The on-going management of the site is likely to have an important effect on the development of the plant and animal communities. Grazing and mowing are likely to reduce the abundance of weed species, limit the dominance of coarse grasses and allow the successful colonisation and growth of less competitive species of plant (Gibson and Brown 1991; Gibson et al. 1987; Gibson and Brown 1992; Wilson 1992) leading to a higher biological diversity. The importance of such management for the enhancement of botanical diversity and supplementary measures to promote the enhancement of plant diversity, such as the strip-seeding or broadcast sowing of seed mixtures or the use of modular- grown transplants, are being/ have been investigated (e.g. BD0303, BD0314). Factors specific to abandoned chalk grassland: After the cessation of grazing or reductions in grazing pressure, chalk grassland is often quickly invaded by scrub and may loose much characteristic biodiversity. The soils occurring under areas of scrub which have developed on abandoned chalk grasslands may well contain seeds or other propagules of chalk grassland plants, thus providing a potential supply of new recruits to the vegetation after scrub clearance. However, areas of open scrub and rank grassland often support large populations of invertebrates (Kirby 1992), including rare species such as the Duke of Burgundy Fritillary. Factors specific to arable reversion schemes: The high soil fertility and seed bank of land taken out of arable cultivation will have an important effect on the nature of the vegetation that colonises it. Consequently, after abandonment the sward may be characterised by a high abundance of weed species (Graham and Hutchings 1988a, b). However, the abundance of such weeds often declines fairly rapidly in the years after abandonment, especially if the land is spring grazed, as perennial plant species establish (Gibson et al. 1987). The problem can be countered by sowing a grass seed mixture, thus accelerating the production of a closed sward in which weed species are less able to thrive (Wells 1983; 1991; Wells et al. 1981). Invertebrates as indicators of chalk grassland condition: Chalk grasslands support a rich invertebrate fauna with many species restricted to this habitat (Keymer and Leach 1990; McLean 1990). The highest diversity is found on sites with a range of vegetation structure, from short turf through to scrub (Kirby 1992). In general, highest abundances of invertebrates are found in areas of taller turf (Brown et al. 1990). However, invertebrates of tall chalk grassland tend to be common, whereas those of short turf are rare and can easily be lost through poor site management (Kirby 1992). Invertebrates make good biological indicators as a result of their short life-cycles and their precise and restricted habitat
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requirements (McLean 1990). Indeed, invertebrates may be better indicators of the 'health' of a community than the plant species. The invertebrate fauna is a product of both plant community composition and vegetation structure. Therefore, changes in grazing pressure which result in alterations in canopy structure may affect the insect community long before changes in plant community composition are manifested (McLean 1990; Brown et al. 1990). Agri environment schemes (CS and ESA) provide a prescription / mechanism for the conservation, enhancement and restoration of chalk grassland. However, Scheme management prescriptions need to be of maximum ecological benefit to their target habitats. This project attempts to assess the effectiveness of management practices imposed through CS and ESA schemes by focusing on invertebrate communities. 2. Objectives The main objective of the project is to identify the factors which most effectively conserve and enhance the biological diversity of existing chalk grasslands or create new areas of such species-rich grassland on ex-arable land. In particular, the importance of site factors and management practices on plant and invertebrate diversity of chalk grasslands in the Environmentally Sensitive Areas or Countryside Stewardship Schemes will be identified. The results, in general, provide: . an assessment of the effectiveness of current management guidelines for chalk grassland in the Environmentally Sensitive Areas or Countryside Stewardship Schemes in achieving the conservation and enhancement of their plant and invertebrate diversity. . information allowing the modification and development of management guidelines for chalk grassland in these schemes. . site indicators which could be used to target funding for the discretionary Countryside Stewardship Scheme on those sites likely to maximise environmental improvement. There are five main scientific objectives of the project, corresponding to provisions in the ESA and Countryside Stewardship Schemes targeted at the conservation and enhancement of existing chalk grasslands, the restoration of abandoned chalk grasslands on which scrub has encroached and the recreation of chalk grassland on former arable land. 1. Identify the influence of site factors and management practices on the invertebrate diversity of existing chalk grassland sites of known botanical composition. 2. Assess the effectiveness of supplementary measures aimed at enhancing the colonisation of existing chalk grassland sites by plant and invertebrate species. 3. Study the development of plant and invertebrate communities of abandoned chalk grassland sites after the clearance of scrub. 4. Identify factors important in promoting the successful development of plant and invertebrate diversity of arable reversion sites. 5. Assess the effectiveness of supplementary measures in enhancing the colonisation of arable reversion sites by plants and invertebrates typical of unimproved chalk grassland. The aim was to identify factors that effectively conserve and enhance the biological diversity of chalk grasslands. In particular the relationships between site characteristics, management practices and invertebrate diversity are examined by taking two approaches, multisite comparisons and manipulative field experiments (Figure 1.). The approach involved a series of observational and experimental studies.
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Figure 1. The philosophy of the project, investigating the interrelationships of management, vegetation composition, diversity and structure and the consequences for the invertebrate communities on Chalk Grassland.
Site management (ESA / CS)
Vegetation: Vegetation: Composition and Structure diversity
Invertebrate: Abundance, composition and diversity 2. Methods and Materials Multisite Approach This consisted of a broadscale assessment of four grassland types, arable reversion, improved, semi- improved and unimproved (the target community of existing species rich chalk grassland) (examples are shown in Figure 2.). This monitoring work was carried out across sites in the South Downs ESA, South Wessex Downs ESA and CSS sites in the North and Berkshire Downs, the Chilterns and the Isle of Wight (Appendix 1 shows the geographical distribution of the sites). All ESA sites involved existing chalk grassland and its management (Appendix 4: Table A1) and these were surveyed in 1998 and 2000. The CSS sites were focused towards enhancement or recreation of chalk grassland (Appendix 4: Table A1) and were surveyed in 1999 and 2002. The scheduled 2001 monitoring programme of these sites could not proceed due to Foot and Mouth Disease quarantine measures. A total of 96 grassland and arable reversion sites were surveyed twice during the course of the project. At each site, the invertebrates and the vegetation were sampled three times, in late spring/ early summer, mid-summer and late summer/early autumn. A transect across the site, running through an established previously monitored ADAS botanical quadrat was taken and five equidistant sampling points chosen. Examples of grassland types and further details of all the sites are given in Appendix 2 and Appendix 3. A range of chalk grassland sites (U), semi-improved (SI), improved (I), and arable reversion (AR) sites were chosen using stratified-random selection of all the sites in the greater ADAS botanical monitoring scheme. This led to 96 sites being surveyed twice during the course of the project (NB: one improved CS site (NC4) was surveyed only in 1999 because it had been ploughed by the time of the second survey in 2002). The breakdown of the sites between the South Downs ESA, the South Wessex Downs ESA and the CSS sites was (with further details in Appendix 4 - Tables A1 and A2): 31 ESA sites in SD: 8U, 5SI, 9I, 9AR 23 ESA sites in SWD: 16U, 7I 38 CSS sites + four non-agreement sites (NC): 17U (+2NC), 7SI, 4I (+2NC), 10AR The regional distribution of the CSS sites is (Appendix 1, Appendix 4: Tables A1 and A2): 12 (+1NC) in Chilterns
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2 in SWD 4 (+2NC) on the Isle of Wight 20 in the North Downs Sampling design: Invertebrates were sampled on each site on five sampling plots along transects covering the length of the field. The transect was centred on an existing ADAS vegetation quadrat. If the size of the field allowed, the intersampling distance was 60 m, otherwise consistent but shorter distances between the plots were used to cover the length of the field or, in small sites, the transect was laid out in a “T”, “L” or “X” design. Sampling procedure:
Figure 2. Vortis suction sampler Invertebrates were sampled with a 'Vortis'-suction sampler being used in the South Downs (Figure 2). On each plot, 15 sampling intervals (duration of 10 ESA. Invertebrates are gently seconds each) were conducted within a radius of 3m around the shaken from the vegetation by a centre of the plot. Invertebrates were sampled three times a year, vortex of air before being sucked into the attached pot. early June, mid July and September on each site. ESA sites were sampled in 1998 and 2000; CSS sites were sampled in 1999 and 2002 (delay due to FMD). During each sample of each site, 10 samples of the vegetation height were taken randomly with a standardised 'drop-disk' (30cm diameter, 200g weight); in addition time, weather conditions (cloud cover, wind) and the current grazing regime were recorded. Additionally on 16 ESA (SD) sites (four sites each U, SI, I, AR) pitfall trapping with two traps set up 2m away from the centre of the plot in a rectangle to transect (10 traps per site). Traps were filled with common anti-freeze liquid (ethylenglycol) and left in the field for 14 days during June and October 2000. Traps were 10cm in diameter and 8.7 cm in depth. Soil cores from setting the pitfall traps were washed and sorted for invertebrates. The vegetation was surveyed in 2 x 2m quadrats over the centre of each sampling plot; ESA-sites in 1998, CSS-sites in 1999. The vegetation mapping was done twice on each site: first in June to map the occurrence of species, second in July using the domin-scale. Additional structure-pin-samples were taken on the CSS sites during the second sampling in July 2002 (15 pins per plot). The surrounding land use was recorded in 1998 and 1999 on OS 1:25,000 base map. Processing of samples: The invertebrates from the vortis and pitfall samples were live collected ('pooted'), sorted and transferred to tubes containing 70% IMS back in the laboratory. Samples were then sorted to order - Isopoda, Aranae, Coleoptera, Auchenorrhyncha, Heteroptera or Orthoptera. In addition, in 2002 the Hymenoptera, Diptera and snails (only sample 3) were recorded. The Isopoda, Coleoptera, Auchenorrhyncha, Heteroptera and Orthoptera were identified to species. Experimental Approach Two provisions were tested through manipulative replicated field experiments: Scrub clearance: There were three sites with scrub clearance: Brush Hill (Chilterns); Bacombe Hill (Chilterns); Whinless Downs (North Downs). At each site there was a mix of chalk grassland, scrub and areas where scrub had
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been cleared during the winter in different years. At Brush Hill there were 31 sampling plots: 5 chalk grassland, 14 scrub, 4 cleared in 1998/1999 and 8 cleared in 1997/1998. At Bacombe Hill there were 41 sampling plots: 5 chalk grassland, 4 scrub, 5 cleared in 1991/1992, 4 cleared in 1992/1993, 1 cleared in 1993/1994, 7 cleared in 1995/1996, 5 cleared in 1996/1997 and 10 cleared in 1997/1998. For Whinless Down there was 33 sampling plots: 12 chalk grassland, 12 scrub, 2 cleared in 1997/1998 and 7 cleared in 1998/1999. Hay spreading: Like the scrub clearance, there were three sites: Brush Hill (permanent pasture in the Chilterns); Cold Blow (1) (permanent pasture in the North Downs) and Cold Blow (2) (arable reversion). The effectiveness of the use of spreading hay from species rich areas of existing grassland gathered in the local vicinity to the experimental sites was assessed through factorial randomised block designed experiments with five replicates of each of four treatments: Hay spreading Cultivation Hay spreading + cultivation Control The grassland area at each site was divided into twenty 10 x 10m squares, arranged as 40 x 50m grid. Within each square, a randomly selected 5 x 5m plot was located and sampled. Hay was spread beginning of October 1998 (at Brush Hill) at a mass equivalent to 20 tonnes per hectare (recommended by FWAG), and was left in situ during the winter. Due to an unforeseen delay, hay was not spread at Cold Blow (both sites) until autumn 1999. The hay donor site for Brush Hill was Gomm's Wood, for Cold Blow (both sites) it was an adjacent SSSI. Soil samples (c. 1200 cm3) were taken randomly at Brush Hill around each treatment sub-plot to identify the plant species already present in the seedbank. Samples of hay were randomly taken from the centre of bales spread was sorted and any seed was identified/ counted. General methodology for both scrub and hay experiments: The invertebrates were sampled randomly from the 5 x 5m sub-plots with the vortis suction sampler and processed as described above. A pre-treatment sample was taken in July 1998. Likewise the vegetation structure was sampled by using a drop-disk as described above. Note that it was impossible to sample vegetation heights on overgrown scrub plots. The vegetation community was surveyed with 2 x 2m quadrats within the plots at the scrub sites (not possible in the overgrown scrubby plots) or by 1 x 1m quadrats in the sub-plots at the hay spreading sites. Vegetation quadrats were positioned over the centre of each plot/sub-plot and percentage cover recorded in 1999 and the domin-scale recorded in 2001. Additional structure-pin-samples were taken during the July invertebrate samples in 2001 and 2002. Fifteen pins were randomly recorded from each plot and, for consistency, samples were not taken from overgrown scrub plots. Statistical Analysis Multivariate analysis: Multivariate exploration techniques such as DCA and PCA revealed a large amount of noise in the overall dataset. This was a result of the large number of sites sampled over several years which gave rise to long species list with many species only represented in a few sites. The large number of zeros in the species x samples data matrix can lead to problems in multivariate techniques. Reduction of noise was achieved by splitting the dataset into separate sampling years and where appropriate land use categories. Furthermore, species data tables were transformed into Hellinger distances which overcomes the problems associated with many zeros/long gradients (horseshoe effect) and avoids the use of Canonical Correspondence Analysis (CCA) with its own inherent problems (overemphasising rare species) (Legendre & Gallagher 2001). After transformation the relationship between site factors, geographic location, management and
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vegetation communities, and their influence of invertebrate assemblages was determined by Redundancy Analysis (RDA) using CANOCO V4.5. Two main approaches were used centred around RDA where samples were standardised by the sample norm, i.e. the relative proportions of species are compared rather than absolute abundance. The first approach was designed to ascertain the relative importance of site factors, vegetation factors, grazing and geographic location on the overall dataset. This was done by variance partitioning using partial RDA which allows the proportion of variance explained by each component alone to be determined. The data was split into two sampling periods 1998/1999 and 2000/2002 with all CSS and ESA sites and land use classes included. The second approach was designed to get more detail about which factors are of greatest importance to invertebrate assemblages on chalk grassland. In this case RDA was applied to subsets of the data broken down into land use class, year of sampling and agri-environment scheme (ESA & CSS). For the unimproved sites CSS and ESA sites were treated independently. However, due to the low number of AR fields both CSS and ESA sites were combined and agri-environment scheme was included as and environmental variable. The forward selection (FS) process in CANOCO was used to produce a model based on site factors, NVC, geographic location, vegetation and grazing (and isolation for AR sites) which best explained the assemblages of Auchenorrhyncha and phytophagous beetles (Apionidae, Curculionidae, Chrysomelidae and Buprestidae) at different sites. When a dummy variable representing an environmental variable was selected during the FS process all the remaining dummy variables were also included in the final model. Overall significance of the model was given by a Monte Carlo permutation test on all canonical axes. Groups of Environmental variables used in variance partitioning and FS RDA for Unimproved sites. Variables in italics are dummy variables representing one environmental variable. Region (R) Vegetation (V) Site factors (S) Grazing (G) NVC South Downs Average height (VH) North Sheep CG2 SW Downs Height variance (HV) Aspect East Cattle CG3-5 North Downs Shannon-Wiener (S-W) (A) South Sheep + Cattle MG1 Chilterns No. Forbs/No. grasses West Other (e.g. MG5 (F/G) horses) Ungrazed MG6 Field size MG7 Additional Groups of Environmental variables used in FS RDA for AR sites. Isolation (nearest CG site) (I) Agri-Environment Scheme (AS) Adj (<200m) ESA Near (200-999m) CSS Far (>1000m) When appropriate, standard ANOVA, non-parametric tests, correlation and regressions were conducted. 3. Results and Discussion This project has produced incredible datasets on the invertebrates and vegetation that no single report can due justice to. For example, the total number of insects (from the selected insect orders) processed during this project is 473, 192, which includes, for example, 114 notable/rare beetle species (Appendix 5). There will be a series of scientific/technical papers produced from this work in addition to general articles and press releases. Each land-owner/farmer who participated will get an individual copy of the results/ species lists for their site. All such information will be also copied to DEFRA. As a summary, the main results are drawn out of the data here. The summary of the datasets/ results addresses the following points, all directly related to the overriding objectives of the project (see above). Essentially we ask “are the schemes working?” and to examine this we investigate, 1) Preserving/ conserving chalk grassland, and, 2) restoring and enhancing chalk grassland.
