地下水位和土壤含水量对若尔盖木里苔草沼泽甲烷排放通量的影响  

Effect of Water Table and Soil Water Content on Methane Emission Flux at Carex muliensis Marshes in Zoige Plateau

作　　者：李丽[1] 雷光春[1] 高俊琴[1] 吕偲[1] 周延[1] 贾亦飞[1] 杨萌[1] 索郎夺尔基 

机构地区：[1]北京林业大学自然保护区学院,北京100083 [2]若尔盖湿地国家级自然保护区管理局,四川若尔盖624500

出　　处：《湿地科学》2011年第2期173-178,共6页Wetland Science

基　　金：林业公益项目(200804005);国家重点基础研究发展计划项目(2009CB421103)资助

摘　　要：在若尔盖湿地国家级自然保护区典型的木里苔草(Carex muliensis)沼泽地中,选择地下水位不同的4个采样点,其植物生长季的平均地下水位分别为距离地表53.94 cm、31.35 cm、11.50 cm和4.74 cm。利用密闭式静态箱定期采集气体样品,并在实验室用Shimadzu GC212A气相色谱仪测定CH_4气体浓度,分析了CH_4排放通量与地下水位和土壤含水量之间的关系。研究结果表明,地下水位和土壤含水量对CH_4排放通量产生明显影响,6～9月观测日中,CH_4排放通量随着地下水位的升高而呈指数增加;10～40 cm土层的土壤含水量与CH_4排放通量呈现显著正相关(n=36,p<0.05),而0～10 cm土壤含水量与生长季CH_4排放通量不相关(n=12,p>0.05),逐步线性回归分析表明,20～30 cm土层的土壤含水量是影响CH_4排放通量的主要因素(n=12,p<0.01)。This study was conducted at a typical Carex muliensis marshes in Zoige Wetland National Nature Reserve located in the eastern edge of Qinghai-Tibet Plateau of China.Four sites that characterized by different groundwater tables were selected as the sampling sites,in which mean groundwater tables from low to high during the plant growing season were 53.94 cm,31.35 cm,11.50 cm,and 4.74 cm below the surface respectively, where a set of static closed chambers had been installed to take methane gas samples each month from June to September 2009.All samples were packed and sent to laboratory for measuring methane concentration within one week,and they were measured at the same conditions with Shimadzu GC212A gas chromatography. The results showed methane emission flux correlated with the groundwater table exponentially（n= 16,p0.01）,and methane emission flux increased with the groundwater table rising during the observation period from June to September 2009.The soil water content also played significant role in controlling methane emission.Soil water content was significantly correlated with methane emission flux（n=36,p0.05） at soil depth of 10-40 cm,but no significant relationship between soil water content and methane emission flux were observed at the soil depth of 0-10 cm（n=12,p0.05）.Further analysis indicated that soil water content at the depth of 20-30 cm was main factor regulating CH_4 emission flux（n=12,p0.01）.

关 键 词：若尔盖高原 沼泽 CH4排放通量 地下水位 土壤含水量 

分 类 号：X16[环境科学与工程—环境科学] S944[农业科学—水产养殖]