Study on the characteristics of phosphorus loss and the vegetation restoration measures in the phosphorus-enriched degraded mountain area in the Dianchi lake watershed, southwestern China

摘要

The paper aims at figuring out the characteristic of phosphorus loss from different vegetations in the phosphorus-mining area of Dianchi lake watershed. We analyzed the concentrations of TP and AP in soils sampled from the study area in various seasons; both quantity and quality of runoff were also monitored. For controlling phosphorus loss, we established 9 study sites categories by different vegetations. According to the monitored data, the content of TP in soils ranged from 1.56 to 80.2 g/kg. The total P content in runoff is 104 土 38.1 mg/L. The concentration of dissolved phosphorus in runoffis 1.01 ± 0.372 mg/kg,accounting fo?3.33% of total phosphorus. In the phosphorus-enriched degraded mountain area, the soil P content is high and easy to be transported by runoff. There is a significant negative correlation between the runoff coefficient and the vegetation coverage, and the correlation coefficient is -0.837. There is also a significant negative correlation between runoff coefficient and plant community of litter layer coverage, and the correlation coefficient is -0.810. Therefore, the key to controlling phosphorus loss is to improve the coverage of vegetation and litter. The findings will be advantageous for controlling phosphorus loss.