Study On The Relationship Between Plant Species Diversity And Physicochemical Property Of Soil In Subalpine Coniferous In Western Sichuan

Subalpine in western Sichuan is the main part of southwestern forest zone, which is the secondary in China. Meanwhile, it is also the important Implementation Area of the Natural Forest Protection Project and Key area of "Ecological barrier" in the Yangtze River. Dealing with removal of Herb layer,Shrub layer in plot, we compare the influence of the plant species diversity change to physicochemical property of soil among each paralleled and Before-and-after dealing. So that this study could reveal the further relationship between plant species diversity and physicochemical property of soil.This experimentation surveys the plant Community of mixed artificial spruce-Betula forest and artificial spruce pure forest, which is so similar in natural Geography, in Subalpine of Sichuan Bi Peng Gou. And we remove the Herb laye,Shrub layer in the control test. We adopt relevant analysis and stepwise multiple regression analysis in order to reveal the correlation between plant species diversity and physicochemical property of soil, basing on the wild plot survey and data analysis inside.(1)Comparing 1,2,3 spruce mixed forest, the index of species diversity is Herbs>trees>Shrubs. Comparing 4,5,6 spruce pure forest, the index of species diversity is Herbs>Shrubs>trees.(2)According to the stepwise multiple regression analysis between plant species diversity and physicochemical property of soil in each plot:The number of species in trees of spruce forest is obvious negative correlation with total phosphorus; The Shannon-Wiener index is obvious negative correlation with total kalium; The Margalef index is obvious positive correlation with available phosphorus and total kalium; The dominance index is positive correlation with total kalium. The number of species in shrubs is obvious positive correlation with total nitrogen; The Shannon-Wiener index is obvious positive correlation with pH, Total nitrogen and rapid available potassium; The Pielou uniformity index is obvious negative correlation with total porosity; The Margalef index is obvious positive correlation with total nitrogen and rapid available potassium; The dominance index is obvious negative correlation with total nitrogen; The number of species in herbs is obvious negative correlation with total kalium; The Shannon-Wiener and Pielou index are negative correlation with total nitrogen; The dominance C is obvious positive correlation with total nitrogen.(3)This study reveals that:The Water content in spruce mixed forest is greater than spruce pure forest; The Apparent density in spruce mixed forest is less than spruce pure forest; The Capillary water, Saturation water, total porosity, organic matters, total nitrogen, hydrolyzable nitrogen in spruce mixed forest is greater than spruce pure forest; The pH, total phosphorus, available phosphorus, total kalium, rapid available potassium in spruce mixed forest is less than spruce pure forest.(4)In control test after two years, the diversity index H', Jsw, dMa C of plot 2 all go down. The diversity index H', Jsw, dMa C of plot 3 are the same as plot 2.(5) In control test after two years, the pH and total nitrogen in plot 2 and 3 go down, but the hydrolyzable nitrogen, available phosphorus and rapid available potassium go up.(6)In control test from July,2007 to August,2009, it reveals that the pH, total phosphorus of RH and RS go down as time goes by, but the hydrolyzable nitrogen, available phosphorus and rapid available potassium go up.