滇池流域人工模拟降雨条件下农田施用有机肥对磷素流失的影响

应用田间原位人工模拟降雨的方法，在滇池流域不同作物类型农田上研究了有机肥（猪粪）不同用量水平对农田磷素流失的影响。结果显示，随着有机肥（猪粪）施用量的增加，农田流失液中各形态磷素的平均浓度提高，两者间呈显著正相关，相关系数均达到0..9以上。径流方式下，颗粒态磷是主要流失形态；渗漏方式下，有机肥用量水平低时颗粒态磷是主要流失形态，有机肥用量达到中等至较高水平时水溶性是流失的主要形态。同一有机肥用量水平下，不同作物类型农田流失液中各形态磷素的平均浓度均表现为:蔬菜田花卉田粮田。

Effects of swine manure application on P losses from different farmlands under simulated rainfall in Dianchi watershed of Yunnan province

Field in-situ trials were carried out to study the effects of swine manure application on phosphorous losses from different farmlands under rainfall simulation in Dianchi watershed of Yunnan province.The results show that with the in- crease of applying swine manure amounts,concentrations of various phosphorus forms in runoff water from farmland are increased.The average concentrations of run off phosphorus are highly correlated(correlation coefficients>0.9)with the manure application rates.Particulate phosphorus is the main form in runoff water.Particulate phosphorus is also the main form in leaching water when the manure application rate is low,while dissolved phosphorus is the main form in leaching water when the manure rate is from middle to high.Under the same level of swine manure application,concen- trations of various phosphorus forms in runoff water from different farmlands have the same trend:vegetable field>flower field>cropland.