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1. Preservation/ conservation Chalk Grasslands are of high biodiversity and conservation interest and are included as a habitat in the UK BAP and EU Habitat Directive. Current Scheme management prescriptions have to be adequate to meet the commitments to the BAP/ Directive. Essentially, one of the main aims of Schemes has to be safeguarding lowland Chalk Grassland. Thus, by preserving the status quo, Schemes enhance the diversity of the countryside as a whole by preserving biodiverse habitat, and possibly (indirectly) conserving rare species. Although the two Schemes pre-date the Convention on Biol. Div., they are explicitly intended to contribute to the BAPs (Ovenden et al. 1998). The BAP focuses on safeguarding existing lowland CG with target 1 being to “arrest the loss” (restoration features only as target 6). Simply by examining the NVC characterisation of the sites we can indicate that the Schemes do indeed safeguard the habitat. Even sites that are not characterised as Unimproved (U) can be considered to be in the “Chalk Grassland community” (Rodwell 1992, p. 113). A simple example is the relationship between the NVC classification and the characterisation of the sites (e.g. U, SI, I, AR). In the variance partitioning tables (see later) NVC often explains slightly more variance in the data set than categorisation, e.g. for the Auchennorrenchya, NVC explains approximately 10% while categorisation explains 4%. Although there is autocorrelation between NVC and characterisation, some of the SI/ I sites can be classified as CG2 or CG3 NVC communities, thus within the Chalk Grassland community. Although there is no NVC equivalent for the invertebrates at present (this is an anticipated output of this project in the future), the communities include many habitat specialists, and form characteristic assemblages which reflect firstly the vegetation type (and thus management), and then regional (possibly ecophysiological) differences. The further analysis here concentrates on the biodiversity and assemblages of the invertebrates and vegetation from the ESA and CS Schemes and from the different land management Intensities (U, SI, I and AR). Comparison of Grasslands types (Management Intensities) The biggest differences are between the unimproved and improved grasslands and between the unimproved and arable reversion grasslands. Within all invertebrate taxa, species richness is significantly higher on the unimproved chalk grassland sites (Appendix: Results Table A3), with the only exception being the number of beetle species, which does not show significant differences between the unimproved and improved sites (Appendix: Results Table A3). The overall abundance of insects is significantly higher on the unimproved sites, but interestingly, for single Orders this difference is only reflected through the Heteroptera (True Bugs). For indicators, the number of typical chalk grassland and dry grassland leafhopper species is significantly higher and the number of nitrophilous species lower on the unimproved plots than on the improved and arable reversion sites. The number of notable species, generally dominated by beetles, is significantly higher on the unimproved sites in comparison with the improved and arable reversion sites (Appendix: Results Table A3). Although the vegetation diversity is significantly lower on the arable reversion sites compared with the improved sites (as expected), the invertebrate species numbers and abundances do not show differences between these two grasslands (Appendix: Results Table A3). The only exception is a significantly higher number of nitrophilous leafhopper species on the arable reversion sites. The overall number of insect species on the semi-improved grassland is even slightly higher than on the unimproved grassland due to high numbers of recorded beetle species. This results in significant differences of this grassland type to improved and arable reversion sites. The abundance of beetles and the number of typical chalk grassland leafhopper species is also significantly higher on the semi- improved grassland compared with the other two grassland varieties. The number of Heteroptera from the semi-improved grassland is also higher than on the arable reversion site.
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The trends reported above are consistent for ESA and CSS, as discussed in Fig. 3. Differences between the grassland types and management schemes in terms of invertebrate community composition and diversity are shown and discussed in Fig. 4. Comparison of vegetation height (structure / architecture) Vegetation height influences insect species richness greatly and, additionally, to some extent, the abundance of arthropods. The differences between the grassland and management types in terms of structure is shown and discussed in Fig. 5. All investigated invertebrate taxa show a highly significant increased number of species with increasing vegetation height (Appendix: Results Table A4) (Fig. 6). There is a trend for the number of specimens to increase with vegetation height, too. However, there are significant results for the number of Coleoptera and Auchenorrhyncha (Fig. 6). These relationships appear to be particularly strong on the Improved grasslands (Appendix 6). Interestingly, vegetation height does not seem to effect the number of rare notable species. Comparison of plant diversities The Heteroptera, Hemiptera as a whole, and the overall number of insect species increases with increasing plant diversity (alpha diversity according Shannon-Weaner) (Fig. 6). The abundance of Coleoptera, Heteroptera, typical chalk grassland and dry grassland leafhoppers and the richness of notable species also increase with increasing plant diversity (Appendix: Results Table A5). Figure 7 illustrates and discusses the effects of the different grassland types and management practices on the plant diversity/ species richness (number of plant species recorded. Comparison of plant species richness There is a positive correlation between the number of insect species within all investigated taxa and the number of plant species (Fig. 8). The number of typical chalk grassland insect species and dry grassland insect species increases as well with the number of plant species. Interestingly the number of rare notable insect species seems not to be affected by the number of plant species. The abundance of the Heteroptera and Coleoptera increases with plant species richness (Appendix: Results Table A6). The effects of the different grassland types and management practices on the plant diversity/ species richness (number of plant species recorded) is shown in Fig. 9.
2. Enhancement/ restoration (the effects of environmental factors, management and site location) Lowland grassland probably is the product, or even by-product, of agricultural practice rather than a fixed “community” (habitat/ecosystem) in the sense of e.g. primary rainforest. Indeed, on a global scale few communities exist which have not been impacted by agriculture to varying degrees. The grasslands of conservation interest have been and are being altered and lost due to continual changes in agricultural practice, with a consequent loss of biodiversity. ELMS include incentives to restore or recreate lowland chalk grassland if appropriate. The data collected from the multisite comparison enables an assessment of the importance of physical, management or vegetation features in the enhancement/restoration. Such information was supplemented with data from the experimental sites. However, there is a caveat: current management practices (and indeed site location) could be a traditional practice or, often more likely, it could be a modern prescription/plan that is based on pragmatic use of available resources. Species rich chalk grassland is the result of long-term (traditional) management practices, hence comparisons of recent management practices on the enhancement of chalk grassland biodiversity and conservation value may be mis-leading. Of great value though to practitioners is the ability, through projects and analyses such as those presented here and more detailed in the Appendices, to inform that a management practice happening “now” leads, or does not lead, to an assemblage of species very similar to others characterised as the chalk grassland community for conservation purposes.
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This second suite of results examines restoration and enhancement. Details are given below, but as above and throughout this report, further details and results are given in the appendices. Essentially, ESA and CSS enable semi-improved and improved grasslands to be recovered as chalk grasslands, as discussed previously, that arable reversion can lead to a successional trajectory resulting in a chalk grassland community. So, environmental/site factors, management practices (including a more detailed look at grazing), and the effects of supplementary methods (experimental site data) are examined below. [Continued p. 15]
Figure 3. The effects of ELMS on the species richness and abundance of inveretebrates. The example is taken from the Coleoptera, but all invertebrate groups examined show similar trends generally. However, the herbivorous leafhoppers (Auchenorrhyncha) had peak abundance on the CSS improved grasslands. This can be attributed to a nutrient signature and management interaction, the right type of vegetation with higher nutrients leading to greater invertebrate abundance. Data were pooled for all sampling occasions. U: Unimproved; SI: semi-improved; I: improved; AR: arable reversion.
ESA
Coleoptera richness Coleoptera abundance 40 200 30 150 20 100
10 50 Av.no. spp. 0 Av.numbers 0 U SI I AR U SI I AR
CSS
Coleoptera richness Coleoptera abundance 40 300 30 200 20
10 100 Av.numbers
Av.no. of spp. 0 0 U SI I AR U SI I AR
Auchenorrhyncha abundance 400 300 200 100
Av. numbers Av. 0 U SI I AR
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Figure 4. Differences in the insect assemblages, the Coleoptera is shown as an example but the trends are consistent between all groups investigated, due to different ELM Schemes and different grassland types. In all graphs, the X-axis represents differences in assemblages due to grassland type while the Y-axis represents differences due to geographic location of the sites. (A) The differences between the CS (yellow dots) and ESA (blue dots) Schemes. Here there is a distinct division between the two Schemes, which is probably due to geographic spread of the sites from east to west. With this combined dataset, the unimproved grasslands (U) had significantly different assemblages/ diversity of coleoptera that the semi-improved (SI or SIP), improved (I) or arable reversion (AR) sites. The order in terms of differences in assemblages/ diversities is U > SI > I and AR. (B) The differences between the four grassland types for the ESA scheme. Here there is a more distinct split with the AR sites having the worst beetle diversity/ assemblages, I sites are intermediate and the SI sites are not that different from the U sites. (C) The differences between the four grassland types for the CS scheme. Here the AR sites are similar in beetle diversity and assemblage to the SI and I sites. All three however, are different from the target U grasslands.
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ESA 12
8
4
Av.height (cm) 0 U SI I AR Figure 5. The effects of ELMS on the structure / architecture of CS the plant communities. ESA 12 and CSS are compared separately and then combined. 8 There is a diversity of structures for the Unimproved (U) and 4 Semi-improved (SI) grasslands while the arable reversion (AR) Av.height (cm) 0 and improved (I) grasslands U SI I AR show the signature of a fertility effect leading to greater structure (but less diverse). Both 12
8
4
Av.height (cm) 0 U SI I AR
Figure 6. The relationships between the invertebrate and plant communities in terms of structure and diversity. The leafhoppers (Auchenorrhyncha) are illustrated as an example. The other invertebrate groups show similar trends.
Auchenorrhyncha richness and sward height Auchenorrhyncha richness and vegetation richness
35 60 y = 0.3474x + 4.5888 30 50 R2 = 0.1653 25 40 20 30 15 20 y = 0.699x + 22.382
Height (cm) Height 10 R2 = 0.1441 10 5 Numberspecies of (plant) 0 0 0 10 20 30 40 0 10 20 30 40 Number of species (Auchenorrhyncha) Number of species
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Figure 7 The effects of ELMS on plant diversity. The number of plant species recorded was significantly different between the grassland types with arable reversion (AR) and improved (I) grasslands having fewer species than the semi-improved (SI) and the unimproved (U), as shown for the combined ESA and CSS data (Both). However, AR grasslands under CSS had significantly more species than AR under ESA, a reflection of the improved seed mixes that are allowable under the CSS regulations.
Both CS 40 40 30 30 20 20
10 10 Av.no. of spp. Av.no. of spp. 0 0 U SI I AR U SI I AR
[Continued from p. 11] Variance partitioning (NB: See Appendix 8 for the partitioning tables for 1998/1999 and 2000/2002) 1998 (ESA)/1999 (CSS) Survey Auchenorrhyncha: The location of the site (Region), the NVC botanical classification of the site and the interaction between all the Environmental Variables were significant in explaining the variability of the leafhopper dataset. Site factors, as defined above, were of marginal significance. Together, these environmental variables explained 67.7% of the variance within the leafhopper dataset for survey 1 (1998/1999). Phytophagous beetles : Every environmental variable was found to have a significant contribution in explaining the variability in the herbivorous coleoptera assemblages found. As with the leafhoppers, the most significant factors were region, NVC, site factors and the interaction of all variables. Heteroptera: Although the true bugs are often considered a variable group containing functionally different guilds of species (phytophages, omnivores and predators), the variance partitioning analysis conducted here illustrated some interesting patterns when compared with the beetles and leafhoppers. Only 8% of the total variability was explained by region and site factors (unlike the herbivorous beetles and leafhoppers previously), while the structure and composition of the vegetation assemblage accounted for 14.2%. 2000 (ESA)/2002 (CSS) Survey Auchenorrhyncha: The location of the site (Region), the NVC botanical classification of the site, the vegetation characterization and the interaction between all the Environmental Variables were significant in explaining the variability of the leafhopper dataset. Together, these environmental variables explained 73.6% of the variance within the leafhopper dataset for survey 2 (2000/2002). Grazing was not significant and did not contribute to determining the leafhopper assemblage for survey 2. Phytophagous beetles : Unlike Survey 1, not every environmental variable was found to have a significant contribution in explaining herbivorous coleoptera assemblages. Site factors and grazing had no affect on the assemblage. Together, the significant variables explained 60.7% of the variance within the phytophagous coleoptera for survey 2 (2000/2002). Heteroptera: Unlike Survey 1, all environmental variables except grazing was found to have a significant contribution in explaining true bug assemblages. Together, the significant variables explained 57.6% of the variance determining the assemblages for survey 2 (2000/2002).
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Effects of Environmental Factors (site, management, vegetation) Examples of the main effects are given here, all the multivariate analyses/ biplots for the invertebrate groups and factors are given in Appendix 9, which must be referred to in conjunction with this section. From these analyses, it is evident that all factors can have a significant impact on the indicator invertebrate assemblages, but not all invertebrates respond to all the factors and when they do respond they do not necessarily respond in the same direction (usually but not always). The vegetation in terms of site characterisation, NVC and structure all have importance in determining the invertebrate assemblage. Additionally there are grazing differences, particularly between stock type, but this requires further investigation (see Appendix 10). The analysis does not show if cattle, sheep or a mixture are preferable as a management tool trying to meet the Scheme aims (see also Appendix 10). NVC, vegetation height and grazing differences
0.8 Figure 8. 2000_02 Biplot of Auchenorrhyncha 19 Veg hei species richness from ESA unimproved sites. 18
15 Ungrazed 11 Open circles represent individual sites with larger 12 CG3-5 8 circles indicating high species richness. 18 19 22 Red circles illustrate the differences in NVC 17 5 20 Other East 13 MG5 4 classification, blue circles illustrate differences in Sh+Catt grazing (mixed is very different) and green represents West Sheep South North vegetation height. 18 Cattle CG2 For further details see Appendix 9, J and Appendix 16 10. 13 4 14 16 Variance in species assemblages explained by Axis 1 8
12 5 = 19.6% & Axis 2 =14.5 %. Model = VH+A+G
- explained 59.9% P<0.01. 0.8
-0.6 1.2
Aspect and grazing differences
0. 6 Sheep Figure 9. 1998-99 Biplot of phytophagous beetles from ESA unimproved sites. Red circles illustrate the differences in grazing (sheep are very different from the rest) and blue circles illustrate differences in site aspect (all aspects are different).
Aph euph Api walt Cas rubi Tim goet Sit wate Cry fulv Lon obli For further details see Appendix 9, A and Appendix
Cha hort Tra trog Cry bili 10. Cha conc Gym labi Lon fowl Api cine Aph herb South SD Tyc pici North Lon parv East Tyc line Api onop Man matt Api vire Sit lepi Variance in species assemblages explained by Axis 1 Api pisi Tra scro Apha pus Api tenu Mec pyra Rhi peri Api seni = 13.4% & Axis 2 = 10.5%. Model = R+A+G Tra alte
Api fulv Ungrazed SWD Tra aspe explained 44.6% P<0.01.
