Ecological Mechanisms of the Effects of Vegetation Restoration on the Controls of Non-Point Source Pollution on Barren Tableland in Dianchi Watershed of China
滇池流域荒台地植被恢复工程控制面源污染生态机理

Surface runoff,soil erosion and the leaching of the different forms of nitrogen and phosphorus were observed and the hygroscopic volume of branch and leaves of all plant species and soil penetration were determined to understand the ecological mechanisms of the effects of vegetation restoration on the controls of non-point source pollution on barren tableland in Dianchi Watershed of China.Results indicated that there were significantly relationships between surface runoff volume and the output of non-point pollution matters.The different manmade vegetation systems,consisted respectively of A.nepalensis,A.mearnsii,R.pseudoacacia and V.zizanioides clump,had shown the different potentials to control the leaching of TN,TP,soluble TP,soluble TN.Strong hygroscopic functions of leaves and branch was able to promote the interception of rainfalls and give rise to the less of surface runoff.The leaves,that were small,with low water content,no leathery and have rough face and epidermal wools,were able to got the highly ratio of the hygroscopic volume to aboveground fresh standing crops and strengthened the interception of forest canopy.Preparing soil,growth of root system of plant and the natural recovery of vegetation at the gap of trees enhanced surface runoff penetration,as lightened the surface runoff leaching the different forms of nitrogen,phosphorus of soil on the stands.The leaching of different forms of nitrogen and phosphorus went down with the controls of surface runoff in different stands as well.