IMPACTS OF IRRIGATED AGRICULTURE ON WATER RESOURCES IN INDONESIA

Abstract

Agriculture, like many other activities, can have positive and negative impacts on the environment and on water resources in particular, with consequences for human health as well as the environment. On the other hand, the use of water resources by agriculture can cause quantitative resources depletion and qualitative deterioration due to overuse or misuse. Many types of compounds that can contaminate soil and water resources are those which are most closely associated with agriculture practices. A part from those pollution phenomena deriving from intensive livestock rearing that produce wastes (liquid manure in particular) that could be described as point sources, the emissions of pollutants from agricultural fields are in general defined as diffuse sources (or non-point) sources. Two main categories of pollutans should be dealt with the examining the pollution of water resources from agricultural sources viz nutriens and pesticides. Nutrients are mineral or organic compounds containing mainly nitrogen, phosporus or potassium that occure in the soils and water through natural processes (animal mannure, microbial breakdown of organic matter) and through human activities or human controlled land use practices (application of fertilizers, sewage releases, soil cultivation, livestock production).