1 Chapter 9: Freshwaters – Openwaters, Wetlands and Floodplains Coordinating Lead Authors: Edward Maltby and Steve Ormerod Lead Authors: Mike Acreman, Martin Blackwell, Isabelle Durance, Mark Everard, Joe Morris and Chris Spray Contributing Authors: Jeremy Biggs, Phil Boon, Bill Brierley, Lee Brown, Alastair Burn, Stewart Clarke, Ian Diack, Catherine Duigan, Michael Dunbar, David Gilvear, Angela Gurnell, Alan Jenkins, Andy Large, Steve Maberly, Brian Moss, Jonathan Newman, Anne Robertson, Martin Ross, John Rowan, Matthew Shepherd, Ann Skinner, Julian Thompson, Ian Vaughan and Rob Ward Key Findings ...........................................................................................................................................................296 9.1 Introduction ......................................................................................................................................................299 9.2 Ecosystem Services from Freshwaters .............................................................................................................303 9.2.1 Provisioning Services .................................................................................................................................................... 304 9.2.2 Regulating Services ...................................................................................................................................................... 309 9.2.3 Supporting Services .......................................................................................................................................................313 9.2.4 Cultural Services ............................................................................................................................................................316 9.3 Freshwater Condition and Trends .................................................................................................................... 317 9.3.1 Status of Freshwaters .....................................................................................................................................................317 9.3.2 Changes in River Dynamics ...........................................................................................................................................318 9.3.3 Condition of Designated Sites .......................................................................................................................................318 9.3.4 Openwaters and Groundwater Monitoring and Assessment in the UK .....................................................................319 9.3.5 Limitations of the Available Trend Data .......................................................................................................................319 9.3.6 Trends for Openwater ................................................................................................................................................... 320 9.3.7 Changes in River Flow Since 1950 ................................................................................................................................ 322 9.3.8 Current General Quality in Rivers ................................................................................................................................ 323 9.3.9 Microbiology and Microbial Quality ............................................................................................................................. 324 9.3.10 Groundwater Status and Trends ................................................................................................................................. 324 9.3.11 Fish Populations ........................................................................................................................................................... 326 9.3.12 Lakes and Standing Waters ........................................................................................................................................ 326 9.3.13 Status and Trends in Ponds ........................................................................................................................................ 327 9.3.14 Status and Trends of Ditches ...................................................................................................................................... 328 9.3.15 Invasive, Non-Native Species ...................................................................................................................................... 329 9.3.16 Climate Change ............................................................................................................................................................ 330 9.3.17 Wetland Extent ............................................................................................................................................................. 331 9.3.18 Wetland Condition and Trends ................................................................................................................................... 332 9.3.19 Trends in Bird Populations .......................................................................................................................................... 334 9.3.20 Land Ownership .......................................................................................................................................................... 336 9.3.21 Environmental Archaeology ....................................................................................................................................... 336 9.3.22 Trends in Ecosystem Services Delivered by Lowland Wetland Priority Habitat Types .......................................... 336 9.4 Drivers of Change .............................................................................................................................................337 9.4.1 Openwaters .................................................................................................................................................................... 337 9.4.2 Wetlands ........................................................................................................................................................................ 337 9.4.3 Floodplains and Flood Risk Management .................................................................................................................... 338 9.5 Trade-offs and Synergies ..................................................................................................................................338 9.6. Sustainable Management ................................................................................................................................340 9.7. Knowledge Gaps...............................................................................................................................................342 9.8 Conclusions ......................................................................................................................................................342 References ..............................................................................................................................................................343 Appendix 9.1 Description of Sources of Data .........................................................................................................354 Appendix 9.2 Current Initiatives .............................................................................................................................355 Appendix 9.3 Summary of Recent Assessments of UK Peatlands ..........................................................................356 Appendix 9.4 Ecosystem Service Delivery for Lowland Wetlands and Trade-off Matrices for Floodplains and Reedbeds ................................................................................................................................357 Appendix 9.5 Approach Used to Assign Certainty Terms to Chapter Key Findings................................................360 Broad Habitats | Chapter 9: Freshwaters – Openwaters, Wetlands and Floodplains 295 Ch 9 Freshwaters.indd 1 19/09/2011 16:58:37 Key Findings* Rivers, lakes, ponds, groundwaters and wetlands provide major services, but 1 well established their benefits are inadequately identified and valued1. This has resulted in habitat losses that are among the fastest in the UK. When managed appropriately, Freshwaters should transport water, matter, energy or organisms within and between terrestrial systems, riparian zones, estuaries and near-coastal waters. They provide: consumptive and non- consumptive uses of water; organisms for food, recreation and conservation; and energy. They can regulate flooding, erosion, sedimentation, local climates and water quality, while facilitating the dilution and disposal of pollutants. They support dispersal through, and resilience in, adjacent ecosystems (for example, though water or nutrient supply), and act as a medium for key biogeochemical cycles. They have large cultural value for recreation, tourism, education, heritage and as inspiration for arts and religion. Costs for people include their role in waterborne diseases and their propensity to flood low-lying infrastructure. Rivers, lakes and wetlands are present throughout UK landscapes. Historically, 1 well established they were highly connected to each other and to their catchments, but are now fragmented and disconnected1. There are more than 389,000 km of rivers in