中文摘要：

基于三峡库区自然降雨条件下3个连续雨季观测的径流试验数据,分析不同试验处理下坡耕地地表径流磷浓度及构成,探讨地表径流磷流失量的时间变化过程及分布差异。结果表明：颗粒态磷占磷流失总磷的70%以上,是地表径流磷流失的主要形式,5～6月磷流失量达到峰值;不施肥处理小区磷流失量最高,横坡垄作小区磷流失量最低;三峡库区增加地表植被覆盖程度能够有效减少坡耕地地表径流磷流失量,减缓种植业面源污染对地表水体产生的潜在富营养化威胁。

英文摘要：

Using the ＂Winter Wheal-Summer Maize＂ model and the plot runf moniloring method, we sludied file thaaterislies of nitrogen and phosphorus loss in the soil sedimenl of purple sloping filrmland under five conditions, inluding cmtrol, combined manure/fertilizer alplicaion, chemical fertilizer, high intensity hemical fertilizer, and cross ridge farming. The resuhs shwed thai the nutrient content of the surface soil increased, to some exlent. urthermqre, Iht intlrienls were tithed in the sediment for all groups. The degree of sedimenl nutrient enrichment of chess ridge larming was less great ompared lt longitudinal farming. For the combined manure/fertilizer application, the ralio of effective nutrients was larger than that of total nutrients; whereas, for the chemical tertilizer group, the ,＇atio of effective nutrients was significanlly smaller. At all tertilization levels, sediment loss only accounted for 0.34% - 6.21%. 78.80%- 84.83% of the total phosphorus loss. occurred in the sediment, and the phosphorus loss was largely in the sediment. The relative loss factor of nitrogen was the largest for the cheroical ferlilizer group, followed by the cross ridge farming group, the high intensity chemical firlilizer group, and the combined manurefrtilizer applieation group. The relalive loss faclor of thosphorus was the largesl for the high intensity chemical fertilizer group, followed by the cross ridge farming group, the chemical ferlilizer group, and the combined manure/fertilizer applieation group.