Fluxes of CH4 and N_2O from soil under a tropical seasonal rain forest in Xishuangbanna, Southwest China

作     者：YAN Yuping SHA Liqing CAO Min ZHENG Zheng TANG Jianwei WANG Yinghong ZHANG Yiping WANG Rui LIU Guangren WANG Yuesi SUN Yang 

作者机构：Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduated School of the Chinese Academy of Sciences Beijing 100049 China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2008年第20卷第2期

页      面：207-215页

核心收录：

学科分类：07[理学] 070602[理学-大气物理学与大气环境] 0706[理学-大气科学] 

基　　金：the Knowledge Innovation Project of Chinese Academy of Sciences (No. KZCX1-SW-01) 国家自然科学基金 国家973计划 

主　　题：global warming greenhouse gases rain forest seasonal variability soil moisture soil temperature 

摘      要：CH4 and N2O fluxes from soil under a tropical seasonal rain forest in Xishuangbanna, Southwest China were measured for one year using closed static chamber technique and gas chromatography method. Three treatments were set in the studied field： （A） litter-free, （B） with litter, and （C） with litter and seedling. The results showed that the soil in our study was a sink of atmospheric CH4 and source of atmospheric N2O. The observed mean CH4 fluxes from treatments A, B, and C were -50.0 ± 4.0, -35.9 ± 2.8, -31.6 ± 2.8 μgC/（m^2·h）, respectively, and calculated annual fluxes in 2003 were -4.1, -3.1, and -2.9 kgC/hm^2, respectively. The observed mean N2O fluxes from treatments A, B, and C were 30.9 ± 3.1, 28.2 ± 3.5, 50.2±3.7 μgN/（m^2·h）, respectively, and calculated annual fluxes in 2003 were 2.8, 2.6, and 3.7 kgN/hm^2, respectively. Seasonal variations in CH4 and N2O fluxes were significant among all the three treatments. The presence of litter decreased CH4 uptake during wet season （P 〈 0.05）, but not during dry season. There was a similar increase in seedlings-mediated N2O emissions during wet and dry seasons, indicating that seedlings increased N2O emission in both seasons. A strong positive relationship existed between CH4 fluxes and soil moisture for all the three treatments, and weak relationship between CH4 fluxes and soil temperature for treatment B and treatment C. The N2O fluxes correlated with soil temperature for all the three treatments.