Oti lign Lon succ Ceu pall Sit hisp Ort seti Neo ferr Lon prat Api assi Api apri
West
Lon luri Neo tran Cattle Sit line
- 0. 4 -0.4 0.6
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Isolation effect
0.6 Figure 10. 2000_02 Biplot of phytophagous SWD beetles from AR sites. MG5 Chiltern Red circles illustrate the isolation factor with Lon succ adjacent sites having greatest diversity and Gym pascND Sph rubi Lon mela Hyp post MG6 Mec pyra abundance. Aph nigr Lon lyco Api gibb Psy chal Api fili Tri horr Hyp mele MG1 Api nigr Lon grac Sph test Lon flav For further details see Appendix9, N and Appendix Hyp venu Sit hisp Sit hume Api trif Phy robo Api fulv adj 11. Sit sulc Sit line Api assi far Tyc pici Api apri Phy viri Lon prat Sit lepi Api vire Lon luri Variance in species assemblages explained by Axis 1
near Tri trog = 18.2% & Axis 2 =12.4%. Model = R+I+NVC Aph euph Phy diad Phy undu Cha conc Api loti explained 64.7% P<0.01. MG7 Lon parv Neo ferr SD - 0.4
-0.6 0.6
It is interesting to note that environmental variables generally describe over 50% of the variance or drivers of the assemblages of the invertebrates (variance partitioning tables: Appendix 8). Indeed, even for “problematic” groups such as the Heteroptera (true bugs) with generally low numbers and varied feeding strategies, environmental variables describe over 30% of the total variability in the dataset.
Comparison of site size (area) Surprisingly, there seems to be no significant effect of the size / area of the site on the occurrence, abundance and diversity of chalk grassland arthropods at all, as shown in Appendix 6: Results Table A7.
Scrub clearance results The development of vegetation and invertebrate communities following scrub clearance is being assessed at three sites: Bacombe Hill (Bucks), Brush Hill (Bucks) and Whinless Down (Kent). Additionally, Bacombe Hill was the subject of an intensive survey of vegetation, soil seed bank and seed rain in 1998. At all three sites there were significant impacts of clearance and subsequent regeneration of the vegetation on the invertebrate community. Indeed some of the results are contradictory with different trends being observed at different sites. Although these can be attributed in part to time since clearance of the scrub being different at the different sites, there is a requirement for further research into the overall effects of scrub clearance on chalk grassland development. As the plant community establishes after clearance of the scrub and develops with time, a marked decrease in the number Coleoptera species (Fig. 11). It may well be that the plant species regenerating from the seed bank and colonising the site from neighbouring areas produce a sward of variable architecture and diversity. If the invertebrates were being driven primarily by sward architecture, as might be expected for more polyphagous herbivores for example, then as the grassland develops the architectural diversity will probably decrease thus restricting the number of niches for the invertebrates and lead to the reduction in abundance and diversity found. Support for this argument comes from the results from the scrub clearance site at Brush Hill. The Auchenorrhyncha, Coleoptera and Heteroptera (Fig. 12, 13 and 14) all increase in diversity (number of species) post scrub clearance, a trend also found at Whinless (Fig. 15 and 16).
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Coleoptera at Bacombe Auchenorrhyncha at Brush Hill y = -1.4043x + 20.543 y = 1.6146x + 3.1979 F1-94 = 49,85; P < 0.001 R2 = 0.3465 F + 11.61; P < 0.01 R2 = 0.2547 35 14 1-34 30 12
25 10 8 20 15 6 of species of of species of 4 No. No. 10
No. No. 2 5 0 0 0 1 2 3 4 0 2 4 6 8 10 Years since clearance Years since clearance
Figure 11. Decline in the number of Coleoptera Figure 12. Increase in the number of Auchenorrhyncha species recorded post scrub clearance. species recorded post scrub clearance.
Coleoptera at Brush Hill Heteroptera at Brush Hill y = 2.5104x + 10.677 y = 0.6771x + 6.0938 F1-34 = 4.82; P < 0.05 F1-34 = 15.35; P < 0.001 2 R2 = 0.3111 R = 0.1241 30 14 12 25 10 20 8 15 6
of species of
10 of species 4
No. No. 5 No. 2 0 0 0 1 2 3 4 0 1 2 3 4 Years since clearance Years since clearance
Figure 13. Increase in the number of Coleoptera Figure 14. Increase in the number of Heteroptera species recorded post scrub clearance. species recorded post scrub clearance.
y = 2.1471x + 14.265 y = 33.3 x + 68.4 2 Auchenorrhyncha at Whinless 2 Coleoptera at Whinless R = 0.1197 R = 0.26 F1-26 = 3.40, P = 0.07 F 1-26 = 8.84, P < 0.01 30 250
25 200
20 150 15 100
No. No. of species 10
of specimens (abundance) specimens of 50
5 No. No.
0 0 0 0.5 1 1.5 2 2.5 3 3.5 0 1 2 3 4 Years since clearance Years since clearance
Figure 15. Increase in the number of Coleoptera Figure 16. Increase in the number of Auchenorrhyncha species recorded post scrub clearance. individuals recorded post scrub clearance.
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Hay spreading results At Brush Hill there was an increase in forb diversity, and a decrease in the dominant coarse grasses, in the sward post hay spreading, leading to a positive effect on sward species richness (Fig. 17, Fig. 18). A result that is consistent with the other sites. The “new” species to the sward were consistent with those forb species found in the seed bank taken from the centre of hale bales of local provenance (Fig. 19). The increase in plant species richness would be expected, in general and with time, to result in a beneficial effect on the diversity of the invertebrates. Invertebrates were not introduced to the sites through hay bales (unlike plant seeds), as the very high temperatures inside a bale would generally act as a mortality factor. Additionally, due to the mobility of the invertebrates, particularly the predatory and polyphagous herbivore species, effects on species richness and abundance are more difficult to detect over a relatively short time. However, the total number beetle species recorded at Brush Hill indicates that even after only four years there is a distinct significant trend for species richness to be greater in plots post hay spreading (Fig. 20).
Botanical Diversity at Brush Hill Figure 17. Botanical diversity (species richness) at 30 b Brush Hill. b Different coloured bars represent different sampling years. 25 a a Treatments are, control, cultivation (cultiv.), hay spreading 20 1998 (hay) and the combination (hay+ cult.). 1999 15 2000 Different letter labels above bars indicate significant differences between treatments from an ANOVA 10 2001
No.plantspecies considering treatment as a main effect. The number of plant species recorded is significantly (p<0.05) greater in 5 plots where hay has been spread.
0 control cultiv. hay hay+cult. Treatment
Holcus lanatus at Brush Hill
60 a Figure 18. Percentage cover of Holcus lanatus at a 50 Brush Hill.
40 2001 Different colours represent different sampling years. 2000 Treatments as in Fig. 17. Bars labelled with different 30 b b 1999 letters indicate significant differences (ANOVA and 20 Tukey test).
% % coverage 1998 10 H. lanatus, a species typical of nutrient rich improved 0 grassland, becomes restricted (decrease in cover, p< control cultiv. hay hay+cult. 0.05) in treatments where hay was spread.
Treatment
Specific trends with the vegetation are shown in Appendix 12. Plant species associated with rich mesophylic of rich unimproved grasslands (e.g. Centaurea nigra, Galium mollugo, Euphrasia officinalis, Plantago lanceolata and Daucus carota; Appendix 12) colonise with hay spreading with time. Indeed the presence, albeit small, of some of these species in control plots in 2001 may indicate their spread from the
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hay spreading plots. Cultivation was also seen to have significant effects on the vegetation (Appendix 12). An important result, linking with BD 1437, is that cultivation leads to a significant reduction/eradication of creeping thistle, Cirsium arvense, although the low density and distribution of this species may be a compounding factor. Another negative effect of cultivation was on the spread of Trifolium repens (Appendix 12). Some species, however, benefit from cultivation; for example, Galium verum a typical chalk grassland and MG5 grassland plant seemingly benefits significantly from cultivation. This requires further investigation. The results for the invertebrates can be summarised as follows: Multivariate statistics showed mostly differences of the combination of hayspreading + cultivation to the other treatments, but varying from year to year and apparently not very strong. Brush Hill: No. of Coleoptera and overall insect species richness only positively influenced by treatments involving hay spreading (Fig. 20). Cold Blow AR: perhaps a negative effect of cultivation on insect species richness Cold Blow PP: Trends for increase of species richness of insects both by hay spreading and cultivation and even synergistic effect with combined treatment, but negative trend of cultivation on beetle abundance.
Figure 19. Seed abundance of forb species from samples taken from the middle of hay bales (of localFigure provenance) 1. Mean number prior of to seeds spreading of named at species Brush present Hill. per 50g (dry weight) sample (+/- se) taken from hay bales applied to Brush Hill (n=20)
200.0 180.0
160.0 140.0
120.0
100.0 hay 80.0
60.0 40.0
20.0
Mean no. of seeds per 50g (dry weight) weight) 50g(dry per seeds of no. Mean 0.0 Medi Dauc Orig Clin Trif Cent Gali Pimp Scab Lotu Leon Plan Linu Prun Lath Sene lupi caro vulg vulg spp. nigr veru saxi colu corn hisp lanc cath vulg prat jaco Forb species
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Brush Hill Grassland
100 Figure 20. Coleoptera diversity (species richness) at c 90 Brush Hill. b 80 a ab The total number of Coleoptera species recorded post hay 70 spreading. Treatments as in Fig. 17. Bars labelled with 60 different letters are significantly different (ANOVA and 50 Tukey test, p< 0.05). 40 30 There is a trend for more species to be recorded from
20 cultivated plots, significantly more from hay spread plots No. of Coleoptera species No. of Coleoptera 10 and the combined treatment. These results are probably 0 reflecting the trends in the vegetation, Fig. 17. control cultivated hay hay+cult Treatment
4. Summary / Discussion / Recommendations There are three key questions regarding the conservation, management and restoration/enhancement of chalk grasslands under the ELM Schemes; (1) are the schemes successful in the major aim of conserving the little chalk grassland that remains; (2) are the current management prescriptions and guidance on site location adequate (can a suitable site within a farm be identified and can it be effectively managed to restore/enhance chalk grassland); and (3) are the supplementary measures such as scrub clearance and hay spreading effective in accelerating/enabling chalk grassland restoration/enhancement? This report has pulled out and summarised some of the main results from this project, aiming to address these questions.
Conservation of existing chalk grasslands The ESA and CS schemes in their present form are a success in meeting the conservation of chalk grassland conservation as stipulated by the UK BAP and the EU Habitats Directive. Semi-improved and improved sites, when considered by the NVC, are CG2 or CG3, particularly if the sites are in the ESA scheme. Indeed, very few unimproved sites can be considered as poor conservationally. The NVC is an equally good if not better categorisation of the sites monitored than the site characterisation into unimproved, semi-improved, improved and arable reversion. For example, for the leafhoppers, the NVC explains approximately 10% of the variance while the characterisation explains approximately 4% (Variance partitioning tables for leafhoppers: Appendix 8).
Management/ site location The multisite comparison essentially addressed whether the ELM Scheme, particularly ESA and CSS were being effective in restoring chalk grassland and in managing what little chalk grassland remains (as unimproved grassland). The results have shown that there is a difference between the ESA and CS Schemes in achieving these goals, probably as a reflection of different management prescriptions. Additionally, the geographic location and therefore local climatic conditions (not to mention any complications that climate change may have – something that DEFRA, in relation to agri-environment schemes should examine urgently) affect the comparison. The geographic separation of the sites in this study affected the invertebrate diversity, structure and abundance. Although there were significant relation between plant diversity and structure with the invertebrate community, it was structure (architecture/ height) that was more important. Indeed, invertebrate diversity, abundance and structure were all greater when there was a greater diversity of vegetation structures. Agri-environment scheme
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policy needs to incorporate further measures to encourage stakeholders to manage for a variety of vegetation structures, whether it is through differential grazing or a more manipulative management programme. The ESA sites surveyed and compared in this study can be argued to be within a landscape that is characterised by Chalk Grassland (e.g. the South Downs) and are generally botanically species rich. The ESA prescriptions do not appear to be affecting this perception. However, the CSS sites are generally more conservation orientated or of a much smaller scale than the ESA sites. These sites are often characterised by rank tussocky grasslands that are diverse structurally but botanically not very exciting. However, such communities often support diverse rich invertebrate communities. It was the Arable Reversion sites which were the big difference between the ESA (particularly the South Downs) and CS Schemes. In the South Downs ESA, reversion occurred relatively early in the scheme and the sites were sown with ryegrass and clover dominated mixes (generally). Hence the developing sward was botanically and structurally poor thus being poor for the invertebrates and taking longer to start reverting to a sward similar to unimproved chalk grassland. In the CSS however, reversion occurred post 1992 and so the sites were sown with chalk grassland species (a mixture of forbs and grasses) (reflecting the change in policy). Hence, these sites were more botanically and structurally diverse, hence supporting a more diverse invertebrate community. These reversions were instantly closer to the rich “target communities” of unimproved chalk grassland.
Supplementary measures The use of tools such as scrub clearance and hay spreading clearly have advantages in helping farmers achieve the aims of the scheme. However, a lot more work needs to be done to aid policy revision in this area. For example, the perception that scrub is “bad” needs to be addressed; scrub enhances the botanical diversity and structure and so supports diverse invertebrate communities, so perhaps limited scrub is a good thing on sites. These general conclusions reflect those detailed in the Economic Evaluation of the CSS where there was a comparison of ESA vs. CSS. In this report, it was noted that the CSS focused on environmental improvement through policy directed by quality while the ESA had a clear focus on safeguarding the environment rather than paying farmers to improve the situation.
5. Recommendations (site location, management practices, supplementary measures 1. Grazing has a negative short-term effect on abundance and species richness of insects both on improved and unimproved grassland. Grazing is important however to reach the long term reduction of nutrients on improved grassland and arable reversion sites, and to keep scrub encroachment on unimproved grasslands to a minimum. Grazing should not be seen as a short term management option. 2. Whether cattle, sheep or a mixed stock is most effective cannot be advised from our results. This is a fundamental point and grazing is a very important management tool and so further research is required to address this anomaly (See Appendix 10). 3. DEFRA has to be very committed over a very long period to subsidise extensive farming on improved grassland sites and to enable arable reversion to be fully effective. Not one single site, out of those monitored, resembles unimproved grassland, so far, neither in the composition of vegetation nor invertebrate communities. Although sites are progressing towards the chalk grassland community. 4. DEFRA have to fund truly long term research to, for example, monitor the success of grassland restoration with its specific management guidelines.
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5. If the purpose of arable reversion is to create intact chalk grassland, it should concentrate on sites located on slopes or hilltops and exclude sites at valley bottoms. The reason is that it is very difficult to reduce the amount of nutrient on flat valley sites. Indeed, there is probably a flow of nutrients (eutrophication) from the surrounding slopes onto such flat site. Arable reversion on hilltops and slopes on the other hand may prevent further enrichment of adjacent intact grassland. Arable reversion and extensification of improved grassland in a valley bottom may lead eventually to species rich mesotrophic grassland, which itself is an endangered habitat. Obviously further research is needed here and advice will need to be given to farmers in deciding the best location for arable reversion on individual farms. 6. Sites for restoration/enhancement need to be adjacent or in the close proximity to an existing chalk grassland (unimproved) patch/site. However, it is still recommended to establish new chalk grassland in isolated locations to provide stepping stones for the exchange of organisms between established intact grassland habitats. This is a worthy goal in itself but the isolation equation needs to be considered from both sides; further research is needed to examine site isolation. 7. When recording communities, species richness / diversity are useful ecological measures that are relatively simple to understand. However, in examining indicators of chalk grassland it is apparent that some of the rare leafhoppers are found in species poor vegetation assemblages, often of short swards. The development of invertebrate indicators has been started by this project but does need further research. 8. The importance of sward structure as a driver of invertebrate diversity is becoming a strong message from this and other DEFRA BD14 projects. Future work examining the importance of variability in sward structure in relation to botanic diversity as factors promoting invertebrate diversity is strongly recommended. This work was initiated in this project. Farmers need to be encouraged to be flexible in their grazing regimes to try and achieve a mosaic of structures on farms/ fields. 9. Landscape conservation, environmental change and agri-environment schemes: BD1414 examined a large number of sites and assessed their biodiversity in relation to prescriptions for CS and ESA. The data could be examined in terms of the importance of agri-environment schemes in relation to wider conservation issues. There is a sense of the need for a “joined-up” landscape from the conservation agencies, the role of agriculture in this would be essential. The results from this project could be re-examined in a desk-top scoping study looking at these issues of concern (for example, particularly in relation to the outputs of the MONARCH and REGIS projects which examined impacts of climate change on UK biodiversity).
