为了从流域尺度了解滇池流域土壤氮、磷的水平分布特征,本研究根据不同的土地利用方式,在滇池流域选择130个样点进行表层土壤pH、氮、磷和有机质的测定.结果表明,水平分布呈现为滇池东部盆地区的斗南、马金铺、晋城主要农耕区及西山片区全氮含量较高；北部松花坝、东北部宝象河及南部的山地区全氮含量较低.其中斗南片区土壤氮的含量最高,为2.21 g kg-l;宝象河片区最低,为1.32 g kg-1.土壤全磷水平分布为南部上蒜和东部马金铺、斗南、晋城较高；西山、东大河次之；北部松花坝和东北部宝象河最低.其中上蒜片区最高,含量为2.21 g kg-1;宝象河片区最低,为0.80 g kg-1.大量化肥投入导致污染物氮、磷高积累的大棚种植区和湖滨坝平地成为滇池农业面源污染的高潜力区.因此,有必要重点加强对大棚种植区、湖滨区和坝平地农业面源污染的防控.%In order to understand distribution characteristics of soil nitrogen and phosphorus in the Dianchi watershed at the watershed scale, soil pH, total nitrogen (TN) , total phosphorus (TP) , and soil organic matter were analyzed of 130 surface soil samples collected from lands different in land-use type in the Dianchi Basin. Results show that the soils in the major fanning regions including Dounan, Majingpu and Jincheng in the basin east to Lake Dianchi and some of Xis-han, were higher in total N, and those in Songhuaba in the north, Baoxiang River area in the northeast, and the mountains in the south of the watershed were lower. The highest and the lowest TN content was found in Dounan (2. 21 g kg-1) and Baoxiang River area (1. 32 g kg-1 ) , respectively. And the soils in Shangsuan in the south and Ma-jingpu, Dounan and Jincheng in the east of the watershed were the highest in total P, and followed by those in Xishan are Dongda River area, and those in Songhuaba in the north and Baoxiang River area in the northeast the lowest. The highest and lowest content of TP was found in Shangsuan (2. 21 g kg-1) and Baoxiang River area (0. 80 g kg-1) , respectively. The findings suggest that in the greenhouse fanning dominated regions, lakeside plains and flat tablelands, the application of large volumes of chemical fertilizers has led to high accumulation of N and P in the soil, thus making these areas highly potential non-point source agricultural pollution sources. It is, therefore, necessary to intensify control and management of non-point source pollution in those areas.
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