对云南省抚仙湖尖山河小流域降雨量以及坡耕地、梯坪地、灌草丛、人工林和次生林5种土地类型及村庄和道路等非生产用地产生的地表径流量和泥沙量进行了定位观测,并对地表径流和泥沙中所含面源污染物进行了测定.结果表明:①6~10月份是该流域出现较大阵雨的主要时期,2006年6~10月份降雨量占全年降雨总量的83.2%,这一时期是产生水土流失和面源污染的主要时期.②坡耕地和人工林是地表径流和泥沙产生的主要场所.坡耕地的地表径流和泥沙产生量分别占小流域产生总量的22.97%和62.96%,人工林的地表径流和泥沙产生量分别占小流域产生总量的34.69%和16.76%.③尖山河小流域面源污染物主要来源于坡耕地和人工林.在坡耕地和人工林,随地表径流产生的面源污染物TN、TP和COD分别占流域产生总量的75.01%、51.63%和66.42%,随泥沙产生的TN、TP和有机质分别占流域产生总量的74.12%、73.18%和62.14%.④村庄和道路等非生产用地单位面积的面源污染物产生量较高,但由于总面积较小,在流域面源污染物产生总量中的比例很小,TN和TP分别只占产生总量的3.98%和1.05%.在流域中所占面积很少的坡耕地(仅占7%)却成了面源污染产生的主要场所.
This research was undertaken in the Jianshan River watershed of Fuxian Lake, Yunnan Province to analyze the contribution of non-point source pollution to the watershed from different land use types, and to put forward control countermeasures for the non-point source pollution. Surface runoff and sediment were determined, and non-point source pollutants were tested in sloped farmland, terraces, shrub land, grass land, artificial forest, natural secondary forest, villages and roads. Heavy showers occur mainly from June to October each year, and in 2006 the rainfall from June to October accounted for 83.2% of the total rainfall. This period was the key to the erosion of water and soil, and the production of non-point source pollution. Sloped farmland and artificial forests were the main sources of surface runoff. Surface runoff and sediment from sloped farmland accounted for 22.97% and 62.96% of the total amount of the totals in the watershed, respectively, while runoff and sediment losses from artificial forest accounted for 34.69% and 16.76%. Therefore, in the Jianshan River watershed, non-point source pollution came mainly from sloped farmland and artificial forest. In both sloped farmland and artificial forest, TN, TP and COD of surface runoff accounted for 75.01% , 51.63% and 66.42% of the total amount in the watershed, respectively, whilst TN, TP and organic matter of sediment accounted for 74.12% , 73.18% and 62.14% of the total amount. In villages and on roads, the production of non-point source pollution was less, because the area was smaller, although the production of non-polnt source pollutant was high per unit area. TN and TP of villages and roads accounted for 3.98% and 1.05% of the total amount in the watershed, respectively. In general, sloped farmland was the main source of non-point source pollution, although its area was only 7% of the total area.