Effects of Vegetation Types and Management Modes on Soil Active Carbon, Nitrogen and Carbon Fluxes of Four Forest Tree Species
FANG Xianghua ;HU Wei ;YOU Genbiao;
The study on soil active carbon and nitrogen content and the carbon fluxes of CO_2 and CH_4 is of great significance to the study of forest soil nutrient status and carbon and nitrogen cycle. Taking the 0-20 cm topsoil of four tree species in Fengyang Mountain, Zhejiang,--inus massoniana Lamb, Schima superba, Cyclobalanopsis glauca, and Castanopsis eyrei-as the research objects, the effects of vegetation types and management methods on soil dissolved carbon and nitrogen nutrients, microbial biomass carbon and nitrogen and thecarbon fluxes of CO_2 and CH_4 were compared. The results showed that(1) vegetation type and tree age had important effects on soil C/N ratio and soil moisture content;(2) the change trend of soil inorganic nitrogen content was consistent with pH value, contrary to tree age;(3) the ratio of microbial biomass to nitrogen was significantly affected by soil C/N ratio and soil moisture content;(4) artificial management methods such as applying nitrate fertilizer and long-term continuous cropping will lead to the increase of CH_4 flux. The practice of adjusting soil moisture conditions and pH value and improving management methodsis helpful to reduce forest greenhouse gas emissions.