Wetlands And Agriculture

This paper reports on a form of multi-criteria analysis that provides a formal approach for evaluating the suitability of a wetland for specific agricultural uses, and ensures that explicit consideration is given to the possible consequences of such utilization. The method is based on a hybrid of ideas taken from concepts and methodologies related to: environmental flow assessments, land suitability classification and the hazard evaluation procedures used in the design of dams. The approach, which elaborates the idea of working wetlands, is generic, though the examples presented are for case studies from southern Africa.

In many places, growing population, in conjunction with efforts to increase food security, is escalating pressure to expand agriculture within wetlands. The environmental impact of wetland agriculture can have profound social and economic repercussions for people dependent on ecosystem services other than those provided directly by agriculture. If wetlands are not used sustainably, the functions which support agriculture, as well as other food security and ecosystem services, are undermined. This report synthesizes findings from multidisciplinary studies conducted into sustainable wetland agriculture by IWMI and partners in Africa and Asia. It highlights the value of wetland agriculture for poverty reduction as well as the need for more systematic planning that takes into account trade-offs in the multiple services that wetlands provide.

Nutrient enrichment of water resources by inputs of nitrogen and phosphorus, which can lead to eutrophication is still a water quality problem in agriculturally dominated watersheds around the world. Internationally, wetlands both constructed and natural are increasingly being used to help reduce both point and non-point source nutrient and contaminant loss from agricultural practices. This publication contains papers presented at the international symposium on "Nutrient Management in Agricultural Watersheds: A Wetlands Solution," which was held during May, 2004 in Wexford, Ireland. The symposium was the result of an international collaboration between the Teagasc Research Centre, Johnstown Castle, Ireland, National Parks and Wildlife, Department of Environment, Heritage and Local Government, Ireland and the Soil and Water Science Department at the University of Florida, Gainesville, USA. These proceedings cover aspects of water quality within agricultural watersheds; management practices to mitigate contaminant and nutrient loss from agriculture; wetland biogeochemistry; wetland functions and values within agricultural dominated landscapes; case studies of wetlands used to retain nutrient and contaminant loss from agriculture; and finally some management and policy issues concerning wetlands are presented. This book provides a good interdisciplinary synthesis of international experiences both in Europe and the USA on the use of wetlands within agricultural watersheds.

This publication is the result of a two-and-a-half-year process that has drawn together critical thinking and practical experience concerning agriculture and wetland interactions. The process began at the Ramsar Conference of Parties (COP) 9 in Uganda, involved a workshop in Wageningen (the Netherlands) in early 2006. This report has been prepared for presentation at the Ramsar COP 10 in the Republic of Korea in October 2008.