Agriculture and Karst

Abstract

This chapter provides a review of the impacts of agriculture on karst terranes, and on management approaches to minimize such impacts. It discusses the range of agricultural activities with potential impacts on soil and water in karst regions, including deforestation, changes in grazing intensity and changes from pasture to tillage, application of fertilizers, and pesticides and storage of farm wastes. Case studies of impacts on soil and on water quantity and quality are presented, with a particular focus on water quality issues including suspended sediment, nitrate, phosphorus, pesticides, and microbial pathogens. The particular vulnerability of karst regions to such impacts is discussed, including the occurrence of point recharge in closed depressions and swallow holes, the thin, patchy soil cover found in many karst areas, the presence of epikarst and the occurrence of conduit flow within karst aquifers. Methods of risk evaluation are reviewed briefly and management strategies to minimize impacts of agriculture are discussed, including the use of Best Management Practices, community-based agri-environmental initiatives, and various legislative controls.