中文摘要：

为了解三峡库区农业施肥对水质的影响，通过划分子流域和设置作用区的方法，对张家冲小流域的施肥状况、水体氮含量及其形态进行了调查分析.结果表明，在不同尺度上农户的施氮量有很大的差异，化学氮肥占总施肥量的90%以上.流域水体中TN含量〉2.50mg/L，主要以NO3^--N的形态存在.在不同尺度范围内水体氮素含量和施氮量之间的相关性表现出很大差异.水体氮含量与其上游200m内的总施氮量和子流域的平均施氮量之间显著相关.

英文摘要：

For understanding the influence of agricultural fertilizer on water quality in Three Gorges reservoir area, the fertilization condition, the nitrogen content and its forms in water body of Zhangjiachong watershed were investigated and analyzed through the methods of dividing sub-watersheds and setting up action zones. Nitrogen application amount of agriculturists on different scales had very great difference, the chemical nitrogen fertilizer occupied above 90% of total fertilization amount, TN content in water body of watershed was more than 2.50mg/L, existing mainly the form of NO3^--N. In different scale ranges, the relation between nitrogen content and nitrogen application amount appeared very great difference. Among the water body nitrogen content and the average nitrogen application amount sub-watersheds or the total nitrogen application amount in 200m of its upper reached,the relations were marked.