Biodiversity Impacts at Various Scales Following Conservation Management of Synanthropic Sites in North West England
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Biodiversity impacts at various scales following conservation management of synanthropic sites in North West England. Mark Champion BSc. (Hons), MSc. PGCert. This thesis is submitted to Edge Hill University in partial fulfilment for the degree of Doctor of Philosophy June 2018 Table of Contents Table of Figures 2 Table of Tables 3 Acknowledgements 5 Biodiversity impacts at various scales following Abstract conservation management of synanthropic sites in 6 North West England. Acronyms Table of acronyms and abbreviations. 8 Chapter 1 Introduction 9 Chapter 2 Reedbed conservation on a landscape scale 30 Chapter 3 Hay cutting and Rhinanthus minor redirect meadow 79 creation in a synanthropic Nature Reserve. Chapter 4 The habitat preferences of Willow Tit in Britain in a 115 landscape with a stable population. Systematics and conservation of Dactylorhiza. Chapter 5 (Orchidaceae) on synanthropic sites in the 139 Northwest of England. Chapter 6 Summary 178 1 Page Figure Table of Figures number Chapter 1 Figure 1.1 Map of the Wigan Flashes. 11 Figure 1.2 Map of Greenheart regional park. 13 Figure 1.3 Map of Great Manchester Wetlands NIA area. 13 Chapter 2 33 Figure 2.1 Distribution of reedbeds in Great Manchester Wetlands NIA. Key to reedbed and fen sites across Great Manchester Wetlands 36 Figure 2.2 NIA. Chapter 3 82 Figure 3.1 Map of locations of meadows created on synanthropic land. Bar graphs showing soil organic content, pH and mean metallic ion Figure 3.2 92 content. Figure 3.3 Bar graph of mean Potassium, Zinc and Lead content. 93 PCA based upon metal ion composition, pH and organic content of Figure 3.4 94 soil in top 30 cm. PCA based upon metal ion composition, pH and organic content of Figure 3.5 95 soil in all sampled soil layers. NMDS ordinations of Hellinger transformed percentage cover data Figure 3.6 96 and frequencies of species for each year surveyed. Figure 3.7 Bar graph of species richness. 98 Bar graph of mean Shannon diversity values by sampling for all Figure 3.8 99 sampled years. Figure 3.9 Bar graph of mean Shannon diversity values of grass-like species. 99 Figure 3.10 Bar graph of mean Shannon diversity values of forbs. 100 Bar graph of frequency of MG5 and non-MG5 species by sampling Figure 3.11 101 year. Chapter 4 Figure 4.1 Map showing area studied in Northwest England. 120 Figure 4.2 GIS analysis of Willow Tit records. 121 CCA of woodland bird associations with measured physical Figure 4.3 126 factors. CCA of woodland bird associations with secondary scrub tree Figure 4.4 128 species. Figure 4.5 Primary canopy tree diameter at all survey points. 129 Figure 4.6 Secondary scrub tree diameter at all survey points. 129 2 Page Figure Table of Figures number Chapter 5 150 Figure 5.1 Map survey locations across the UK. 153 Figure 5.2 Diagram showing measurements of Dactylorhiza plant taken. PCA comparing D. purpurella and D. praetermissa using seven 159 Figure 5.3 variables. PCA of D. purpurella, D. praetermissa and the research 161 Figure 5.4 population of Wigan Marsh Orchids using eight variables. PCA of D. purpurella, D. praetermissa and Wigan Marsh Orchid 163 Figure 5.5 comparing differences at each surveyed site. 3 Table Table of Tables Page Chapter 1 Protected sites in the Great Manchester Wetlands NIA and their 15 - Table 1.1 designations. 21 Total habitat measurement by type in Great Manchester Wetlands 23 Table 1.2 NIA. Chapter 2 Name, location, area and distance to nearest reedbed site for 34-35 Reedbed and reed fen sites in the Great Manchester Wetlands Table 2.1 NIA. Minimum Habitat requirement and dispersal distance for each 38-47 Table 2.2 reedbed specialist. 49-64 Table 2.3 Taxa mobility between reedbeds. Chapter 3 Composition by weight of the original commercial meadow seed 86 Table 3.1 mix. 97 Table 3.2 Changes in NVC affinity of surveyed meadows using MAVIS. Chapter 4 Table 4.1 Characteristics of woodlands in Wigan study area. 125 127 Table 4.2 Trees recorded in Willow Tit survey areas. Chapter 5 144 Table 5.1 Dactylorhiza species and ploidy level in the British Isles. 149 Table 5.2 Summary of 11 survey sites. Vegetative and floral characters collected from Dactylorhiza 152 Table 5.3 individuals. ANOVA for character differences between Wigan and Bolton 157 Table 5.4 research Marsh Orchids. Character comparison between known D. purpurella 158 Table 5.5 and D. praetermissa using ANOVA. ANOVA test investigating the measured characters for potential 160 Table 5.6 hybrid Wigan Marsh Orchid populations. Character comparison between known populations of Dactylorhiza 161 Table 5.7 species using ANOVA. Dactylorhiza praetermissa and Wigan Cemetery Marsh Orchid 166 Table 5.8 character comparison ANOVA results 4 Acknowledgements This work has been a long time in preparation and has run in parallel with my everyday work at the Flashes, while at