Nonpoint Source Water Polution in Siera Leone

近来，非点源（ＮＰＳ）水污染在发展中国家日益受到关注．在塞拉里昂，农业和矿业是造成水资源受非点源污染的主要因素．引起水质下降的原因包括土壤的加速侵蚀、农业径流中的氮磷等营养物质和农药等污染物、来自畜牧场的病原菌和酸性矿排水等．由于污染物的转化机理与水力学、地形学、化学反应、土壤类型和土地利用等多因素有关，这使得非点源污染管理变得很复杂．但是，最佳管理措施（ＢＭＰｓ）通过技术、规制和立法等手段能有效地减少非点源污染，ＢＭＰｓ应着重于源的管理而不是污染物的处理

Nonpoint Source Water Pollution in Sierra Leone

Recently, there has been an increasing concern over nonpoint source (NPS) water pollution in developing countries. In Sierra Leone, agriculture and mining have been intrinsically identified as the major sources of these pollution problems on water resources. The major causes responsible for water quality impairment include siltation of rivers and tidal creeks due to accelerating soil erosion, nutrients(primarily nitrogen and phosphorus) and pesticides in agricultural runoff, pathogens from feedlots and mine overburden drained into the river systems. Successful management of NPS is difficult because the pollutant transport mechanisms are complex, as the hydrological, topographic, chemical transport, soil type and land use factors are all significant in determining the applicable control technology to NPS. However, Best Management Practices (BMPs) through technical, regulatory and legislative approaches at cost effectiveness can facilitate the pollution abatement, but emphasis should be placed on source management rather than treatment of the pollutants.