Influence Of Water Conservation Forest In Region Of Xiquanyan Reservoir On Water Quality

The influence of water conservation forest on water quality has been studied. The hiberarchy include rainfall, throughfall, stemflow, litterthrough and runoff. The water quality of runoff in different forest, headwaters of Ashi river and Xiquanyan reservoir has been analysed and evaluated. The results show that the content of Do in runoff of Coniferous mixed forest is lowest and that of Betula costata is highest. The content of NH3-N of Coniferous mixed forest is higher than rainfall and other forest. The content of NH3-N of Corylus cornuta marsh is lowest. The purgative effect of NH3-N of Larix gmelinii plantation is better too. The content of total nitrogen and total phosphorus in every forest runoff is higher than rainfall, and that of Coniferous mixed forest is the highest. The content of Zn in runoff of Pinus koraiensis plantation(H-3),Corylus cornuta marsh and Picea asperata plantation is lower than rainfall, and the content of Zn in Pinus koraiensis plantation (H-3) is the lowest. The content of Cu and F of every forest runoff is higher than rainfall. Generally compared, the water quality of Pinus koraiensis plantation (H-3) runoff is the best, that of Corylus cornuta marsh is better and that of Coniferous mixed forest is worst. The temporal diversification of total nitrogen is consistent in the brook and river. And the content of total nitrogen in the river is higher than that in the brook every month. The content of COND, TDS, Ca and total phosphorus in the river is higher than that in the brook every month. The content of Do is high in the brook and river every month. The temporal diversification of Na, Mg and Zn is consistent in the brook and river. The general evaluation of brook water quality belong to II. It suits to be as the wellhead of subsistence water and the habitat of aquatic animal and plant. The general evaluation of river water quality belong to IV. It can be used by industry and amusement. The water quality of Xiquanyan reservoir entrance is the worst and that of exit is the best in the period of absence of water. The water quality of reservoir center is better than the reservoir entrance and exit in the period of abundance of water. The general evaluation of water quality belong to IV in the period of absence of water. It can be used by industry and amusement. The general evaluation of water quality belong to V in the period of abundance of water. It can be only used by agriculture and landscaping.