长江安庆段河流湿地生态系统呼吸及其影响因子韩帅黄玲玲王昭艳.DOCVIP

长江河流湿地生态系统呼吸及其影响因子(韩 帅 黄玲玲 王昭艳 魏 远 张旭东* （中国林业科学研究院林业研究所，北京 100091） 摘要：研究湿地生态系统呼吸（Reco）对评价湿地生态系统碳汇功能具有重要的意义。采用涡度相关法对位于长江中游河流湿地的杨树人工林生态系统进行了长期的定位观测，根据2005.7.23－2007.12.15的数据对Reco进行估算，并分析Reco对主要环境因子的响应特征。结果表明：（1）Reco具有明显的季节变化，每年的最大值出现在8月，最小值出现在1月，Reco受空气温度、土壤温度和土壤含水量共同影响，总体上看空气温度是驱动Reco的主要因子；（2）在几种模拟生态系统呼吸的模型中，Van’t Hoff方程、Arrhenius方程、Lloyd-Talor方程在统计意义上具有同等的能力，由空气温度和土壤含水量共同驱动的连乘模型对Reco的拟合效果最好；（3）使用连乘模型估算的2006年生态系统呼吸总量为1074.7 gC·m-2·a-1，2007年为1127.0 gC·m-2·a-1，与亚热带和温带的森林站点的测定值相接近。 关键词： 长江；河流湿地；生态系统呼吸；涡度相关 Ecosystem respiration and its controlling factors in the riparian wetland of Yangtze River HAN Shuai, HUANG Ling-ling, WANG Zhao-yan, WEI Yuan, ZHANG Xu-dong* (Research Institute of Forestry of CAF, Beijing 100091) Abstract: Research of ecosystem respiration (Reco) in wetland ecosystem is critical for estimating wetland ecosystem carbon balance. Continuous eddy covariance measurements were made in a poplar plantation located in the riparian wetland of middle reaches of Yangtze River. Reco was estimated and analyzed for its regulatory factors based on data from 2005.7.23 through 2007.12.15. We found that: (1) Reco had an obvious seasonal fluctuation with peak Reco in August and minimum in January. The seasonal change was affected by canopy air temperature, soil temperature, and soil water content, with canopy air temperature as the most important factor; (2) exponential equations (e.g., Van’t Hoff, Arrhenius and Lyold-Talor) were effective in modeling Reco with canopy air temperature and soil water content; (3) Reco in 2006 and 2007 were 1074.7 and 1127.0 gC·m-2·a-1, respectively, based on the multiplicative model. These estimates were closed to forest sites in subtropical and temperate zones. Key Words: Yangtze River; riparian wetland; ecosystem respiration; eddy covariance 湿地是陆地生态系统中最重要的碳库之一，全球湿地面积仅占陆地面积的1 %，碳储量却占陆地生态系统碳储存总量的15%[1]。湿地生态系统是水域生态系统向陆地生态系统过渡的特殊的生态系统，经常受到干扰，生态系统脆弱，气候的微小变化会导致湿地生态系统碳循环过程的改变，打破原有碳平衡，甚至使湿地碳的源汇关系发生逆转[2]。目前，关于湿地源/汇的问题还没有一致性结论，Bridges[3]