[Factors influencing phosphorus loss by runoff process from farmlands in the dianchi watershed].
By laboratory simulated experiment, the effects of soil factors on the farmland phosphorus losses and its concentration were studied under artificial rainfall and nature rainfall. A number of soil and landscape factors were taken into account such as slopeness, soil and plant covers, fertilizers and application performances as well as rainfall intensity. The study showed that the concentration of total phosphorus (TP) and the loss rate varied with slopeness, being highest at slopness of 18 degrees with the values of 0.138 mg.L-1 and 6.14 kg.hm-2. There was no significant difference in TP concentration and the loss rate between under artificial rainfall and under nature rainfall. Moreover, TP concentration in runoff was smaller with the courser soil surface texture, and obviously lower with crop covering than without covering, among which the loss decreased 0.9-2.8 kg.hm-2 at different level of slope. Fertilizer application remarkably enchanced TP concentration and, thus, total phosphorus loss by runoff.
Zhang
Naiming
N
College of Resources & Environment Science, Yunnan Agriculture University, Kunming 650201, China.
Yu
Yang
Y
Hong
Bo
B
Chen
Jianjun
J
D018556:Crops, Agricultural; D005308:Fertilizers; D010758:Phosphorus / Q000032:analysis*; D011891:Rain; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D014872:Water Movements
D005308:Fertilizers; D012987:Soil; D012989:Soil Pollutants; D010758:Phosphorus