Effect of Tropical Mountain Rainforest Ecosystem on Water Quality of Precipitation

Based on measuring of elements contents for rock,soil and hydrochemistry flow since 1995 in Jianfengling tropical mountain rainforest, concentration values of COD,NH4+-N,phenol,Zn,Cu,Pb,Cd,Ni in precipitation and total runoff for two rainforest watershed were more low than that of the first standard of area water environment. Main consisting of the rock belongs to the potash feldspar in which content of Zn,Mn and Pb is high relatively for measuring of 8-weight metal. Elements migrating of rock in water is main chemistry effloresce with dissolve,hydrolyze and combustion in the system. Concentration content of COD,NH4+-N,phenol,Zn,As,Cd and Ni in rainfall was decreased range from32% to 82% by the canopy layer.The soil layer could bring the absorb effect on COD,Cu,Zn,Mn,Fe by net rainfall.The rainforest system could store contents of COD,NH4+-N,phenol,Cu,Zn,Cd and Fe by rainfall input of 44.4%,23.7%,40.2%,8.9%,57.0%,27.7%,88.3% respectively.The tropical mountain rainforest ecosystem has a marked purify function of water quality.