7. Acknowledgements This project started in 1997 and has seen a number of staff changes. Significant contributions to the development, establishment, running, analysis and invertebrate taxonomy have been made by Prof. V.K. Brown, Simon Mortimer, Andrea Turner, Steph. Harris, Alex Brook, Tom Ings, Norbert Maczey, Angi Toller, John Hollier and Roger Booth.
8. References Anon (1997) Environmental Monitoring in the South Wessex Downs ESA 1993-1996. ADAS Report to the Ministry of Agriculture, Fisheries and Food. Anon (1996) Botanical Monitoring of Grassland in the South Downs ESA 1987-1995. ADAS Report to the Ministry of Agriculture, Fisheries and Food. Anon (1995) Biodiversity: the UK Steering Group Report. HMSO, London. Blackwood, J.V. & Tubbs, C.R (1970) A quantitative survey of chalk grassland in England. Biological Conservation, 3, 1-5.
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Brown, V.K., Gibson, C.W.D. & Sterling, P.H. (1990) The mechanisms controlling insect diversity in calcareous grasslands. Calcareous Grasslands - Ecology and Management (eds S.H. Hillier, D.W.H. Walton & D.A. Wells), pp. 79-87. Bluntisham Books, Huntingdon. Graham, D.J. & Hutchings, M.J. (1988a) Estimation of the seed bank of a chalk grassland ley established on former arable land. Journal of Applied Ecology, 25, 241-252. Graham, D.J. & Hutchings, M.J. (1988b) A field investigation of germination from the seed bank of a chalk grassland ley on former arable land. Journal of Applied Ecology, 25, 253-263. Gibson, C.W.D. & Brown, V.K. (1992) Grazing and vegetation change: deflected or modified succession? Journal of Applied Ecology, 29, 120-131. Gibson, C.W.D. & Brown, V.K. (1991) The nature and rate of development of calcareous grassland in southern Britain. Biological Conservation, 58, 297-316. Gibson, C.W.D., Watt, T.A. & Brown, V.K. (1987) The use of sheep grazing to recreate species-rich grassland from abandoned arable land. Biological Conservation, 42, 165-183. Hutchings, M.J. & Booth, K.D. (1996) Studies on the feasibility of re-creating chalk grassland on ex-arable land. I. The potential role of the seed bank and the seed rain. Journal of Applied Ecology, 33, 1171-1181. Jefferson, R.J. & Robertson, H.J. (1994) Lowland grassland. Habitat Conservation in England (ed. A.M. Moffatt), pp. 88- 139. English Nature Research Report No. 96. English Nature, Peterborough. Keymer, R.J. & Leach, S.J. (1990) Calcareous grassland - a limited resource in Britain. Calcareous Grasslands - Ecology and Management (eds S.H. Hillier, D.W.H. Walton & D.A. Wells), pp. 11-17. Bluntisham Books, Huntingdon. Kirby, P. (1992) Habitat Management for Invertebrates: a Practical Handbook. RSPB, Sandy. Legendre, P. and E. Gallagher (2001). Ecologically meaningful transformations for ordination of species data. Oecologia, 129: 271-280. McLean, I.F.G. (1990) The fauna of calcareous grasslands. Calcareous Grasslands - Ecology and Management (eds S.H. Hillier, D.W.H. Walton & D.A. Wells), pp. 41-46. Bluntisham Books, Huntingdon. Newbold, C. (1989). Semi-natural habitats or habitat recreation: conflict or partnership? In Biological Habitat Reconstuction (G.P. Buckley, ed.), pp. 9-17. London: Belhaven Ovenden, G.N. Swash, A.R.H. & Smallshire D. (1998). Agri-environment schemes and their contribution to the conservation of biodiversity in England. Journal of Applied Ecology, 35: 955–960. Rodwell, J.S. (1992). British Plant Communities. Vol. 3 Grasslands and Montane Communities. Cambridge University Press. Smith, C.J. (1980) The Ecology of the English Chalk. Academic Press, London. Wells, T.C.E. (1983) The creation of species-rich grasslands. Conservation in Practice (eds A. Warren & F.B. Goldsmith), pp. 215-232. Wiley, Chichester. Wells, T.C.E. (1991) Restoring and re-creating species-rich lowland dry grassland. The Conservation of Lowland Dry Grassland Birds in Europe (eds P.D. Goriup, L.A. Batten & J.A. Norton), pp. 125-132. Joint Nature Conservancy Council, Peterborough. Wells, T.C.E., Bell, S.A. & Frost, A. (1981) Creating Native Grasslands using Native Plant Species. Nature Conservancy Council, Shrewsbury. Wilson, P.J. (1992) The natural regeneration of vegetation under set-aside in southern England. Set-Aside (ed. J. Clarke), pp. 73-78. British Crop Protection Council, Farnham, Surrey.
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APPENDICES
Appendix 1. Geographic location of the sites. Yellow dots indicate Unimproved; orange dots indicate Semi-improved and Improved and red dots indicate Arable Reversion sites.
Appendix 2. Examples of the four grassland types investigated during this project. Differences in structure and biological diversity are apparent from the photographs.
Unimproved Semi-improved
Improved Arable Reversion
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Appendix 3: SITE DESCRIPTIONS
Environmentally Sensitive Area Scheme Sites South Downs Site 100 (Grid reference: TQ22073): This is an 11ha, unimproved field on a south-west facing slope in West Sussex, situated just north of the A27 near Shoreham-by-sea. The vegetation comprises a mosaic of grass/forb sward of variable height interspersed with scrub, classified as MG1 at point A of the sampling transect and CG3b at points B-E. Site 101 (Grid reference: TQ314134): This is a 13ha, unimproved field on a north-west facing slope, lying on the West/East Sussex border, north of Brighton and west of the A23. The transect lies between two archaeological mounds and has been classified as CG2b. Site 102 (Grid reference: TQ 277113): This is a 1ha, unimproved field on a south-west facing slope in West Sussex, east of the village of Saddlescombe and adjacent the Sussex Border Path. The vegetation comprises a short sward with occasional patches of scrub, classified as CG3d along the sampling transect. Site 110 (Grid reference: TQ 174073): This is a 9ha, unimproved field on a north-east facing slope in West Sussex, situated north of Worthing and just north of the A27. The vegetation comprises a medium height sward and is classified as CG5a along the sampling transect. The field lies directly above an arable field in the valley bottom. Site 111 (Grid reference: TQ 189087): This is an 18ha, unimproved field on a north-west facing slope in West Sussex, situated south of the small town of Steyning and west of the River Adur. The vegetation comprises a short-medium height sward, classified as CG4c, surrounded by shrubs and large patches of Urtica spp. on the upper slope and a dirt track in the valley immediately below the site. Site 112 (Grid reference: TQ 335131): This is a 16ha, unimproved field on a north-east facing slope in East Sussex, situated on the northern edge of a Nature Reserve and south of the village of Westmeston. The transect vegetation is classified as CG2a and the area has numerous archaeological sites (tumuli, mounds and field systems) suggesting some protection from disturbance. Site 117 (Grid reference: TQ 454062): This is a 49ha, unimproved field on a north-east facing slope in East Sussex, situated north of Newhaven on Beddingham Hill, just north of the South Downs Way. The transect vegetation is classified as CG5a along the sampling transect, and the area has a number of archaeological sites (tumuli, mounds and settlements) suggesting some protection from disturbance. Site 303 lies in the same field. Site 119 (Grid reference: TV 569967): This is a 24ha, unimproved field on a north-east facing slope in East Sussex, situated south-east of Friston near the Sheep Centre and below a tumulus. The vegetation comprises a medium height sward and is classified as CG2c along the sampling transect. Site 210 (Grid reference: TQ 166113):
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This is a 10ha, semi-improved field on a gently sloping, north-east facing slope in West Sussex, situated on the eastern fringe of Steyning with woodland to the west. The vegetation comprises a short, patchy sward and is classified as CG2c along the sampling transect. Site 211 (Grid reference: TQ 392063): This is a 10ha, semi-improved field on a south-east facing slope in East Sussex, situated east of Brighton and accessible only by a bridleway or footpaths. The site is surrounded by arable farmland and has been classified as MG6a along the sampling transect. Site 215 (Grid reference: TQ 413052): This is a 5.5ha, semi-improved field on a south facing slope in East Sussex, situated east of Brighton adjacent a small village called Rodmell but accessible only by bridleway or track. The site is surrounded by farmland, mainly arable and improved, and has been classified as MG5b along the sampling transect. Site 216 (Grid reference: TQ 477019): This is a 9.5ha, semi-improved field on a north-west facing slope in East Sussex, situated north of Seaford. The vegetation comprises a short, tussocky sward, classified CG2c along the sampling transect, with scrub lining the upper part of the slope. Site 217 (Grid reference: TQ 513029): This is a 7ha, semi-improved field on a south facing slope in East Sussex, situated on the western fringe of Alfriston. The vegetation comprises a short, patchy sward, classified as CG2c along the sampling transect, with scrub along the western side of the site. Site 300 (Grid reference: TQ 170083): This is a 15ha, improved field on a north-west facing slope in West Sussex, situated north of Worthing and accessed from the village of Coombes by footpath. The vegetation comprises a short, patchy sward, classified as MG6c along the sampling transect, and the site is surrounded by farmland. Site 301 (Grid reference: TQ 187082): This is a 15ha, improved field lying in an east facing valley in West Sussex, situated north of Worthing and accessed from the village of Coombes by footpath. The vegetation comprises a short, patchy sward, classified as MG7a along the sampling transect, and the site is surrounded by farmland. Site 302 (Grid reference: TQ 294130): This is a 13ha, improved field on a south-east facing slope in West Sussex, situated in the fork of the A23 and A273 north of Brighton. The vegetation has been classified as MG7a along the sampling transect, and the surrounding area includes farmland and a rifle range. Site 303 (Grid reference: TQ 456065): This is a 49ha, improved field lying in a north facing valley in East Sussex, situated north of Newhaven on Beddingham Hill, just north of the South Downs Way. The transect vegetation is classified as MG6c along the sampling transect, and the area has a number of archaeological sites (tumuli, mounds and settlements) suggesting some protection from disturbance. Site 117 lies in the same field. Site 312 (Grid reference: TQ 393054): This is a 5.5ha, improved field on an east facing slope in East Sussex, situated east of Brighton and accessible only by a bridleway and footpath. The site is surrounded by arable farmland and has been classified as MG6a along the sampling transect. Site 314 (Grid reference: TQ 412043):
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This is a 21.5ha, improved field on a north-west facing slope in East Sussex, situated east of Brighton near the small village of Telscombe. The site is surrounded by farmland, mainly arable and improved, and has been classified as MG5b along the sampling transect. Site 317 (Grid reference: TV 570970): This is a 5.5ha, improved field on a south-west facing slope in East Sussex, situated south-east of Friston near the Sheep Centre. The vegetation comprises a short sward, classified as MG6c along the sampling transect, and the upper edge of the site is flanked with scrub. Site 318 (Grid reference: TV 571983): This is an 11.5ha, improved field on a north-west facing slope in East Sussex, situated on the eastern fringe of Friston. The vegetation comprises a variable height sward, classified as MG6c along the sampling transect, with patches of Urtica spp. Site 319 (Grid reference: TV 574967): This is a 24ha, improved field on a north-west facing slope in East Sussex, situated east of Friston near the Sheep Centre. The vegetation comprises a short-medium height sward, classified as MG6 along the sampling transect, and the site is edged by scrub. Site 710 (Grid reference: TQ 146074): This is a 6ha, arable reversion field on a south facing slope in West Sussex, situated north of Worthing adjacent a golf course, Cissbury Ring and ancient flint mines. The vegetation has been classified as MG7b along the sampling transect. Site 711 (Grid reference: TQ 163088): This is a 7.5ha, arable reversion field on a south-west facing slope in West Sussex, situated north of Worthing approximately 1.5 miles north-east of site 710 on the edge of the South Downs Way. The vegetation comprises a fairly uniform sward, which has been classified as MG7b along the sampling transect. Site 712 (Grid reference: TQ 183084): This is a 17ha, arable reversion field on a north-east facing slope in West Sussex, situated west of Coombes and the River Adur. The vegetation comprises a short-medium sward, interspersed with small patches of Cirsium spp, and classified as MG7b along the sampling transect. Site 713 (Grid reference: TQ 185069): This is a 23.5ha, arable reversion field on a north-east facing slope in West Sussex, situated just north of Lancing and approximately 1 mile due south of site 712. The vegetation has been classified as MG7b along the sampling transect. Site 715 (Grid reference: TQ 465058): This is a 12ha, arable reversion field on a south facing slope in East Sussex, situated north-east of Newhavern and adjacent Males Burgh tumulus on the South Downs Way. The vegetation has been classified as MG7b along the sampling transect. Site 716 (Grid reference: TQ 472058): This is a 11.6ha, arable reversion field on a south facing slope in East Sussex, situated north-east of Newhavern to the right of site 715. There are a number of tumuli and Long Barrows in the area and a plantation just north of the field. The vegetation has been classified as MG7b along the sampling transect.
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Site 717 (Grid reference: TQ 508029): This is a 16ha, arable reversion field on a south-east facing slope in East Sussex, situated on the western fringe of Alfriston and accessible only by by-way and footpath. The vegetation comprises a short- medium height sward, with occasional Cirsium patches, and has been classified as MG5a along the sampling transect. Site 718 (Grid reference: TV 511978): This is an 8ha, arable reversion field on an east facing slope in East Sussex, situated on the coast to the east of Seaford at the mouth of the Cuckmere River, on the other side of which lies Seven Sisters Country Park. The vegetation comprises a tall, fairly uniform sward and has been classified as MG7a along the sampling transect. Site 719 (Grid reference: TQ 575009): This is a 5ha, arable reversion field on a west facing slope in East Sussex, situated on the western fringe of Eastbourne. A belt of woodland separates the town and the site, which lies on the edge of the South Downs Way in an area of tumuli and ancient field systems. The vegetation comprises a tall, fairly uniform sward with occasional scrub patches has been classified as MG7a along the sampling transect.
