Phosphorus Loss from Dry Sloping Lands of Three Gorges Reservoir Area, China  

作　　者：HU Zheng-Feng GAO Ming XIE De-Ti WANG Zi-Fang 

机构地区：[1]College of Resources & Environment, Southwest University [2]Chongqing Municipal Environmental Protection Bureau

出　　处：《Pedosphere》2013年第3期385-394,共10页土壤圈（英文版）

基　　金：Supported by the National Key Technologies Research and Development Program of the Ministry of Science and Technology of China during the 12th Five-Year Plan Period (No. 2012BAD141318)

摘　　要：Eutrophication in the Three Gorges Reservoir has become a serious issue, and phosphorus (P) is the nutrient thought to be primarily responsible although there are few studies about P loss from the mostly sloping farmlands of the area. This work investigated the amounts and forms of P loss from 9 farmlands with the slopes of 4°, 9°, and 17° in a small watershed, Wangjiagou in Fuling District, Chongqing of China. The slope of the relationship between runoff and rainfall increased with field slope; i.e., there was a significant interaction between the effects of rainfall and field slope on water export. For sediment export by surface runoff, there was no interaction between field slope and rainfall, and the intercept of the relationship between rainfall and sediment loss was significantly different for the 3 slopes. The main P loss was from sediments, regardless of slope. In the runoff water, particulate P was the largest P fraction, and its loss was greatest from the steepest land and least from the flattest. The release of total P and available P from sediments followed the same trend. The P loss during May to July in Wangjiagou was more than 60% of the annual total.Eutrophication in the Three Gorges Reservoir has become a serious issue, and phosphorus （P） is the nutrient thought to be primarily responsible although there are few studies about P loss from the mostly sloping farmlands of the area. This work investigated the amounts and forms of P loss from 9 farmlands with the slopes of 4°, 9°, and 17° in a small watershed, Wangjiagou in Fuling District, Chongqing of China. The slope of the relationship between runoff and rainfall increased with field slope; i.e., there was a significant interaction between the effects of rainfall and field slope on water export. For sediment export by surface runoff, there was no interaction between field slope and rainfall, and the intercept of the relationship between rainfall and sediment loss was significantly different for the 3 slopes. The main P loss was from sediments, regardless of slope. In the runoff water, particulate P was the largest P fraction, and its loss was greatest from the steepest land and least from the flattest. The release of total P and available P from sediments followed the same trend. The P loss during May to July in Wangjiagou was more than 60% of the annual total.

关 键 词：agricultural production area EROSION nutrient loss purple soil soil loss 

分 类 号：S153[农业科学—土壤学]