若尔盖高原季节性淹水沼泽两个生长季甲烷排放通量  

Methane emission fluxes from seasonal flooding marshy wetland on the Zoigê Plateau during two growing seasons

作　　者：崔丽娟[1] 周文昌[1,2] 王义飞[1] 李伟[1] 康晓明[1] 

机构地区：[1]中国林业科学研究院湿地研究所,湿地生态过程与功能北京市重点实验室,北京100091 [2]湖北省林业科学研究院,武汉430075

出　　处：《应用与环境生物学报》2017年第6期1067-1073,共7页Chinese Journal of Applied and Environmental Biology

基　　金：中国林业科学研究院林业新技术研究所基本科研业务费专项(CAFINT2014K06);中国清洁发展机制基金赠款项目(2012076)资助~~

摘　　要：为了解若尔盖高原湿地甲烷(CH_4)排放年际变化并准确估算高原湿地CH_4排放通量,在若尔盖高原湿地国家级自然保护区建立1 hm^2季节性淹水沼泽湿地标准样地;于2013和2014年通过静态箱和快速温室气体分析仪测量两个生长季沼泽湿地微地貌区草丘(Hummock)和洼地(Hollow)CH_4排放通量.结果表明:2013年生长季(6^(-1)0月),若尔盖高原湿地微地貌区草丘和洼地CH_4排放通量平均值为7.59和10.12 mg m^(-2) h^(-1),2014年生长季(5^(-1)0月)则分别为0.62和2.74mg m^(-2) h^(-1).2013年生长季湿地微地貌区草丘和洼地CH_4排放通量平均值分别是2014年的12倍和4倍,2014年生长季湿地CH_4排放通量下降的原因可能是夏季(6-8月)水位下降,降低了产CH_4菌群落数量而减少CH_4产生,同时增加了CH_4氧化菌氧化层厚度而加强CH_4氧化,降低CH_4排放通量.另外,发现湿地水位下降,降低了湿地CH_4排放通量对土壤温度的敏感性,表现为Q_(10)值变小.综上,夏季期间的水位在调控若尔盖高原季节性淹水湿地CH_4排放过程中起着关键作用.To enhance our understanding of the interannual variation of methane （CH4） emission on the Zoigê Plateau wetland in China and to accurately estimate CH4 emission fluxes from the plateau wetlands, we established a standard sampling area （1 hm2） of seasonal flooding marshy wetland in Zoigê wetland national nature reserve. CH4 emission fluxes from the hummock and hollow were measured using the dark static chamber technique and Fast Greenhouse Gas Analyzer during two growing seasons in 2013 and 2014. In the 2013 growing season （June to October）, the average CH4 emission fluxes from the wetland on the hummock and hollow were 7.59 mg m-2 h-1 and 10.12 mg m-2 h-1. In the 2014 growing season （May to October）, the average CH4 emission fluxes from wetland on the hummock and hollow were 0.62 mg m-2 h-1 and 2.74 mg m-2 h-1. The CH4 emission fluxes of the hummock and hollow were 12 and 4 times higher in 2013 than in 2014. The decline in CH4 emission fluxes was probably caused by a fall in the water table level during the summer （June to August）; the resulting shift to aerobic conditions could reduce the population of methanogens and stimulate CH4 oxidation. Moreover, a marked fall in the water table level might decrease the sensitivity of the CH4 emission flux to soil temperature, and this was evidenced by the decrease in the Q10 values in 2014. In conclusion, in the summer, water table level is a key factor controlling methane emission flux from the seasonal flooding wetland in the Zoigê Plateau.

关 键 词：甲烷排放通量 草丘 洼地 水位 若尔盖高原湿地 

分 类 号：X171[环境科学与工程—环境科学]