South Wessex Downs Site 2 (Grid reference: ST 829335): This is a 70.5ha, unimproved field on a south-east facing slope in Wiltshire, just north of Mere. The site lies in one of a series of narrow side valleys (Ashfield Bottom) with a strip of woodland joining the head of Ashfield Bottom to its neighbouring valley. All the valleys have well preserved examples of Strip Lynchets. The vegetation is of variable height with occasional patches of scrub, and has been classified as CG2a along the sampling transect. Site 3 (Grid reference: ST 955213): This is a 24.5ha, unimproved field on an east facing slope in Wiltshire, south-east of the small village of Berwick St John. The site lies on a steep slope with woodland on the slope to the north and on the opposing slope. The vegetation has been classified as CG2b along the sampling transect. Site 6 (Grid reference: ST 972363): This is an 8.5ha, unimproved field on a north facing slope in Wiltshire, south of the village of Stockton near Warminster. The transect lies on a slope topped by earthworks. The vegetation comprises a short sward, classified as CG2c along the sampling transect, with occasional patches of scrub and Cirsium spp, and some ant hills. Site 8 (Grid reference: ST 919204): This is a 7ha, improved field on a north-west facing slope in Wiltshire, south-east of Shaftesbury. The site lies adjacent a Roman Road and Ox Drove track, along which there are a number of archaeological features such as tumuli and earthworks. The vegetation has been classified as MG6a along the sampling transect. Site 9 (Grid reference: ST 803345): This is an 18ha, unimproved field on a south-west facing slope in Wiltshire, just north of Mere. The site lies above a small plantation and beneath a set of earthworks and a covered reservoir. The vegetation
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comprises a short sward with occasional patches of scrub and has been classified as CG2b along the sampling transect. Site 10 (Grid reference: ST 920207): This is a 37ha, unimproved field on a steep, north-east facing valley slope in Wiltshire, south-east of Shaftesbury. The site lies adjacent a Roman Road and the Ox drove track, along which there are a number of archaeological features such as tumuli and earthworks. The vegetation comprises a short- medium, fairly uniform sward, classified as CG2c along the sampling transect, with a thin belt of woodland along the lower edge of the site. Site 12 (Grid reference: ST 811354): This is a 28.5ha, improved field on a south facing slope in Wiltshire, just north of Mere in a complex valley system accessible only by Ox Drove track and foot. The area has numerous archaeological features such as tumuli and earthworks. The vegetation has been classified as CG2c along the sampling transect. Site 13 (Grid reference: ST 898208): This is a 13.5ha, unimproved field on a steep, north facing valley slope in Wiltshire, south-east of Shaftesbury and north of Melbury Wood. The site lies adjacent the Ox Drove track and is surrounded by tumuli. The vegetation comprises a short-medium, fairly uniform sward with occasional livestock scrapes and has been classified as CG2c along the sampling transect. Site 14 (Grid reference: SU 003259): This is a 12ha, improved field on a south facing slope in Wiltshire, south-west of Salisbury in a shallow valley on Fifield Down, just west of the small village of Broad Chalke. The site lies in a shallow, curving valley with broken belts of scrub along the upper slopes. The vegetation comprises a short, fairly uniform sward dotted with Cirsium, which has been classified as CG2b along the sampling transect. Site 15 (Grid reference: SU 012251): This is a 15ha, unimproved field on a south-west facing slope in Wiltshire, east of Shaftesbury on the fringe of the small village of Fifield Bavant. The site lies in an area of mainly arable farmland interspersed with a few small patches of woodland. The vegetation comprises a short, fairly uniform sward with occasional livestock scrapes and has been classified as CG3c along the sampling transect. Site 17 (Grid reference: ST 823368): This is a 14.5ha, unimproved field on a north facing slope in Wiltshire, east of Kingston Deverill and above the River Wylye. The site lies immediately above a belt of woodland (Truncombe Wood) and in an area of archaeological features such as tumuli and earthworks. The vegetation comprises a tussocky sward, dotted with Cirsium, and has been classified as CG2c along the sampling transect. Site 18 (Grid reference: ST 909207): This is a 4.5ha, improved field on a steep, north-east facing slope in Wiltshire, south of the village of Ludwell near Shaftesbury. Farmland, arable and pasture, lies at the foot of the slope and there are patches of woodland on surrounding slopes. The vegetation comprises a fairly uniform sward classified as MG7a along the sampling transect. Site 20 (Grid reference: SU 111247): This is a 12ha, unimproved field on a west facing slope in Wiltshire, south of Coombe Bissett near Salisbury. The site is edged by scrub patches, and the vegetation comprises a fairly uniform, medium to tall sward classified as CG2c along the sampling transect.
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Site 22 (Grid reference: SU034263): This is a 22ha, improved field on a south-west facing slope in Wiltshire, on the outskirts of Broad Chalke, south-west of Salisbury. The site is covered with old and new scrub patches, including along the sampling transect where the tall sward has been classified as MG1. Site 23 (Grid reference: SU 034272): This is a 12.5ha, improved field on a west facing slope in Wiltshire, just north of Broad Chalke, and south-west of Salisbury. The transect lies in a shallow valley beneath a belt of woodland. The vegetation comprises a tall, fairly uniform sward classified as MG5b along the sampling transect. Site 27 (Grid reference: SU 024268): This is an 11.5ha, improved field on a north-east facing slope in Wiltshire, on the edge of Knapp Down just north of Broad Chalke. A belt of woodland lies adjacent the field and patches of Urtica are dotted across its slope. The vegetation comprises short sward classified as MG5b along the sampling transect. Site 28 (Grid reference: ST 800047): This is a 24.5ha, unimproved field on a south facing slope in Dorset, east of Winterborne Houghton in a valley mostly surrounded by woodland. The vegetation comprises a short sward, classified as CG2b along the sampling transect, with occasional livestock scrapes and patches of Cirsium. Site 29 (Grid reference: ST 998267): This is a 12ha, unimproved field on a steep, west facing slope in Wiltshire, south of the village of Fovant and accessible only by byway and foot. The transect lies below a narrow belt of trees and the valley floor below the site is used for farmland. The vegetation has been classified as CG2c along the sampling transect. Site 30 (Grid reference: ST 949242): This site comprises two unimproved fields of 14ha each, on a steep, south-east facing slope in Wiltshire, north of the village of Berwick St John and accessible only by byway and foot. The transect skirts an area of scrub in one field and the vegetation has been classified as CG2a along the sampling transect. Site 31 (Grid reference: ST 880176): This is a 3.5ha, unimproved field on a south-east facing slope in Dorset, and is part of Fontmell Down SSSI owned by the National Trust. There is an extensive area of woodland running south east from the SSSI. The vegetation comprises a short-medium height sward, classified as CG2a along the sampling transect, and there are patches of scrub edging the site. Site 35 (Grid reference: SU 061239): This is a 3.5ha, unimproved field on a north facing slope in Wiltshire, south-west of the village of Broad Chalke. The site lies in a shallow valley in which there are well preserved archaeological features of a field system and an enclosure. The vegetation comprises a medium height sward, classified as CG2b along the sampling transect, and there are patches of scrub around the site. Site 38 (Grid reference: SY 639999): This is an 8ha, unimproved field on a west facing slope in Dorset, on the fringe of the village of Sydling St Nicholas and immediately below a tumuli. The site is surrounded with belts of scrub and hedges of trees and shrubs. The vegetation comprises a short sward, classified as CG2a along the sampling transect, and there are patches of exposed chalk. Site 40 (Grid reference: ST 809088):
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This is an 11.5ha, unimproved field on a south-east facing slope in Dorset, on Turnworth Down between the small village of Belchalwell Street and Blandford Forest. The transect lies amongst scrub and trees, and the vegetation comprises a tall sward, classified as MG5b along the sampling transect.
Countryside Stewardship Scheme Sites Site C1 (Grid reference: TL098244): This is a 6ha, unimproved site of common land on the eastern edge of Luton, in Bedfordshire. The site lies on a westerly slope with evidence of Strip Lynchets running north – south, and is surrounded by residential buildings, playing fields and some farmland. There is heavy scrub invasion across the site, meaning the vegetation along the transect, which has been classified as CG2c, is extremely variable both in height and composition. Site C2 (Grid reference: TL007209): This is a 2.5ha, unimproved flat site on the top of Dunstable Down, in Bedfordshire. Land use around and on the Downs includes residential, a gliding club and a golf course. The site itself is in an area of trees, scrub and chalk grassland. The transect straddles a fence so that sample points D and E lie in a more frequently traversed, short sward area adjacent a shallow dry ditch, and the remaining three points lie in a narrow strip of cleared, but rapidly re-invading scrub. The vegetation has been given a general classification of CG3b along the transect. Site C3 (Grid reference: TL006211): This is a 12.5ha, unimproved site on the top of Dunstable Down, in Bedfordshire, situated close to site C2. This is a cross-shaped transect, with sampling points close to the entrance gate, between and either side of two tumuli, and a final sampling point down-slope towards the gliding site. A footpath dissects the transect. The vegetation comprises a variable sward and has been classified as CG3b along the sampling transect. Site C4 (Grid reference: SP959168): This is a 19ha, unimproved site on a south facing slope in Buckinghamshire, east of Ivinghoe. The site is on Beacon Hill, one of the Ivinghoe Hills, and is owned by the National Trust. The Ridgeway Path runs close to the transect and there are several tumuli in the vicinity. The vegetation comprises a variable sward with some scrub re-growth, and has been classified as CG3a along the sampling transect. Site C5 (Grid reference: SP960157): This is a 12ha, unimproved site on a steep, south facing valley slope in Buckinghamshire, east of Ivinghoe. Situated on Steps Hill, the site lies in a valley, accessible only by foot, which is dotted with Crataegus trees in the bottom. The vegetation comprises a medium to tall sward and has been classified as CG2a along the sampling transect. Site C6 (Grid reference: SP961154): This is a 4ha, improved field on a gentle, south-west facing slope in Buckinghamshire, east of Ivinghoe. The site is part of National Trust land and can be reached from the road by the Icknield Way Path. It is edged by woodland on two sides and is situated adjacent a small, deep valley of intact chalk grassland. The vegetation comprises a medium height, fairly uniform sward, classified as CG3d along the sampling transect.
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Site C7 (Grid reference: SP917035): This is a 3ha, arable reversion field on a south facing slope in Buckinghamshire, on the outskirts of Ballinger Common north of Amersham. The lower part of the site is edged by woodland and the vegetation comprises a tall sward, classified as MG6a along the sampling transect. Site C8 (Grid reference: SP918033): This is a 3ha, semi-improved field on a north facing slope in Buckinghamshire, on the outskirts of Ballinger Common north of Amersham. The site is surrounded by woodland and tree belts, and the vegetation comprises a tall sward, classified as MG6a along the sampling transect. Site C9 (Grid reference: SU919904): This is a 2.5ha, unimproved site on a north-west facing slope in Buckinghamshire, on the outskirts of Beaconsfield. The area below the site is a disused industrial wasteground, now much overgrown, whilst at the upper end, a belt of woodland separates a residential area from the site. The vegetation, comprising a patchy sward with some scrub re-growth, has been classified as CG3b along the sampling transect. Site C10 (Grid reference: SU572815): This is a 10.5ha, arable reversion field at the base of a slope in Berkshire, on the outskirts of Goring, south of Oxford. The site lies adjacent an old ridgeway and field system, amongst farmland. A belt of trees runs along the field edge and the vegetation comprises a short to medium sward, classified as MG6a along the sampling transect. Site C11 (Grid reference: SU572818): This is an 11.5ha, semi-improved field on a south-west facing slope in Berkshire, on the outskirts of Goring, south of Oxford, on the hill above site C10. The vegetation comprises a short to medium sward, classified as MG6a along the sampling transect. Site C12 (Grid reference: SU633757): This is a 10.5ha, flat, arable reversion field in Berkshire, on the outskirts of Pangbourne. It is a single, privately-owned field, managed with much enthusiasm by the owner to restore wildflowers. The site is edged with trees, mostly planted and including fruit trees, and incorporates a purpose-built pond and waterfall. The vegetation comprises a variable height sward, classified as MG5b along the sampling transect. Site C13 (Grid reference: SU371293): This is a 14ha, arable reversion field on a west facing slope in Hampshire, on the edge of the small village of Kings Somborne, west of Winchester. The site is surrounded by farmland, mostly arable, and woodland. The vegetation comprises a fairly uniform sward, classified as MG6a along the sampling transect. Site C14 (Grid reference: SU378290): This is a 4ha, semi-improved field on a south-west facing slope in Hampshire, on the edge of the small village of Kings Somborne, west of Winchester. The site is surrounded by farmland, mostly arable, and woodland. The vegetation comprises a fairly uniform sward, classified as MG1a along the sampling transect. Site C15 (Grid reference: SZ432811): This is a 5ha, arable reversion field on a south facing cliff top in the Isle of Wight. The site lies on the south-west facing coast above Brighstone Bay, surrounded by arable farmland and without any tree cover
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so is completely exposed to onshore winds. The vegetation comprises a fairly uniform sward with little floral interest, which has been tentatively classified as MG6a along the sampling transect. Site C16 (Grid reference: SZ496758): This is a 1ha, improved field on an undulating, west facing valley floor, situated on the coast at St. Catherine’s Point, the most southerly point on the Isle of Wight. The valley faces the sea and is edged by a very high, steep cliff along its north side, with scrubby woodland at the far end and along its southern side. The vegetation, classified as MG5 along the sampling transect, comprises a short, tussocky sward with patches of Cirsium and Dioica. Site C17 (Grid reference: SZ546774): This is a 2ha, unimproved field on a shallow south-west facing slope, on the edge of Ventnor, Isle of Wight. The site is coastal, situated adjacent a sports field, with woodland on the upper valley slopes and a residential area below. The vegetation comprises a variable height sward with much re-growth of cleared areas, and has been classified as M1a along the sampling transect. Site C18 (Grid reference: SZ620862): This is a 6ha, semi-improved field near the coast on Bembridge Down at Culver Cliffs, Isle of Wight. The site lies beneath a National Trust owned Fort and the vegetation comprises a short, patchy sward dotted with Cirsium, and classified as MG6c along the sampling transect. Site C19 (Grid reference: TQ026489): This is a 3ha, arable reversion field on a south facing, very gentle slope in Surrey on the edge of Guildford, adjacent the North Downs Way and sandwiched between housing and woodland. The site is edged with trees and scrub, and the vegetation comprises a short, tussocky sward, classified as MG6a along the sampling transect. Site C20 (Grid reference: TQ085489): This is a 3.5ha, unimproved field on a gentle, south-east facing slope in Surrey, north of the A25 mid way between Dorking and Guildford. The site is surrounded by farmland, mostly semi-improved, and woodland. The vegetation comprises a short to medium height sward interspersed with small, scrubby bushes, and classified as CG2a along the sampling transect Site C21 (Grid reference: TQ164539): This is a 0.5ha, semi-improved field on a gentle, east facing slope in Norbury Park, just south of Leatherhead in Surrey. The site is surrounded by trees and trackways, and has a rail tunnel cut beneath it. The vegetation comprises a variable height sward, classified as MG1d along the sampling transect. Site C22 (Grid reference: TQ154541): This is a 1ha, semi-improved flat field on top of a small hill in Norbury Park, just south of Leatherhead in Surrey. The site is surrounded by trees and trackways, and the vegetation has been classified as MG1a along the sampling transect. Site C23 (Grid reference: TQ257616): This is a 1ha, unimproved flat site, situated within Banstead Downs, north of the A23 mid way between Croydon and Leatherhead. The site lies in a large clearing near an old schooling ring for horses, crossed with footpaths and much used by dog walkers. The vegetation comprises a variable height sward with some scrub, classified as CG2a along the sampling transect. Site C24 (Grid reference: TQ258615):
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This is a 2ha, unimproved flat site, which is situated close to site 23 within Banstead Downs, north of the A23 mid way between Croydon and Leatherhead. The transect, classified as CG2a, lies in a strip of tall, dense vegetation, alongside a well used, rutted dirt track. Site C25 (Grid reference: TQ441615): This is a 1.5ha, unimproved field on a gentle, west facing slope, south-west of Orpington in Kent and close to the small airport at Biggin Hill. The site, which is reached by farm track, is situated downslope of a long belt of woodland with arable fields on the valley floor below. The transect, classified as CG2c, lies in small glades amongst new and old scrub. Site C26 (Grid reference: TQ514619): This is a 4.5ha, improved field on a steep, east facing slope in Kent, overlooking the village of Shoreham. The site lies amongst farmland and there is a large area of woodland, Meenfield Wood, on the hilltop above. The vegetation has been classified as MG7b along the sampling transect. Site C27 (Grid reference: TQ513616): This is a 5.5ha, improved field on a steep, east facing slope in Kent, overlooking the village of Shoreham and situated adjacent site C26. The vegetation has been classified as MG7a along the sampling transect. Site C28 (Grid reference: TQ509617): This is a 4ha, arable reversion field on a north-west facing slope in Kent, near the village of Shoreham. The site lies amongst farmland - pasture and other arable reversion fields - and woodland. The vegetation has been classified as MG6a along the sampling transect. Site C29 (Grid reference: TQ508616): This is a 7ha, arable reversion field on a north-east facing slope in Kent, near the village of Shoreham. The site lies adjacent site 28 and the vegetation has been classified as MG6a along the sampling transect. Site C30 (Grid reference: TQ645612): This is a 4.5ha, unimproved field on a south facing slope, just north of junction 3 of the M20/M26 between Sevenoaks and Maidstone. The site lies amongst woodland in Troseley Country Park, which is situated on the North Downs Way. The vegetation has been classified as CG3a along the sampling transect. Site C31 (Grid reference: TQ642611): This is a 3ha, unimproved field on a south facing slope, just north of junction 3 of the M20/M26 between Sevenoaks and Maidstone. The site lies close to site 30 amongst the woodland of Troseley Country Park. The vegetation has been classified as CG3a along the sampling transect. Site C32 (Grid reference: TQ830574): This is a 21ha, arable reversion field on a south-west facing slope in Kent, east of Maidstone. Situated on the North Downs Way, the site lies amongst small villages and patches of woodland. The vegetation comprises a tall, uniform sward, classified as MG5b along the sampling transect. Site C33 (Grid reference: TR229380): This is an 8ha, unimproved field on a steep, south facing slope on Creteway Down, an AONB on the outskirts of Folkestone, Kent. The vegetation comprises a mix of tussocky grass, scrub and gorse and the transect has been classified as CG2b.