the same time being part of my life outside of work. Sometimes I couldn't tell the difference! The unstinting support throughout of Patricia Rigg, whom acted as secretary on many field trips and offered help throughout is hereby recognised. I would also like to thank the many Lancashire Wildlife Trust staff who have assisted as the work developed, notably Anthony De Silva for helping to produce the maps and Nectar Creative for advice on graphic design while Roy Champion helped to locate good orchid sites in southern England. I am grateful to Wigan Council, The Lancashire Wildlife Trust, Hampshire Wildlife Trust and Natural England for allowing access to their sites. I would like to add my heartfelt thanks to the Biology Department at Edge Hill University. It has been a good place to be a student. In particular, I would like to thank Dr Elizabeth Sullivan and Dr Mary Dean who were always there to help, Dr Ian Powell who was supportive throughout (even when I tried his patience!) and Prof Paul Ashton who has supported my career generally (I knew him when he was a humble Dr!). In the later stages of the work, I would like to thank Rebecca Whitla for help with the literature searches, Dr. Carl Barker for help with the soil PCA plot and Katherine Judson for proof reading and formatting and Graham Stelfox for help with reference lists in Chapter 2. 5 Mark Champion Presented for the degree of Doctor of Philosophy Biodiversity impacts at various scales following conservation management of synanthropic sites in North West England. Abstract Large areas of ex-industrial land remained following the decline and abandonment of heavy industries from the 1960s onwards. While most sites were developed, a few escaped significant modification and succession upon nutrient poor soils produced species-rich plant and invertebrate assemblages. One of the largest such sites is the Wigan Flashes area in North West England which now comprises part of the 1500ha Wigan Greenheart. This contains a variety of habitats including open water, extensive reed beds, grasslands scrub and woodland. It is also home to several rare species. In the last two decades, work has been undertaken to improve the conservation value of these habitats. This thesis addresses a number of questions assessing the contribution that synanthropic sites can make to nature conservation. Within the last eighteen years, conservation work in the Wigan Greenheart area has progressed from single site-based projects to a landscape scale-approach. In the first chapter, the potential of this approach is explored by assessing to what extent the separate reedbed habitats within the area are functioning as a single unit based upon the dispersal distances and breeding area requirements of reedbed specialist species. This showed that for many vertebrates the reedbeds may function as a unit, however for the invertebrates not enough is known of the ecological requirements and dispersal capacity to determine whether the habitats function as a network. The second study investigates the success of management interventions in a twenty-year grassland creation project. By targeting the management and steering the grassland development by the addition of Yellow Rattle, Rhinanthus minor L., the meadows have 6 developed into recognisable plant communities, comparable to vegetation described for long established grasslands managed in a similar manner. The third study assesses the importance of secondary woodland for the fast-declining Willow Tit (Poecile montanus Conrad von Baldenstein, 1827). The connectivity provided by the network of scrub habitats and secondary woodlands is a key factor in the continued success of Willow Tit in the area. The final chapter explores the evolutionary dynamics of such disturbed sites. Utilising a morphometric approach an assessment of the marsh orchid (Dactylorrhiza spp.) populations was undertaken. This revealed extensive hybridisation between southern and northern marsh orchids (Dactylorrhiza praetermissa (Druce) Soó and Dactylorrhiza purpurella (T and T.A. Stephenson) Soó) on the ex-industrial habitats within the narrow contact zone between these two species, thus revealing the dynamic evolutionary processes at play in these habitats. Hybridization is a method by which genes are transferred from one species to another typically between closely related species. This potential source of genetic novelty may be an important source of variation and allow plants in novel habitats or changing environments to adapt to their conditions. The thesis has provided evidence that the management of these synanthropic sites can provide nationally important conservation outcomes over a 16-year time-scale, benefiting a range of habitats, species and communities. The development of the reedbeds and the meadows demonstrates the capacity of the post-industrial landscape to support communities of conservation value. 7 Refer to Table 1 for acronyms and abbreviations used throughout this thesis Table 1.