Effects of different subtropical plantations on physical and chemical properties of soil

Impacts of different regeneration tree species on soil fertility in the subtropical forest ecosystems were studied by comparing the physical and chemical properties of soil of Pinus massoniana plantation,Liriodendron chinense plantation,Cunninghamia lanceolata plantation as well as Alnus-Liriodendron mixed plantations with the local natural secondary forests in Dagang Mountains of Jiangxi Province.Results indicated that the soil total porosity: non-capillary porosity and capillary porosity in the 0-20 cm layer all decreased except that of the L. chinense plantation increased.The soil macro nutrient level under all plantations decreased significantly with L. chinense plantation recorded the lowest.There was a sharp decrease both in soil available Fe and Zn,but the available Fe is still sufficient while the available Zn is more insufficient.C.lanceolata plantation improved the level of soil available Cu in both the 0-20 cm and 20-40 cm layers,but the results of other plantations showed an increase in the layer of 0-20 cm and a decrease in the layer of 20-40 cm.