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Site C34 (Grid reference: TR236378): This is a 10.5ha, unimproved field on a steep, south facing slope on Creteway Down, an AONB on the outskirts of Folkestone, Kent. The transect, classified as CG4c, lies close to two pill boxes, a large patch of gorse and piece of rough grassland. Site C35 (Grid reference: TR283394): This is a 4.5ha, semi-improved field on a steep, north-west facing slope in Kent, just north of the A20 on the edge of Dover. The site is situated amongst farmland, pasture and arable, and north of Samphire Hoe Country Park. The vegetation, classified as CG2c along the sampling transect, comprises a tussocky sward with occasional scrub patches and mature trees. Site C36 (Grid reference: TR294401): This is a 4ha, unimproved field near the top of a steep, north facing slope in Kent two fields along from site C35. It is a scrubby, uneven site with slumped patches of bare earth; the transect, classified as CG2c, runs between two pill boxes. Site C37 (Grid reference: TR293402): This is a 4ha, arable reversion field on a north-west facing slope in Kent, situated below site C36. The vegetation comprises a variable, patchy sward, classified as MG1 along the sampling transect. Site C38 (Grid reference: TR301403): This is a 5.5ha, unimproved field on a steep, north facing slope in Kent adjacent sites C36 and C37. The vegetation, classified as CG2c along the sampling transect, comprises a very patchy sward, some of which is regrowth following clearance. Site NC1 (Grid reference: SZ636855): This is an 8ha, unimproved field on a south facing cliff top on Bembridge Down at Culver Cliffs, Isle of Wight, close to site C18. On, or adjacent, the site are a monument, battery and gun emplacements, some tumuli and coastguard cottages. The site is used regularly by walkers. The vegetation is mostly a short sward, taller towards sampling point A, and has been classified as CG2a along the sampling transect. Site NC2 (Grid reference: SZ481838): This is a 3.5ha, unimproved field on a steep, south-east facing slope on the edge of the village of Chillerton in the centre of the Isle of Wight. The site is surrounded by farmland, mainly arable, a number of disused quarries and an ancient earthwork. The vegetation comprises a short sward and has been classified as CG2a along the sampling transect. Site NC3 (Grid reference: SP962164): This is a 5ha, improved field on a gentle, east facing slope in Buckinghamshire, east of Ivinghoe. The site, Ivinghoe Hills, is part of National Trust land and can be reached from the road by the Icknield Way Path. The vegetation comprises a fairly uniform sward, classified as MG7a along the sampling transect. Site NC4 (Grid reference: TQ513622): This is a 3ha, improved field on a gentle, north facing slope in Kent, near the village of Shoreham. The site lies amongst farmland - pasture and other arable reversion fields - and woodland, and close to sites C26, C27, C28 and C29. The vegetation was classified as MG7a along the sampling transect from the first year of sampling, however further sampling was discontinued as the field had been returned to crop.
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Experimental sites BACOMBE HILL (LNR) Grid ref: SP860073 Location: south-west edge of Wendover, Bucks; part of ridgeway Slope: north facing; some areas more or less flat Use: Recreational, dog walking, etc.; cattle grazing Description: Mix of: scrub; long standing chalk grassland; cleared scrub (1st cleared strips in 60’s for rabbit shooting; from 1991 – chronosequence clearance over 7-8 years for conservation purposes) History: entire area = open grassland in living memory; by 60’s – much of site scrubbed over BRUSH HILL (LNR) – scrub site Grid ref: SP819035 Location: eastern edge of Princes Risborough, Bucks; edge of ridgeway Slope: west facing. Site overlooks P. Risborough Use: Recreational, dog walking, etc.; Description: Mix of: scrub; chalk grassland glades; cleared scrub (1997-99) History: new reserve - set up June 1997. Run by Wycombe District Council and Butterfly Conservation. Pre 20’s – entire site strip cultivated for arable. 1920’s to 1960’s – management unclear. 1960’s – no longer cultivated, scrub encroachment. Recently – cattle then sheep grazing (NB. But have only ever seen the sheep in the grassland experimental field, not this scrub area) BRUSH HILL (LNR) – grassland experimental site Grid ref: SP819033 Location: eastern edge of Princes Risborough, Bucks; edge of ridgeway Slope: west facing. Use: Primary use = sheep pasture but is one point of access to rest of reserve so probably used by walkers etc. too. Description: fairly steeply sloping field adjacent road, with woodland along non-road edges including bottom edge where plots are. WHINLESS DOWN Grid ref: TR297416 Location: Tower Hamlets area of Dover, ie. eastern edge of Dover. Slope: south facing Use: recreational plus a few cattle grazing Description: Mix of: scrub; chalk grassland glades; cleared scrub (1997/98 and 98/99; the two sites cleared in 97/98 were affected by fire at some point but no indication if this was accidental or the clearance method) History: none available
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COLDBLOW FARM AR SITE Grid ref: TR085447 Location: south east of Wye, just off road to Hastingleigh Slope: south facing Use: sown 1992. Sheep pasture. Description: field on top of downs escarpment above good quality chalk grassland on Wye Downs National Nature Reserve. Plots located near disused chalk pit. COLDBLOW FARM PP SITE Grid ref: TR086446 Location: south east of Wye, just off road to Hastingleigh Slope: west facing Use: sheep pasture Description: field on top of downs escarpment above good quality chalk grassland on Wye Downs National Nature Reserve.
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Appendix 4: Further breakdown of the characterisation of the study sites
Table A1. Geographic / ELMS replicate sites. U: unimproved, SI: semi- improved, I: improved and AR: arable reversion.
U SI I AR ESA - South Wessex Downs 16 0 7 0 ESA - South Downs 8 5 9 9 CS - Chilterns, Isle of Wight 19 7 6 10
Table A2. Overview of Agreement and Non-agreement sites included in the monitoring programme for the ESAs.
U SI I
A N-A A N-A A N-A
SWD 10 5 5 3
SD 5 3 5 5 4
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Appendix 5: Notable Coleoptera Species Family Species Classification CARABIDAE Amara consularis Nationally notable (scarce) category B = notable B CARABIDAE Bembidion gilvipes Nationally notable (scarce) category B = notable B CARABIDAE Harpalus ardosiacus Nationally notable (scarce) category B = notable B CARABIDAE Harpalus azureus Nationally notable (scarce) category B = notable B CARABIDAE Harpalus dimidiatus Nationally notable (scarce) category B = notable B CARABIDAE Licinus depressus Nationally notable (scarce) category B = notable B CARABIDAE Zabrus tenebrioides Nationally notable (scarce) category A = notable A HYDROPHILIDAE Cryptopleurum crenatum Nationally notable (scarce) = notable PTILIIDAE Ptilium exaratum Nationally notable (scarce) = notable LEIODIDAE Agathidium marginatum Nationally notable (scarce) = notable LEIODIDAE Ptomaphagus varicornis RDB K = insufficiently known SCYDMAENIDAE Euconnus maeklini RDB I = indeterminate SCYDMAENIDAE Nevraphes praeteritus Nationally notable (scarce) = notable SCYDMAENIDAE Scydmoraphes helvolus Nationally notable (scarce) = notable SCYDMAENIDAE Stenichnus poweri RDB K = insufficiently known SCYDMAENIDAE Stenichnus pusillus Nationally notable (scarce) = notable STAPHYLINIDAE Alaobia scapularis Nationally notable (scarce) = notable STAPHYLINIDAE Aleochara verna RDB K = insufficiently known STAPHYLINIDAE Alevonota gracilenta RDB K = insufficiently known STAPHYLINIDAE Amarochara umbrosa Nationally notable (scarce) = notable STAPHYLINIDAE Anotylus hamatus Nationally notable (scarce) = notable STAPHYLINIDAE Atheta aegra Nationally notable (scarce) = notable STAPHYLINIDAE Atheta benicki RDB K = insufficiently known STAPHYLINIDAE Atheta inquinula Nationally notable (scarce) = notable STAPHYLINIDAE Atheta puberula RDB K = insufficiently known STAPHYLINIDAE Brachida exigua RDB I = indeterminate STAPHYLINIDAE Ilyobates propinquus Nationally notable (scarce) = notable STAPHYLINIDAE Lamprinodes saginatus Nationally notable (scarce) category A = notable A STAPHYLINIDAE Liogluta pagana Nationally notable (scarce) = notable STAPHYLINIDAE Omalium rugatum Nationally notable (scarce) = notable STAPHYLINIDAE Oxypoda exoleta Nationally notable (scarce) = notable STAPHYLINIDAE Oxypoda lurida Nationally notable (scarce) = notable
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STAPHYLINIDAE Philonthus nitidicollis Nationally notable (scarce) category B = notable B STAPHYLINIDAE Rugilus similis Nationally notable (scarce) = notable STAPHYLINIDAE Rugilus subtilis RDB I = indeterminate STAPHYLINIDAE Stenus contumax Nationally notable (scarce) = notable STAPHYLINIDAE Stenus fuscicornis Nationally notable (scarce) category B = notable B STAPHYLINIDAE Sunius melanocephalus Nationally notable (scarce) = notable PSELAPHIDAE {now generally treated as a subfamily of Amauronyx maerkelii RDB 3 = rare Staphylinidae} PSELAPHIDAE {now generally treated as a subfamily of Claviger testaceus Nationally notable (scarce) = notable Staphylinidae} PSELAPHIDAE {now generally treated as a subfamily of Euplectus kirbyi Nationally notable (scarce) = notable Staphylinidae} SCARABAEIDAE Aphodius consputus RDB 3 = rare SCARABAEIDAE Euheptaulacus villosus Nationally notable (scarce) category A = notable A BUPRESTIDAE Aphanisticus pusillus Nationally notable (scarce) category B = notable B BUPRESTIDAE Trachys scrobiculatus Nationally notable (scarce) category A = notable A CANTHARIDAE Malthinus balteatus Nationally notable (scarce) category B = notable B ANOBIIDAE Hemicoelus fulvicornis RDB I = indeterminate NITIDULIDAE Meligethes erichsonii Nationally notable (scarce) = notable NITIDULIDAE Meligethes solidus Nationally notable (scarce) = notable CRYPTOPHAGIDAE Atomaria rubricollis RDB I = indeterminate CRYPTOPHAGIDAE Atomaria scutellaris RDB K = insufficiently known BOTHRIDERIDAE {was part of Cerylonidae} Anommatus Nationally notable (scarce) category A = notable A duodecimstriatus COCCINELLIDAE Scymnus femoralis Nationally notable (scarce) category B = notable B COCCINELLIDAE Scymnus schmidti Nationally notable (scarce) category B = notable B MORDELLIDAE Mordellistena parvula RDB K = insufficiently known MORDELLIDAE Mordellistena pygmeola RDB K = insufficiently known CHRYSOMELIDAE Aphthona nigriceps Nationally notable (scarce) category A = notable A CHRYSOMELIDAE Batophila aerata Nationally notable (scarce) category B = notable B CHRYSOMELIDAE Cassida hemisphaerica Nationally notable (scarce) category A = notable A CHRYSOMELIDAE Cassida prasina Nationally notable (scarce) category B = notable B CHRYSOMELIDAE Cryptocephalus bilineatus Nationally notable (scarce) category B = notable B CHRYSOMELIDAE Cryptocephalus bipunctatus Nationally notable (scarce) category B = notable B
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CHRYSOMELIDAE Longitarsus dorsalis Nationally notable (scarce) category B = notable B CHRYSOMELIDAE Longitarsus fowleri Nationally notable (scarce) category A = notable A CHRYSOMELIDAE Longitarsus lycopi Nationally notable (scarce) category B = notable B CHRYSOMELIDAE Longitarsus nigrofasciatus Nationally notable (scarce) category A = notable A CHRYSOMELIDAE Longitarsus parvulus Nationally notable (scarce) category A = notable A CHRYSOMELIDAE Phyllotreta vittula Nationally notable (scarce) category A = notable A CHRYSOMELIDAE Psylliodes chalcomera Nationally notable (scarce) category B = notable B CHRYSOMELIDAE Psylliodes luteola RDB K = insufficiently known ANTHRIBIDAE Choragus sheppardi Nationally notable (scarce) category A = notable A APIONIDAE Apion affine Nationally notable (scarce) category A = notable A APIONIDAE Apion cerdo Nationally notable (scarce) category B = notable B APIONIDAE Apion cineraceum Nationally notable (scarce) category A = notable A APIONIDAE Apion difforme Nationally notable (scarce) category B = notable B APIONIDAE Apion flavimanum Nationally notable (scarce) category A = notable A APIONIDAE Apion pubescens Nationally notable (scarce) category B = notable B APIONIDAE Apion stolidum Nationally notable (scarce) category B = notable B CURCULIONIDAE Acalles ptinoides Nationally notable (scarce) category B = notable B CURCULIONIDAE Brachysomus echinatus Nationally notable (scarce) category B = notable B CURCULIONIDAE Cathormiocerus socius RDB 2 = vulnerable CURCULIONIDAE Ceutorhynchus campestris Nationally notable (scarce) category B = notable B CURCULIONIDAE Ceutorhynchus euphorbiae Nationally notable (scarce) category A = notable A CURCULIONIDAE Ceutorhynchus moelleri RDB K = insufficiently known CURCULIONIDAE Ceutorhynchus pilosellus RDB 2 = vulnerable CURCULIONIDAE Ceutorhynchus punctiger Nationally notable (scarce) category B = notable B CURCULIONIDAE Ceutorhynchus terminatus Nationally notable (scarce) category B = notable B CURCULIONIDAE Ceutorhynchus trimaculatus Nationally notable (scarce) category B = notable B CURCULIONIDAE Gymnetron melanarium Nationally notable (scarce) category B = notable B CURCULIONIDAE Gymnetron rostellum Nationally notable (scarce) category A = notable A CURCULIONIDAE Hypera fuscocinerea Nationally notable (scarce) category B = notable B CURCULIONIDAE Hypera meles Nationally notable (scarce) category A = notable A CURCULIONIDAE Larinus planus Nationally notable (scarce) category B = notable B CURCULIONIDAE Miarus graminis Nationally notable (scarce) category B = notable B CURCULIONIDAE Mitoplinthus caliginosus Nationally notable (scarce) category A = notable A CURCULIONIDAE Orthochaetes insignis Nationally notable (scarce) category B = notable B
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CURCULIONIDAE Orthochaetes setiger Nationally notable (scarce) category B = notable B CURCULIONIDAE Rhynchaenus pratensis Nationally notable (scarce) category B = notable B CURCULIONIDAE Sitona macularius Nationally notable (scarce) category B = notable B CURCULIONIDAE Sitona waterhousei Nationally notable (scarce) category B = notable B CURCULIONIDAE Smicronyx jungermanniae Nationally notable (scarce) category B = notable B CURCULIONIDAE Smicronyx reichi RDB 3 = rare CURCULIONIDAE Strophosoma faber Nationally notable (scarce) category B = notable B CURCULIONIDAE Trachyphloeus alternans Nationally notable (scarce) category B = notable B CURCULIONIDAE Trachyphloeus aristatus Nationally notable (scarce) category B = notable B CURCULIONIDAE Trachyphloeus asperatus Nationally notable (scarce) category B = notable B CURCULIONIDAE Trachyphloeus spinimanus Nationally notable (scarce) category B = notable B CURCULIONIDAE Trichosirocalus horridus Nationally notable (scarce) category A = notable A CURCULIONIDAE Trichosirocalus rufulus Nationally notable (scarce) category A = notable A CURCULIONIDAE Tychius lineatulus Nationally notable (scarce) category A = notable A CURCULIONIDAE Tychius polylineatus RDB K = insufficiently known CURCULIONIDAE Tychius pusillus Nationally notable (scarce) category B = notable B CURCULIONIDAE Tychius squamulatus Nationally notable (scarce) category B = notable B CURCULIONIDAE Zacladus exiguus Nationally notable (scarce) category B = notable B
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Appendix 6: Results Tables
Table A3. Differences of the invertebrate and vegetation communities for the four different grassland types monitored. U: unimproved, SI: semi-improved, I: Improved, AR: arable reversion.
