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Understanding the Environmental Effects of Farming on Aquatic Ecosystems - WQ0112

The Water Framework Directive (WFD), which came into force on 22 December 2000, is a wide ranging piece of European environmental legislation that sets ambitious objectives for protecting and enhancing water quality and the status of aquatic ecosystems. Specifically, it aims to achieve “good chemical and ecological status” in all surface waters (rivers, lakes, estuaries and coastal waters) by 2015, where "good" represents a slight deviation from minimally impacted reference conditions. To achieve this, the WFD makes provision for the establishment of River Basin Districts within which river basin management plans will be implemented to target both point and diffuse sources of water pollution.

Farming uses over 76% of the land area of England and Wales and is a major source of water pollution. The main categories of pollutant arising from farming activities are nitrates, phosphates, ammonia, soil sediments, biocides, veteinary medicines, faecal pathogens and organic material. Although some activities can result in point source discharges of pollutants from discrete outlets such as pipes (e.g. accidental spillage of pesticides into drains), the main problem is diffuse pollution, whereby contaminants enter the environment via a multitude of pathways which are dispersed across the catchment.

To develop and deliver cost-effective measures to meet the objectives set out by the WFD, it is vital firstly to assess the contribution of agricultural land management practices in England and Wales to pollutant losses to water and secondly to determine the impact of those pollutants on the ecology of the receiving waters. While some of the impacts of pollution are well documented (e.g. eutrophication), there is a need to pull together information on the effect of the full range of pollutants across all types of aquatic ecosystem. This short desk study will meet this need by exploring and benchmarking current knowledge and understanding of the effects of farming on aquatic ecosystems in England and Wales, and identifying future research needs.

Specifically, the desk study will:

* Identify what data/information already exists, where it resides and how readily available it is.
* Focus on the impact of pollutants/contaminants, including sediments, at the aquatic ecosystem level and on individual species, including vertebrates, invertebrates and algae etc.
* Collate and discuss existing knowledge on suitable indicator species for the effects of pollution/contamination, including those that could act as early warning markers.
* Discuss knowledge on the sources and exposure pathways of potential pollutants, and the relative contribution and effects of different farming management practices, to provide context and background for the study.
* Propose recommendations for future R&D on the effects of farming on aquatic ecosystems, focusing in particular on research which could be used to identify cost-effective mitigation approaches.
* Include a knowledge transfer plan that identies clearly the outputs and pathways to delivery from the proposed project.
Project Documents
• Final Report : Understanding the environmental impacts of farming on aquatic ecosystems   (149k)
• Final Report : Understanding the environmental impacts of farming on aquatic ecosystems   (614k)
• Final Report - Annex : Understanding the environmental impacts of farming on aquatic ecosystems   (324k)
• Final Report - Annex : Understanding the environmental impacts of farming on aquatic ecosystems   (983k)
Time-Scale and Cost
From: 2007

To: 2007

Cost: £38,705
Contractor / Funded Organisations
WRc plc
Ecosystem Functioning              
Sustainable Farming and Food              
Sustainable Farming and Food Science              
Water Framework Directive              
Water Quality              
Water Quality and Use              
Fields of Study
Water Quality