Effect Of Artifical Vegetation On The Soil And Water Consevation And The Control Of Phosphorus Loss On The Phosphorous-rich Background Slope

The study site, a phosphorus-rich region which is located in the Damiao country,Xiage town,Chaohu City, is in the upper reaches of the Little Zhegao River. Serious exploration of the region resulted in the formation of a large number of bare areas. Control of soil erosion in this area to reduce phosphorus loss is important to the eutrophication of Chaohu Lake.The soil and water conservation of five different planting patterns were studied in the experiment, including D1(Bare solpes);D2(Cynodon dactylon community); D3(Leapedeza bicolor.Turcz and Indigofera pseudotinctoria Mats community); D4(Leapedeza bicolor.Turcz, Cynodon dactylon and Indigofera pseudotinctoria Mats community); D5(Leapedeza bicolor.Turcz, Cynodon dactylon and Indigofera pseudotinctoria Mats community with the net) in the steep slope(30°), H1(Bare solpes); H2(Cynodon dactylon community) in the gentle slope(10°), bare solpes were used as control,by analyzing changes of vegetation biological characteristics and amount of water and soil loss,the phosphorus loss in runoff plots under natural rainfall.we still studied the change of physical properties and microbial diversity of the soil. The results showed:1. All the vegetation coverages were increased as the times gone.The Cynodon dactylon community coverage was the most as 89% in September. The surface runoff of Bare solpes is 1.4-2.9 times the coverage area of vegetation, the soil erosion of Bare solpes is 3.5-36.5 times the coverage area of vegetation and the phosphorous loss of Bare solpes is 4.5-15.7 times the coverage area of vegetation. The surface runoff and soil erosion under the vegetation coverd were lower than the bare slopes obviously.2. The artifical vegetation could control phosphorous loss,the effect of Leapedeza bicolor.Turcz and Indigofera pseudotinctoria Mats communities were better than Cynodon dactylon community. The phosphorous loss has no significant differences among D3,D4and D5 region.The rainfall intensity has a greater impact on the amount of phosphorous loss in the runoff than rainfall. The fastigium of phosphorous loss lies in july and august in the year. 3. The artifical vegetation improved the soil infiltration rate and reduced surface runoff,especially Leapedeza bicolor. Turcz, Cynodon dactylon and Indigofera pseudotinctoria Mats community.The yearly amount of surface runoff and soil erosion modulus of D4 were 5377.3m3/km2 and 25.4 t/km2·a,and the capabilities of Leapedeza bicolor. Turcz, Cynodon dactylon and Indigofera pseudotinctoria Mats community on water conservation and soil conservation were the most,66% and 97.2%, respectively.4. As times go, The artifical vegetation has increased the soil organic matter content and total soil porosity, reduced soil bulk density and so on, the soil organic matter content has increased by 11.8%-24.7%, bulk density decreased 17.1%-25.7%. As a result, the soil stability has been increased and the soil's capacity of anti-erosion has been strengthened.5. The microbial diversity of the soil between different vegetations has no significant difference. The microbial diversity under vegetation covers are higher than the bare solpe.