Grassland type U SI I AR (n = 42) (n = 13) (n = 22) (n = 19) Mean Mean Mean Mean Coleoptera number of species 58.2˜ 62.0ˆ,ˇ 51.3 49.7 Auchenorrhyncha number of species 24.0**,˜˜ 23.2 18.0 17.5 Heteroptera number of species 15.5**,˜˜ 13.3(ˇ) 9.8 9.8 Hemiptera number of species 39.5**,˜˜ 36.5 27.8 27.3 Number of all species 97.7(*),˜ 98.5ˆ,ˇ 79.1 77.1 Coleoptera number of individuals 433.5 496.9(ˆ),ˇ 360.5 368.5 Auchenorrhyncha number of individuals 347.8 400.3 426.2 397.4 Heteroptera number of individuals 219.2**, ª,˜˜ 76.8ˇ 51.1 43.3 Hemiptera number of individuals 567.1(˜) 477.1 477.3 440.7 Total number of all individuals 1000.6˜ 974.0 837.8 809.2 Plant diversity (Schannon-Weaner) 2.2*,˜˜ 2.1ˇˇ 1.8 1.4˚ Chalk grassland Auc. species number 4.5**,ª,˜˜ 2.8ˆ,ˇ 1.5 1.2 Dry grassland Auc. species number 7.6**,ª,˜˜ 5.0 3.0 3.0 Euryoecic Auc. species number 9.0 10.5ˆ 8.6 9.1 Nitrophilous Auc. species number 5.2ª,˜˜ 7.0 6.1 7.1˚ Notable insect species number 5.9*,˜ 5.9 4.2 3.9 Notable Coleoptera species number 5.5(*),˜ 5.8 4.1 3.9 Notes: 1. Comparison U v I: *significant (P ≤ 0.05), **highly significant (P ≤ 0.001), (*) trend (P ≤ 0.06) 2. Comparison U v SI: ª significant (P ≤ 0.05), ªª highly significant (P ≤ 0.001), (ª) trend (P ≤ 0.06) 3. Comparison U v AR: ˜ significant (P ≤ 0.05), ˜˜ highly significant (P ≤ 0.001), (˜) trend (P ≤ 0.06) 4. Comparison SI v I: ˆ significant (P ≤ 0.05), ˆˆ highly significant (P ≤ 0.001), (ˆ) trend (P ≤ 0.06) 5. Comparison SI v AR: ˇ significant (P ≤ 0.05), ˇˇ highly significant (P ≤ 0.001), (ˇ) trend (P ≤ 0.06) 6. Comparison I v AR: ˚ significant (P ≤ 0.05), ˚˚ highly significant (P ≤ 0.001), (˚) trend (P ≤ 0.06)
Table A4. The effect of vegetation structure on the diversity and abundance of the invertebrates. Vegetation height ≤ 6.5 cm > 6.5cm - ≤ 10 cm > 10 cm Mean (n = 27) mean (n = 24) mean (n = 26) Coleoptera number of species 50.0ªª 53.5˜ 67.1 Auchenorrhyncha number of species 17.4*,ªª 21.7˜ 27.5 Heteroptera number of species 9.7*,ªª 13.3˜ 17.6 Hemiptera number of species 27.1*,ªª 35.0˜˜ 45.1 Number of all species 77.2(*),ªª 88.5˜˜ 112.2 Coleoptera number of individuals 370.0ª 427.8 474.7 Auchenorrhyncha number of individuals 310.5ª 441.3 392.9 Heteroptera number of individuals 161.1 184.2 98.4 Hemiptera number of individuals 471.7 625.5 491.3 Total number of individuals 841.7* 1053.3 966.0 Plant diversity (Schannon-Weaner) 2.2 1.9 2.1 chalk grassland Auc. species number 2.5ª 3.1˜ 4.4 dry grassland Auc. species number 4.6ª 5.7 7.4 Euryoecic Auc. species number 7.7ª 9.2 10.6 Nitrophilous Auc. species number 5.1ª 5.8 6.4 Notable insect species number 5.2 4.8˜ 6.2 Notable Coleoptera species number 5.1 4.5 5.8 Notes: 1. Comparison low v medium: * significant (P ≤ 0.05), ** highly significant (P ≤ 0.001), (*) trend (p ≤ 0.06) 2. Comparison low v high: ª significant (P ≤ 0.05), ªª highly significant (P ≤ 0.001), (ª) trend (p ≤ 0.06) 3. Comparison medium v high: ˜ significant (P ≤ 0.05), ˜˜ highly significant (P ≤ 0.001), (˜) trend (p ≤ 0.06)
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Table A5. The effect of plant diversity on the diversity and abundance of the invertebrates. Plant diversity (Shannon-Weaner) Low (<2.15) High (>2.15) mean (n = 38) mean (n = 39) Coleoptera number of species 53.5 60.2 Auchenorrhyncha number of species 20.9 23.4 Heteroptera number of species 11.6* 15.4 Hemiptera number of species 32.5* 38.7 Total number of all species 86.0* 98.9 Coleoptera number of individuals 369.0* 476.4 Auchenorrhyncha number of individuals 405.1 353.7 Heteroptera number of individuals 91.3** 201.6 Hemiptera number of individuals 496.4 555.3 Total number of all individuals 865.4 1031.7 chalk grassland Auc. species number 2.6* 4.1 dry grassland Auc. species number 4.7* 7.0 euryoecic Auc. species number 9.3 9.0 Nitrophilous Auc. species number 6.0 5.5 notable insect species number 4.3** 6.5 notable Coleoptera species number 4.1** 6.2 Notes: Comparison low v high plant diversity: * significant (P ≤ 0.05), ** highly significant (P ≤ 0.001), (*) nearly significant (p ≤ 0.06)
Table A6. The effect of plant species richness on the diversity and abundance of the invertebrates. Plant species richness <40 plant species ≥40 plant species mean (n = 38) mean (n = 39) Coleoptera number of species 52.5* 61.2 Auchenorrhyncha number of species 18.5** 25.7 Heteroptera number of species 10.9** 16.1 Hemiptera number of species 29.4** 41.8 Total number of all species 81.8** 102.9 Coleoptera number of individuals 376.4* 469.1 Auchenorrhyncha number of individuals 373.7 384.3 Heteroptera number of individuals 114.8* 178.7 Hemiptera number of individuals 488.4 563.1 Total number of all individuals 864.9 1032.2 chalk grassland Auc. species number 2.3** 4.4 dry grassland Auc. species number 4.3** 7.4 euryoecic Auc. species number 8.6 9.6 Nitrophilous Auc. species number 5.6 5.9 notable insect species number 4.9 5.9 notable Coleoptera species number 4.8 5.5 Notes: Comparison low v high plant species richness: * significant (P ≤ 0.05), ** highly significant (P ≤ 0.001), (*) trend (p ≤ 0.06)
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Table A7. The effect of site size / area on the diversity and abundance of the invertebrates. Site size > 10 ha (n = 20) > 10 ha (n = 22) Average site size 4.4 21.5 Coleoptera number of species 58.2 58.2 Auchenorrhyncha number of species 24.3 23.8 Heteroptera number of species 16.2 14.8 Hemiptera number of species 40.5 38.6 Total number of all species 98.7 96.8 Coleoptera number of individuals 413.8 451.5 Auchenorrhyncha number of individuals 331.4 362.8 Heteroptera number of individuals 218.1 220.3 Hemiptera number of individuals 549.5 583.1 Total number of all individuals 963.3 1034.6 plant diversity 2.1 2.2 chalk grassland Auc. species number 4.6 4.4 dry grassland Auc. species number 7.5 7.7 euryoecic Auc. species number 9.0 9.0 nitrophilous Auc. species number 5.2 5.1 notable insect species number 6.1 5.7 notable Coleoptera species number 5.7 5.3
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Appendix 7: Further analyses and discussion of the effects of vegetation structure on invertebrate assemblages.
correlation veg.-height and inv. species richness on improved grassland
140 R2 = 0.3072 120 F = 8.868, P< 0.008 100 1,20 80 Series1 60 Linear (Series1) species 40 20
0 number invertebrate number invertebrate 0 10 20 30 average vegetation height
correlation veg.-height and coleoptera species richness on improved grassland
100 R2 = 0.2433
80 F1,20 =6.430, P< 0.02
60 Series1
40 Linear (Series1) species 20
0 number of coleoptera of coleoptera number 0 10 20 30 average vegetation height
A reduced vegetation height leads to a loss of structural diversity and subsequently to a reduced invertebrate species richness. The same is true with a reduction of plant species richness, which effects phytophages more than predatory insects (as presented as a poster paper at the British Ecological Society Annual Meeting for unimproved grasslands). On Improved grassland, this effect might not be true or is less distinct due to the negative effects of dense vegetation on invertebrates (e.g. higher humidity and lower temperatures on ground level, lower plant diversity due to lack of open ground and consequently a higher failure of recolonisation by chalk grassland plants etc.). However, we can't conclusively demonstrate this hypothesis from this project and is an area needing further research. In contrast, on improved and arable reversion sites the species richness of invertebrates (mainly the Coleoptera, a large and species rich group) is still significantly positively correlated with the growing height of vegetation.
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Appendix 8: (A) Variance partitioning for 1998 (ESA)/1999 (CSS) Survey Auchenorrhyncha Env. Variable Co-variable % variance expl. P (Monte Carlo) Region (R) V, S, G, NVC 5.7 0.002 Vegetation (V) R, S, G, NVC 3.9 0.108 Site factors (S) R, V, G, NVC 4.9 0.056 Grazing (G) R, V, S, NVC 4.4 0.172 NVC R, V, S, G 10.3 0.002 R, V, S, G, NVC - 48.8 0.002 Phytophagous beetles Env. Variable Co-variable % variance expl. P (Monte Carlo) Region (R) V, S, G, NVC 5.9 0.002 Vegetation (V) R, S, G, NVC 4.5 0.022 Site factors (S) R, V, G, NVC 6.1 0.006 Grazing (G) R, V, S, NVC 5.3 0.024 NVC R, V, S, G 7.7 0.004 R, V, S, G, NVC - 40.5 0.002 Heteroptera Env. Variable Co-variable % variance expl. P (Monte Carlo) Region (R) V, S, G, NVC 3.8 0.078 Vegetation (V) R, S, G, NVC 6.4 0.002 Site factors (S) R, V, G, NVC 5.8 0.076 Grazing (G) R, V, S, NVC 4.5 0.442 NVC R, V, S, G 7.8 0.014 R, V, S, G, NVC - 34.6 0.002
(B) Variance partitioning for 2000 (ESA)/2002 (CSS) Survey Auchenorrhyncha Env. Variable Co-variable % variance expl. P (Monte Carlo) Region (R) V, S, G, NVC 5.6 0.002 Vegetation (V) R, S, G, NVC 4.6 0.024 Site factors (S) R, V, G, NVC 5.7 0.002 Grazing (G) R, V, S, NVC 3.5 0.676 NVC R, V, S, G 11.8 0.002 R, V, S, G, NVC - 45.9 0.002 Phytophagous beetles Env. Variable Co-variable % variance expl. P (Monte Carlo) Region (R) V, S, G, NVC 6.0 0.002 Vegetation (V) R, S, G, NVC 5.0 0.008 Site factors (S) R, V, G, NVC 4.5 0.242 Grazing (G) R, V, S, NVC 4.1 0.522 NVC R, V, S, G 8.6 0.002 R, V, S, G, NVC - 41.1 0.002 Heteroptera Env. Variable Co-variable % variance expl. P (Monte Carlo) Region (R) V, S, G, NVC 4.7 0.006 Vegetation (V) R, S, G, NVC 5.4 0.026 Site factors (S) R, V, G, NVC 6.3 0.042 Grazing (G) R, V, S, NVC 4.1 0.802 NVC R, V, S, G 7.6 0.032 R, V, S, G, NVC - 33.6 0.002
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Appendix 9: Multi-variate analyses and plots of site factors and management practices on invertebrate assemblages.
0.6
Sheep
Aph euph
Api walt Cas rubi Tim goet Sit wate Cry fulv Lon obli
Cha hort Tra trog Cry bili Cha conc Gym labi Lon fowl Api cine Aph herb South SD
Tyc pici North Lon parv East Tyc line Api onop Man matt Api vire Sit lepi Api pisi Tra scro Apha pus Api tenu Mec pyra Rhi peri Api seni
Tra alte Ungrazed Api fulv SWD Tra aspe
Oti lign Lon succ Ceu pall
Sit hisp Ort seti Neo ferr Lon prat Api assi Api apri
West
Lon luri Neo tran Cattle
Sit line -0.4 -0.4 0.6
(A) 1998_99 Biplot of phytophagous beetles from ESA unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 13.4% & Axis 2 = 10.5%. Model = R+A+G explained 44.6% P<0.01.
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0.8
MG5
Ungrazed
Hyl eleg
Ano albi Rho adum Xan stra Del meso North Moc atte Meg quad
Cen corn Jav obsc Kel irre Eus line Eva inte East Mac fusc Con obso
Mue fair West CG2
Cic pers
CG3-5 Psa ceph Ana riba Sheep Cattle Eup cusp
South
Kos exig -0.4 -0.4 1.0
(B) 1998_99 Biplot of auchenorrhyncha from ESA unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 14.0% & Axis 2 =12.7%. Model = A+G+NVC explained 45.2% P<0.05.
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0.8
16
17 7
MG5
Ungrazed 17 16
17 North 14 20 14 8 East 4 6 15 20 West 9 CG2
11 CG3-5 Sheep Cattle
South 11
12
14
4 10 14
13 -0.8 -0.8 1.0
C) 1998_99 Biplot of auchenorrhyncha species richness from ESA unimproved sites. Circles represent individual sites with larger circles indicating high species richness. Triangles represent centroids of sites falling into each category of environmental variables. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Variance in species assemblages explained by Axis 1 = 14.0% & Axis 2 =12.7%. Model = A+G+NVC explained 45.2% P<0.05.
