湿地甲烷的产生、氧化及排放通量研究进展  

Advance in Studies on Production, Oxidation and Emission Flux of Methane from Wetlands

作　　者：陈槐[1] 周舜[2] 吴宁[1] 王艳芬[3] 罗鹏[1] 石福孙[1] 

机构地区：[1]中国科学院成都生物研究所,成都610041 [2]西华师范大学,四川南充637002 [3]中国科学院研究生院生物系,北京100039

出　　处：《应用与环境生物学报》2006年第5期726-733,共8页Chinese Journal of Applied and Environmental Biology

基　　金：中国科学院重要方向项目(KSCX2-01-09);国家"十五"攻关项目(2001BA606A-05);四川省青年科技基金项目(03ZQ026-043)~~

摘　　要：甲烷研究已倍受科学界关注，不仅由于其对全球变暖的贡献仅次于二氧化碳，贡献率达25％，还因为单分子甲烷的增值潜势是二氧化碳的15-30倍．湿地是甲烷的重要来源，估计湿地生态系统对全球甲烷排放的贡献率约为20％，即为100-200Tg a^-1．湿地甲烷在厌氧条件下产生，在土壤氧化层以及根际中部分氧化，然后通过土壤、水体和植物体排放到大气中去．就近10a来湿地甲烷产生、氧化、传输过程及其影响因素等的研究进展进行了综述．产甲烷菌的研究主要集中在其对环境因子的生理生态和分子生物学，尤其集中在稻田产甲烷菌的研究上，因此在深度和广度上都有待突破．产甲烷过程是一个复杂的生化过程，要对甲烷排放量估计、甲烷排放动态研究以及在甲烷排放建模等方面取得进展，必需在甲烷产生机制上进行突破．甲烷氧化菌的研究集中于菌群对环境的适应以及其自身氧化能力上，应用研究还不是很深入．甲烷氧化过程的研究已经有了一定的深度，但氧化过程具体机理的研究还有待进一步深入，这需要分子生物学以及基因组学等多学科的交叉．甲烷传输过程是研究甲烷排放动态的基础，目前相关研究较少，国内有关研究主要集中在稻田研究上，对高寒湿地的研究则几乎是空白．湿地甲烷通量的研究是目前温室气体研究的热点问题，但主要解决的问题是大气中甲烷气体浓度增加与湿地甲烷通量的关系．湿地甲烷通量是由多种因素决定的，对影响湿地甲烷通量的因素的研究相当丰富，特别是近年来对生物因素的关注．由于学科的发展，近10a在这方面的研究较之过去更为全面和系统．Methane is an important greenhouse gas, ranking second to carbon dioxide. Moreover, the methane concentration in the atmosphere has greatly increased in recent years. Wetlands （swamps, bogs, fens, rice fields, etc. ） are important sources of methane. It is assumed that 20% of the global methane budgets emitted from wetlands, i. e. , about 100 -200 Tg a^-1. So researches are more focused on methane flux of wetlands. Methane flux of wetlands is determined by methane production under anaerobic condition, methane oxidation in rhizophere and oxidizing layers in soils, and methane transport from soils to the atmosphere. Firstly, methane generation or production is the basis of methane flux. Research in this field is, therefore, developed. As for the production progress, there are two different ways： anaerobic fermentation and CO2 reduction. But the detailed chemical reactions of this process are never well understood. Secondly, methane oxidation is also of great importance in research of methane flux. The research about the bacteria related to methane oxidation is concentrated in environmental factors and their biochemical properties. However, the oxidizing process is well known and there are two ways for the oxidation： high affinity oxidation and low affinity oxidation. Thirdly, the methane transport is the last and important step in methane flux of wetlands. There are three major ways of this transport： diffusion, ebullition and transport from vegetation. The transport from vegetation has recently attracted scientists＇ interest. The pathway and quantity of methane emitted through plants vary according to the characteristics of plant species involved. Lastly, the impact factors of methane flux are summarized, including biotic and abiotie factors. In this paper, the soil, water, vegetation and climate factors for methane flux are analyzed and discussed.

关 键 词：湿地 甲烷排放通量 甲烷产生 甲烷氧化 甲烷传输 

分 类 号：X51[环境科学与工程—环境工程]