土壤呼吸对降雨变化和氮沉降交互作用响应的研究进展

土壤呼吸作为陆地生态系统碳循环的关键过程,对大气CO₂浓度变化有直接影响。研究其如何响应降雨变化、氮沉降增加等全球变化因子,成为近年全球变化领域的热点与难点。与土壤呼吸响应降雨变化或氮沉降增加单个因子相比,研究土壤呼吸对这两个因子交互作用的响应更接近真实的自然环境,可更准确地预估未来土壤碳排放的变化趋势。目前,相关研究涉及全球不同的陆地生态系统,从土壤、微生物和植物层面对其响应机理进行揭示。本文从土壤呼吸及其组分、相关的土壤性质、微生物及植物因素方面,较全面地梳理了不同陆地生态系统土壤呼吸响应降雨变化和氮沉降增加交互作用的研究进展,指出了现有研究中的不足及今后需加强的研究方向,以期为进一步揭示土壤呼吸对降雨变化和氮沉降增加交互作用的响应规律及机制提供参考。

Responses of soil respiration to the interaction of rainfall changes and nitrogen deposition: A review

Soil respiration (R_s), as a key process of carbon cycle in terrestrial ecosystems, has a direct impact on atmospheric CO₂ concentration. How R_s responds to global change factors, such as rainfall changes and increased N deposition, has become a hot and difficult issue in the field of global change. Compared with the responses of R_s to the single factor of rainfall changes or increased N deposition, studying the response of R_s to the interaction of these two factors is more in line with natural environment, which can predict the future changes of soil carbon emission more accurately. At present, the related researches focused on different terrestrial ecosystems all over the world, and revealed the response mechanism from three aspects: soil, microorganism, and plant. Here, the research progress of soil respiration in response to the interaction of rainfall changes and increased N deposition in different terrestrial ecosystems was reviewed from the aspects of R_s and its components, factors related with soil properties, microorganisms and plant, and the deficiencies of current researches, and the research direction to be strengthened in the future were pointed out. Our review would provide a reference for further understanding the response law and the mechanism of soil respiration to the interaction between rainfall changes and increased N deposition.