生物与非生物因素对森林土壤氮矿化的调控机制

温室气体排放剧增引起全球变暖，已成为全球高度关注的生态环境问题。一氧化二氮(N₂O)是大气中仅次于二氧化碳(CO₂)和甲烷(CH₄)的第三大温室气体，森林土壤氮矿化过程伴随着硝化和反硝化的发生，能够导致N₂O的产生，进而引起大气N₂O浓度的升高。森林土壤氮矿化是生物与非生物环境因素共同调控的复杂生态学过程，探明森林土壤氮矿化的影响因素及其调控机制，有助于丰富人们对森林土壤氮循环过程的认识，在全球变化研究中具有重要的地位与作用。本研究揭示森林土壤氮矿化的时空变化及影响因素，阐明非生物因素以及森林植被覆盖、森林凋落物、土壤微生物与土壤动物等生物因素对森林土壤氮矿化的影响特征及作用机制。目前，森林土壤氮矿化研究存在结果可比性不强；内容多集中于氮矿化单因素影响研究，缺乏多因子尤其是微生物-动物协同调控研究；缺乏不同气候类型及不同土地利用方式森林土壤氮矿化特征及影响机制研究；缺乏氮矿化对全球变化的响应研究等一系列问题。土壤氮矿化研究应该探索统一高效的测定方法，加强土壤微生物-动物-环境因子多因素耦合对森林土壤氮矿化影响机制研究，探讨不同气候类型及不同利用方式森林土壤氮矿化调控机制，重点阐明全球变化背景下森林土壤氮矿化的过程与机理。旨在为准确理解不同气候区森林土壤氮矿化的时空格局及其对全球气候变化的影响提供理论支撑。参69

Regulation mechanism of biotic and abiotic factors on the nitrogen mineralization of forest soil

Global warming, a global ecological and environmental problem, attributes to the rapidly increased emission of greenhouse gases of which N₂O ranks the third in the atmosphere after CO₂ and CH₄. On the one hand, nitrification and denitrification often take place in the process of forest soil nitrogen mineralization where N₂O is produced from soils, thus, increasing the atmospheric N₂O concentration. On the other hand, forest soil nitrogen mineralization, as a complex ecological process, is regulated by the interactions of biotic and abiotic environmental factors. Therefore, the investigation of the influencing factors and the regulatory mechanism of forest soil nitrogen mineralization, is conducive to the promotion of people’s understanding of the nitrogen cycling process of forest soils, thus playing an important role in the study of global change. However, previous studies on the nitrogen mineralization of forest soils were mainly limited to the effect of single factors with the lack of comparable research results, the cooperative regulation research on multiple factors (e.g., microbial-animal interaction), the study of forest soil nitrogen mineralization characteristics and impact mechanism under different circumstances of climate and land-use, and the research on the response of nitrogen mineralization to global climate change. Aimed to provide theoretical support for better understanding the spatiotemporal patterns of forest soil nitrogen mineralization in different climatic areas and their effects on global climate change, this study has conducted an examination of the spatiotemporal variations and the influencing factors of forest soil nitrogen mineralization, and provided an explanation of the characteristics and mechanism of the effect of abiotic (e.g., soil physicochemical environments) and biotic factors (e.g., forest vegetation cover, forest litter, and soil microorganisms and fauna) on forest soil nitrogen mineralization. It is advised that researches on soil nitrogen mineralization should, with unified and efficient methods, be focused on the influencing mechanism of the multi-factor coupling of soil microorganisms-fauna-environmental factors on forest soil nitrogen mineralization, the regulation mechanism of soil nitrogen mineralization under different climate and land-use circumstances, as well as the processes and mechanisms of forest soil nitrogen mineralization under the background of global change. [Ch, 69 ref.]