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0.6
Chiltern Man matt
Aph herb Api conf Cha conc
Sph rubi Ser hale
Alt oler Lon obli
Tra spin Phy undu Ceu term Api trif Alt pusi Lon parv CG3-5 Flat Lon fowl Rhy fagi Api onop
South
Sit line
Api stol Hyp plan Alt sp Tra scab
Cha hort Api flav CG2 Psy chry Api tenu
Lon atri East ND Tyc junc Lon prat Lon grac Tra aspe Api vire Lon flav Tri trog West Oti lign Lon memb Sit hume Cry fulv Ort insi Chr bank Aca mise Bar pell Api cine Phy robo Tra alte Api seni Lon luri Tyc pusi Api loti Api fulv Veg hei
SD North -0.4 -0.6 0.6
(D) 1998_99 Biplot of phytophagous beetles from CSS unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 22.2% & Axis 2 = 13.7 %. Model = R+A+VH+NVC explained 63.9 % P<0.01.
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0.5
SD
East West Xan stra Chiltern North
Dik vari Moc atte
Err ocel Meg quad Ano serr Del meso Meg scan For citr All mixt Jav pell Flat Kos exig Bat irro Cic pers Mue fair Arb parv Cic viri Hyl eleg Str sord
Not flav Rhy proc Eva inte
Ana veno
Aph bici South
Eup cusp Tur soci
ND -0.3 -0.6 0.6
(E) 1998_99 Biplot of auchenorrhyncha from CSS unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 18.4% & Axis 2 =10.9 %. Model = R+A explained 49.8 % P<0.01.
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1.0 MG1
Api aeth
Sit sutu Api fili Sph test Lon sutu
Lon grac
Api tenu
Lon flav
Hyp punc
Sit hisp Neo ferr Lon luri Gym pasc Hyp nigr MG7 Phy vitt Ceu dist Sit gran Api pisi Sit lepi Aph nigr Api vire Oul mela Api seni
Api fulv Api diff Tyc pici
Lon succ MG6 Sit line
Lon prat Hyp mele Api loti Ceu obst Api cine Tyc pusi Alt sp Cha hort Ceu camp Phy nigr Api pube Hyp venu Tra alte MG5 Tra aspe Api onop Lon atri
Lon parv -0.6 -0.6 1.0
(F) 1998_99 Biplot of phytophagous beetles from AR sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 18.9% & Axis 2 =5.9 %. Model = NVC explained 31.9 % P<0.01.
(G) 1998_99 Biplot of auchenorrhyncha from AR sites. NOT SIGNIFICANT.
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0.5 SD
Tyc pici
Api fulv Ser hale Api pisi Rhy prat Api cine Cry bili Api loti Tra angu Api stol Alt oler Lon pell Cha hort Apt orbi Tyc line Tra alte Tyc junc Lon sutu Tra aspe Aph euph Api pube Lon grac Cha arid Neo ferr East Lon fowl Ort seti Cry fulv Lon obli Lon prat South
West Api assi
Api seni Cas pras Lon luri Api walt
Aph herb
Lon parv Api apri Tri trog Apha pus Sit hisp Sit macu Phy atra Phy viri Phy vitt Psy lute North Cha conc
Hyp punc
Api vire Lon atri SWD
Sit line -0.3 -0.4 0.6
(H) 2000_02 Biplot of phytophagous beetles from ESA unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 13.6% & Axis 2 =10.1 %. Model = R+A explained 29.1 % P<0.01.
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0.6
Ungrazed Veg hei
CG3-5
Cen corn Rho adum Del meso Moc croc Other Ana riba Cic pers For citr Ano flav Zyg flam MG5 Meg quad East Str sord Jav obsc Kel irre Mac fusc North Eus line Moc atte West
Sheep South Con obso Sh+Catt
Psa ceph Tha dilu
Eup nota CG2 Cattle
Neo excl -0.4
-0.6 0.8
(I) 2000_02 Biplot of auchenorrhyncha from ESA unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 19.6% & Axis 2 =14.5 %. Model = VH+A+G explained 59.9% P<0.01.
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0.8
19 Veg hei
18
15 Ungrazed 11 12 CG3-5 8
18 19 22
17 5 20 Other East 13 MG5 4
Sh+Catt West Sheep South North
18 Cattle CG2
16
13
4 14 16 8
12 5 -0.8 -0.6 1.2
(J) 2000_02 Biplot of auchenorrhyncha from ESA unimproved sites. Circles represent individual sites with larger circles indicating high species richness. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients.. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 19.6% & Axis 2 =14.5 %. Model = VH+A+G explained 59.9% P<0.01.
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0.4
West Lon sutu Bar aran Sit sutu Hyp post Smi reic Api cine Tyc pusi Api tenu Sit hisp SD Tyc line Api seni Cry fulv Tyc step North Sit hume
Api apri Cry hypo Tra angu Tyc junc Api vire ND Ser hale Api loti Api flav Tra alte Neo quad
Sit sulc Alt oler Tri trog Api fili
Tra aspe Phy robo CG3-5 East Lon prat Cas vibe Tra scab Apt orbi Tim goet Sit line Sph test Str mela Alt sp Mec pyra CG2 Lon parv South Api atom Sph rubi Neo tran Lon fowl Api assi Man matt Apha pus
Lon obli Alt pusi Tyc pici
Flat
Aph herb
Chiltern -0.3 -0.6 0.6
(K) 2000_02 Biplot of phytophagous beetles from CSS unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 24.6% & Axis 2 =9.5 %. Model = R+A+NVC explained 57.9% P<0.01.
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0.8
North
Eus line
Psa ceph
For citr
Aph bici Cen corn Meg quad
Jav pell Psa albo Spe subf Zyg flam Ste minu Fag crue Ano serr ND Ano flav Mac fusc Veg hei Moc atte Chiltern
Kel irre Flat Arb parv Str sord Del meso Mue fair
South Xan stra West SD Rec coro
Tha dilu
Kel gutt
Kos exig Ano albi East Meg scab Eup cusp
Ana riba -0.4 -0.4 0.6
(L) 2000_02 Biplot of auchenorrhyncha from CSS unimproved sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 15.3% & Axis 2 =10.8 %. Model = R+VH+A explained 51.8% P<0.01.
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1.0 12
12
North
27 16
15 15 ND Chiltern 18 Veg hei 10
11 SD Flat 9 21 West South 17 19 20 7 East
18 17
15
21 -0.6
-1.0 1.5
(M) 2000_02 Biplot of auchenorrhyncha species richness from CSS unimproved sites. Circles represent individual sites with larger circles indicating high species richness. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 15.3% & Axis 2 =10.8 %. Model = R+VH+A explained 51.8% P<0.01.
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0.6
SWD
MG5 Chiltern Lon succ
Gym pasc ND Sph rubi Lon mela Hyp post MG6 Mec pyra Aph nigr Lon lyco Api gibb Psy chal Api fili Tri horr Hyp mele MG1 Api nigr Lon grac Sph test Lon flav
Hyp venu Sit hisp Sit hume Api trif Phy robo Api fulv adj Sit sulc Sit line Api assi
Tyc pici Api apri far Phy viri Lon prat Sit lepi Lon luri Api vire
near Tri trog Aph euph Phy diad Phy undu Cha conc Api loti MG7 Lon parv Neo ferr
SD -0.4 -0.6 0.6
(N) 2000_02 Biplot of phytophagous beetles from AR sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 18.2% & Axis 2 =12.4%. Model = R+I+NVC explained 64.7% P<0.01.
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0.8 19
15
10 SWD
MG5 Chiltern
ND 16 14 MG6 14 21 7 MG1
adj 13
far
8 9 19
near MG7 9 6 7 SD 13 26 14
10 -0.8 -0.8 1.0
(O) 2000_02 Biplot of phytophagous beetles from AR sites. Circles represent individual sites with larger circles indicating high species richness. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 18.2% & Axis 2 =12.4%. Model = R+I+NVC explained 64.7% P<0.01.
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0.3 MG1 Other Phi spum
Dik vari Cen corn Sheep
Str aemu CSS SD Con obso
Psa conf Rhy proc Fag crue MG5 Eup nota Tur soci Cattle Rho adum Mac fusc Kos exig Veg hei ND Moc atte Eus line Meg quad Ano albi Sha-Wie Chiltern ESA Ana riba
Eva inte MG6 MG7 Xan stra
Not flav
Sh+Catt SWD
Ungrazed -0.3
-0.4 0.6
(P) 2000_02 Biplot of auchenorrhyncha from AR sites. Triangles represent centroids of sites falling into each category of environmental variables, black arrows represent the direction of increase in continuous environmental gradients. Filled triangle represent variables within environmental factor groups that were sig. at p<= 0.05 in the forward selection process. Open triangles represent variables that although not significant in FS were included to show how the significant group members differed from the rest. Species scores are represented by grey diamonds and an arrow projected from the origin to the species symbols indicates the direction of increase in abundance of a species in ordination space. Variance in species assemblages explained by Axis 1 = 29.6% & Axis 2 = 15%. Model = R+VH+G+NVC+AS explained 73.2% P<0.01.
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Appendix 10: Further investigation into grazing as a management tool and its effects on the vegetation and invertebrate assemblages. Type of grazing stock There is apparently no difference in the overall effects of grazing by sheep, cattle and both, on the vegetation and the invertebrates. However, the biplots (Appendix 9 and main text) indicate that there may be differences in the assemblages of individual groups of invertebrates type on type or combination of grazing stock. Analyses comparing grazed and unmanaged sites elucidated the general effects of grazing as a management tool. However, this area is one which requires significantly more research as it could be fundamental to the long-term success of the Schemes. Obviously, the over-riding effect of grazing by any stock at a reasonable stocking rate is a reduction of sward height and the ability to manipulation vegetation species richness and to a certain extent assemblage composition. However, the analysis here has illustrated an interesting unexpected result (which has been checked), that grazing leads to a reduction in plant species richness on Unimproved sites. This underlines that further research is required here, particularly focusing on grazing animal, time and duration of grazing, a consideration of poaching and stocking rate. Effects of grazing on invertebrates Both grazing by sheep and by cattle reduces the species richness of insects and the abundance of some of the invertebrate orders. This short term negative effect is not only present for the overall number of species within different orders but probably more importantly, also for the highly specialised chalk grassland indicator species, for example for the Auchenorrhyncha. The longer term dynamics are unknown and true long term studies are required to investigate mechanisms and consequences for conservation and the agri-environment schemes. In the following results graphs, all significance testing is done by Mann-Whitney, as indicated by letters above columns in the plots.
50 50 b 45 b a 45 a 40 40 35 35 30 sheep 30 cattle 25 25 none none 20 20 b b 15 a 15 a 10 10 5 5 0 0 average Veg. Height (cm) No plant species from Veg. average Veg. Height (cm) No plant species from Veg. Quadrat Quadrat
Fig A1: effects of (a) sheep and (b) cattle grazing on unimproved grassland: grazing by either animal significantly reduces vegetation height (structure) and plant species richness.
80 b 80 b 70 70 a a 60 60
50 50 sheep cattle 40 40 b b none none 30 a 30 a b 20 20 a 10 10
0 0
Auchenorrhyncha Auchenorrhyncha
Het.+ Auc. noColeoptera species noall species insects no species Het.+ Auc. noColeoptera species noall species insects no species Heteroptera no species Heteroptera no species Fig A2: effects of (a) sheep and (b) cattle grazing on species richness of invertebrates on un-Improved grassland: supporting Fig. A1, species richness of the leafhoppers, Homoptera and all insect together is reduced by grazing by sheep; species richness of the Homoptera and all insects together is reduced by cattle.
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600 b 40 b 500 35 ab ab a a a 400 30 a cattle + sheep cattle + sheep b b sheep 300 25 b ab cattle a ab a ab ab sheep a a a none 20 c 200 cattle 15 100 b none a b a ab b 10 a 0 5 0 veg. Height plant species Auc.specimen Het. specimen Col. Specimen Het.&Auc. specimen all insects specimen Fig A3: Effects of grazing by sheep, cattle and Fig A4: Effects of grazing by sheep, cattle and mixed on vegetation assemblages from mixed on invertebrate abundance (no./m sq) improved and arable reversion sites: Within from improved and arable reversion sites: these communities, mixed grazing consistently Within these communities, grazing had had the greatest impact with the individual sheep inconsistent effects reflecting different or cattle effects being approximately similar. invertebrate lifestyles, feeding strategies and
habits.
80 9 c bc c 8 70 ac 7 60 b a a ab a a a 6 50 a cattle + sheep c cattle + sheep b sheep bc sheep 5 40 ab cattle cattle a c none 4 none 30 a b c b 3 a a 20 bc a ab b a c 2 a ab ab b b 10 a 1
0 0 Auc. Het. Het. & Auc. Col. all insects Species Species Species Species species chalk Auc. dry Auc. eurytopic Auc. nitrophilic Auc.
Fig A5: Effects of grazing by sheep, cattle and Fig A6: Effects of grazing by sheep, cattle and mixed on invertebrate species richness from mixed on specialised Auchenorrhyncha species improved and arable reversion sites: Within richness from improved and arable reversion these communities, grazing had inconsistent sites: Within these communities, grazing had effects reflecting different invertebrate lifestyles, inconsistent effects on number of species in each feeding strategies and habits. group, however, grazing never promoted species richness.
8 b 7 Coleoptera no specimen 6 a
5 300 b b sheep 250 4 none b a 200 a 3 Coleoptera no a 150 specimen 2 100 1 50 0 0 Auc. chalk Auc. dry eurytopic nitrophilous grassl. Sp. grassl. Sp. Auc. Sp. Auc. Sp. sheep none
Fig A7: Effects of grazing by sheep on Fig A8 Effects of sheep grazing on the specialised Auchenorrhyncha species abundance of coleoptera on un-improved sites: richness from un-improved sites: Consistent with Fig. A7, sheep grazing led to a Within these groups grazing consistently reduction in the abundance (number of led to a reduction in leafhopper species specimens) of beetles. richness.
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Appendix 11: Further investigation into site isolation.
Arable reversion and improved sites develop a greater species richness if they are adjacent to existing chalk grassland compared with sites where unimproved grassland is further than 1km away. Examples are given for invertebrate (coleoptera) abundance (number of specimens) and on the number of insect species (species richness). Analyses were conducted by the Mann-Whitney test, columns with different letters are significantly different from each other.
Effect of isolation on no of Coleoptera
70 a 60 ab b 50
40
30
20 no Coleoptera species no Coleoptera 10
0 0 < 1000m >1000m distance to nearest unimproved grassland
Effect of isolation on no of insect species
95 a 90
85 ab 80 b
75 no of insectspecies
70
65 0 < 1000m >1000m distance to nearest unimproved grassland
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Appendix 12: Effects of hay spreading and cultivation on plant species; examples drawn from Brush Hill.
1. Effects of Hay spreading Note all Legends as in Figure 18 legend in main text.
Centaurea nigra at Brush Hill Galium mollugo at Brush Hill
45 9 b 40 8
35 7
30 6 2001 b 2001 25 2000 5 2000 1999 20 4 1999
% coverage 1998 % coverage % 1998 15 3
2 10 a a 1 5 0 0 control cultiv. hay hay+cult. control cultiv. hay hay+cult. treatment treatment
Daucus carota at Brush Hill
12
10
8 2001 2000 6 1999
% coverage % 1998 4
2
0 control cultiv. hay hay+cult. treatment
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2. Effects of Cultivation Note all legends as for Figure 18 in main text.
Cirsium arvense at Brush Hill Galium verum at Brush Hill
2.5 35 b
30 2 25
2001 2001 1.5 20 2000 2000 1999 1999 1 15 % coverage % 1998 % coverage % 1998 ab 10 0.5 5 a a 0 0 control cultiv. hay hay+cult. control cultiv. hay hay+cult. treatment treatment
Trifolium repens at Brush Hill
40 b 35 30 2001 25 2000 20 a 1999 a 15 a % coverage % 1998 10 5 0 control cultiv. hay hay+cult. treatment
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