互花米草入侵对沿海湿地甲烷排放的影响  

Effects of Spartina alterniflora invasion on methane emission from coastal brackish marsh

作　　者：项剑[1,2] 刘德燕[1] 袁俊吉[1,2] 丁维新[1] 

机构地区：[1]土壤与农业可持续发展国家重点实验室,中国科学院南京土壤研究所,南京210008 [2]中国科学院研究生院,北京100049

出　　处：《生态学杂志》2012年第6期1361-1366,共6页Chinese Journal of Ecology

基　　金：中国科学院知识创新工程重要方向性项目(KZCX2-YW-439);战略科技先导专项(XDA05020500);国家自然科学基金项目(41001045;41171190);江苏省创新学者攀登项目(BK2008057)

摘　　要：采集互花米草不同入侵年限(8、11和15年)的原状土壤,采用盆栽试验,研究了土壤有机碳含量对沿海湿地CH4排放的影响。结果表明,土壤有机碳含量随着互花米草入侵年限的增加而增加。在植物生长季,互花米草入侵15年的土壤有机碳含量为12.97g·kg-1,土壤CH4排放通量为2.94mg·m-2·h-1,显著高于入侵年限为8和11a(有机碳含量为8.11和9·16g·kg-1)的土壤,其土壤CH4排放通量分别为1.95和2.34mg·m-2·h-1。这主要是由于随着土壤有机碳含量提高,不仅为产甲烷菌提供了更多底物,同时也促进了产甲烷菌数量增加,从而导致更多CH4排放。因此,在评价互花米草入侵的综合环境效应时,需要兼顾土壤固碳能力和温室气体排放。Natural wetland is one of the key sources for atmospheric methane. Spartina alterniflo- ra invasion generally increases the soil organic carbon content in coastal marshes of China. In this study, three intact soil cores were collected from the coastal brackish marshes having been inva- ded by S. alterniflora for 8, 11 and 15 years, respectively, and a pot experiment was conducted to investigate the effects of soil organic carbon content on the methane emission from coastal brackish marsh. The soil organic carbon content increased with the increasing year of S. alterni- flora invasion, and the methane emission had an apparent seasonal pattern, with the peak in Sep- tember. During growth season, the mean methane flux of the marsh having been invaded by S. alterniflora for 15 years and with the soil organic carbon content of 12.97 g ~ kg-1 amounted to 2.94 mg ~ m-2 ~ h-~, which was significantly higher than that （ 1.95 and 2.34 mg ~ m-2 ~ h-~ ） of the marshes after 8 and 11 years S. alterniflora invasion and with the soil organic carbon con- tent of 8.11 and 9.16 g ~ kg-1, respectively. It was considered that the increased soil organic carbon content not only increased the supply of dissolved organic carbon for methanogens, but also stimulated the growth of methanogens, which together elevated the methane emission from the coastal marshes invaded by S. alterniflora.

关 键 词：甲烷 互花米草 土壤有机碳 沿海湿地 入侵 

分 类 号：X502[环境科学与工程—环境工程] X173