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研究轻度干扰和重度干扰对亚热带米槠人促更新林土壤总呼吸、异养呼吸的影响.结果表明:与轻度干扰米槠林相比,重度干扰林的土壤呼吸及其各组分均下降,其中,自养呼吸(R_A,1.75 t C·hm~(-2)·a~(-1))下降了40%.与轻度干扰林相比,重度干扰林土壤有机碳储量、细根生物量和凋落物量均显著降低.土壤温度可以分别解释轻度干扰林土壤呼吸(R_S)、异养呼吸(R_H)、自养呼吸(R_A)的84.7%、68.3%、5.1%,可以解释重度干扰林的84.4%、54.6%、21.7%.轻度干扰林和重度干扰林R_S、R_H、R_A的Q_(10)值分别为1.75、1.93、1.27和2.46、2.34、1.65.随着干扰强度的增加,森林生态系统碳储量降低,土壤呼吸下降,且土壤呼吸及其咅组分对外界环境变化的响应更明显,生态系统表现出脆弱性,重度干扰下森林生态系统在短时间内难以恢复.
The effects of mild disturbance and severe disturbance on soil total respiration and heterotrophic respiration of populus tomentosa in subtropical zone were studied.The results showed that soil respiration and its components in severe disturbance forest decreased compared with the mild disturbance , Of which, autotrophic respiration (R_A, 1.75 t C · hm -2 · a -1) decreased by 40% .Compared with the lightly disturbed forest, the soil organic carbon storage, fine root biomass And the amount of litter decreased significantly.The soil temperature could explain 84.7%, 68.3% and 5.1% of soil respiration (R_S), heterotrophic respiration (R_H) and autotrophic respiration (R_A) The Q_ (10) values of R_S, R_H and R_A were 1.75, 1.93, 1.27 and 2.46, 2.34 and 1.65 respectively for lightly disturbed forests and heavily disturbed forests as 84.4%, 54.6% and 21.7% , The carbon storage of forest ecosystem decreased and the soil respiration decreased. The response of soil respiration and its components to the external environment was more obvious, and the ecosystem showed vulnerability. It was difficult to recover the forest ecosystem under severe disturbance in a short time.