增温对土壤N2O和CH4排放的影响与微生物机制研究进展

全球变暖已引起人们的广泛关注,大气温室效应气体浓度增加是导致全球变暖的主要因素之一,土壤是温室效应气体的主要来源。反过来,全球变暖对土壤温室气体的排放具有反馈作用。温度升高不仅会影响植物、动物、微生物的生长及其相互作用,还会影响土壤的物质(尤其是氮、碳)循环过程,从而影响土壤温室效应气体的排放。本文主要总结了增温对土壤主要温室气体N₂O和CH₄排放的影响及其微生物机制。总体来看,增温能够促进这两种温室气体的排放,其排放主要与温度对氨氧化细菌(AOB)、反硝化功能基因、甲烷产生菌和甲烷氧化菌的丰度和组成的影响有关。土壤温室气体排放也受到植物的物种特性、养分吸收和群落组成,以及土壤营养元素含量、含水量、pH值等理化性质的影响。未来应更深入地从微生物角度探讨全球变暖对土壤温室气体排放的反馈作用机制,加强不同增温模式对土壤温室气体排放的影响研究,并关注增温与其他环境因子相互作用对土壤温室气体排放的影响等,以期为全球变暖对土壤温室气体排放反馈作用的预测提供理论依据。

Progress in the effects of warming on soil N2O and CH4 emission and the underlying micro-bial mechanisms

Global warming has received widespread concern. The increasing concentration of greenhouse gases (GHG) is one of the major factors contributing to global warming. Soil is a major source of GHG. Global warming could feed back on soil GHG emission. Warming influences the growth of plants, animals, microbes and their interactions, as well as the cycling of soil matters (especially nitrogen and carbon). Consequently, warming has the potential to affect soil GHG emission. We summarized the effects of warming on soil N₂O, and CH₄ emissions and the underlying mechanisms. In general, warming increased the emission of these two greenhouse gases, which are mainly related to the effects of temperature on the abundance and composition of ammonia oxidizing bacteria, denitrification functional genes, methane-producing bacteria and methane-oxidizing bacteria. Soil GHG emissions are affected by plant species characteristics, nutrient uptake and community composition, as well as soil nutrient element content, water content, pH and other physical and chemical properties. Further studies are needed to elucidate the microbial mechanisms of GHG emission. In addition, various warming patterns should be considered in the study of GHG emissions, and more attention should be paid on the interactive effects between warming and other environmental factors. It will provide solid theoretical basis for the prediction of global climate change and GHG emissions.