Nitrogen and phosphorus losses by runoff erosion: Field data monitored under natural rainfall in Three Gorges Reservoir Area, China

作者：Ma, Xiao^*; Li, Ye^*; Li, Bolin; Han, Weiyi; Liu, Dongbin; Gan, Xiaoze

来源：Catena, 2016, 147: 797-808.

DOI：10.1016/j.catena.2016.09.004

• Agricultural non-point source
• Runoff
• Natural rainfall
• Three Gorges Reservoir Area
• Nitrogen
• Phosphorus

Nitrogen (N) and phosphorous (P) from agricultural non-point source (ANPS) pollution are the great threats to the regional water quality in the Three Gorges Reservoir Area (TGRA) of China. To explore the pollution of N and P loss from the sloping land in TGRA agricultural areas, field-scale plot experiment under natural rainfall was conducted from May 1 to October 31 in 2012. We monitored and analyzed rainfall, runoff volume, sediment yield, and nutrient concentration under different conditions (3 soil types, 3 surface slopes, and 5 cropping systems) in 30 experimental plots of 20 m(2) during the rainy season. The results indicated that average loss ratio of N was 1.90%, while that of P was 1.54%. N and P loss ratios from surface runoff in 15 plots of sloping farmland were the highest Purple soil (PS) was the most severe soil and nutrient loss. Within all the 5 cropping systems, the loss ratios of N and P from intercropping of citrus and grass (C-G) were the lowest. The practice of C-G, which was the most beneficial cropping system, should be further encouraged especially in TGRA to cope with the serious issues of N and P losses. These findings provide useful and valuable information for decision makers and planners to take sustainable measures for the control of ANPS pollution in TGRA, and are beneficial for the agro-ecological environment management of the local agricultural watersheds.

• 出版日期2016-12
• 单位湖北师范大学; 武汉理工大学