ABSTRACT
In order to study the water quality and response to influencing factors in typical watersheds of Three Gorges area between 2004 and 2005, the variation characteristics of nitrate nitrogen concentration were analyzed under heterogeneous landscape condition through continuous observation with method of dividing into sub-watersheds in Quxi watershed (the first-grade branch, located in Three Gorges). The results suggested that nitrate nitrogen concentration fluctuated between 0.4 and 14.6 mg x L(-1) with the highest in winter,higher in autumn and summer and lower in spring. Discrepancy also exists in different years. In addition, nitrate nitrogen concentration shows increasing trends with the aggravating impacts of agricultural activities on environment. Moreover, nitrate nitrogen concentration had some relationships with different land use types and space layout to some extent, and was also affected by geological and hydrological characters in the sub-watersheds, which indicated that response of nitrate nitrogen concentration in water was evident to influencing factors.
