Effects of forest type, stand age, and altitude on soil respiration in subtropical forests of China

Abstract

An automated chamber system was used to study how soil respiration (RS) differed with stand age (SA), altitude (AL), and forest type (FT), in subtropical China. From 2006 to 2008, measurements of soil-surface CO2 efflux and associated environmental factors were made in an evergreen broad-leaved forest (EB), and five aged Chinese fir [Cunninghamia lanceolata Hook.] plantations (CF), and three altitudinal Moso bamboo [Phyllostachys pubescens Mazel ex J. Houz.] plantations (MB), in Dagangshan mountain range, Jiangxi Province. Multivariate analysis of covariance with soil temperature (T) and soil water content (SWC) as the covariates showed that FT and AL as the independent factors had a significant effect on RS (P<0.01, P<0.05, respectively). The RS in the CF differed significantly from EB and MB (P< 0.001), but not between EB and MB. The RS was positively correlated with T, and responded to changes in SWC at higher Ts. The correlation between RS and SWC was improved when the RS was normalized to 10°C. Annual mean RS differed significantly with SA and were ranked in the order (from high to low) of 21-25, 26-35, 11-20, >36, and 1-10 years. The conclusion of this study is that T, SWC, AL, FT, and SA all have significant effects on RS in subtropical China. © 2011 Taylor & Francis.