Soil Respiration And Its Controls In Different Mid-subtropical Evergreen Broadleaved Forest

As forest ecosystems is a large carbon storage library in the terrestrial ecosystem, the evergreen broadleaved forest is of great importance in environmental protection, maintenance the global carbon cycling and human sustainable development. In order to ascertain the variation and controls of the soil respiration in typical ecosystems in the subtropical China, This study has focused on the six natural forest(Castanopsis fabric, Cinnamomum chekiangense, Castanopsis carlesii, Altingia gracilipes, Tsoongiodendron odorum and Cinnamomun micranthum) in Jian'ou of Fujian Province, which are the constructive species of evergreen broadleaved in mid-subtropics of south China.Using the Li- 8100 automated soil CO2 fluxsystem to measure and analyze the soil respiration for a year(2009).The results show that:seasonal variation of soil respiration rate were from 1.13 to 7.72μmol·m-2·s-1 in Cinnamomun micranthum, from 1.59 to 7.4μmol·m-2·s-1 in Tsoongiodendron odorum, from 1.04 to 7.92μmol·m-2·s-1 in Castanopsis fabric, from 1.07 to 8.04μmol·m-2·s-1 in Cinnamomum chekiangense, from 1.55 to 8.48μmol·m-2·s-1 in Castanopsis carlesii, from 1.68 to 8.09μmol·m-2·s-1 in Altingia gracilipes;The relationship of soil temperature with soil respiration is significant function, soil temperature can account for 61.0%-91.4%, while were weakly correlation between soil respiration and soil water content. Soil temperature and soil water content could both explain 61.0%-95.7% changes of soil respiration; The carbon release of soil respiration in six natural forest is 1341.02-1853.83 gC·m-2·a-1, while the Tsoongiodendron odorum soli respiration in the lowest; Through the analysis that the results showed that soil respiration was significantly correlated with fine root biomass(p<0.01), but no linger with soil temperature,soil water content,litter,soil carbon storage and microbial biomass carbon (p<0.05)...