Poluição da água na agricultura

Foreword

Environmental pollution is a major global concern. When sources of water pollution are enumerated, agriculture is, with increasing frequency, listed as a major contributor. As nations make efforts to correct abuses to their water resources, there is a need to determine the causes of water quality degradation and to quantify pollution contributions from many sources. Until such time as adequate facts are made available through research to delineate causes and sources, conflicting opinions continue to flourish and programmes to control and abate pollution will be less effective and efficient in the use of limited resources. Existing knowledge indicates that agricultural operations can contribute to water quality deterioration through the release of several materials into water: sediments, pesticides, animal manures, fertilizers and other sources of inorganic and organic matter. Many of these pollutants reach surface and groundwater resources through widespread runoff and percolation and, hence, are called "non-point" sources of pollution. Identification, quantification and control of non-point pollution remain relatively difficult tasks as compared to those of "point" sources of pollution. FAO's mandate is to raise levels of nutrition and standards of living of people and, in implementing this mandate, it promotes agricultural development and national food security. FAO is equally committed to sustainable development and, hence, has given top priority to sustainable agricultural development. In this context, the Organization recognizes the key role of water in agricultural development and implements a comprehensive Regular Programme on Water Resources Development and Management. One of the thematic areas of this programme is water quality management which includes, among others, the control of water pollution from agricultural activities, with particular reference to non-point sources. It is under the framework of these Regular Programme activities of