CAJ | 학술논문

土壤呼吸是当前区域碳收支及全球变化研究中的一个热点问题.降雨作为一个重要的扰动因子,对准确估算土壤呼吸具有重要影响,这在干旱和半干旱地区尤为明显.尽管关于土壤呼吸对降雨响应过程与规律的研究已取得了较大进展,但是对于其机制的解释仍然存在较大的争议,集中体现在对"Birch效应"(降雨强烈激发土壤呼吸的现象)的解释上,即到底是"底物供应改变机制"还是"微生物胁迫机制"在调控该过程.该文综述了土壤呼吸对降雨事件、降雨量及降雨格局的响应过程与规律;阐述了土壤呼吸各组分对降雨响应的差异,分析了雨后物理替代与阻滞、底物供应、根系和微生物活性、微生物群落结构与功能等一系列过程引起土壤呼吸改变的机制;重点阐述了微生物对土壤水分波动的响应与适应机制.在此基础上提出了今后需重点关注的4个方面:1)"底物供应改变机制"与"微生物胁迫机制"的区分;2)土壤呼吸各组分对降雨响应的差异;3)不同时空尺度上土壤呼吸对降雨响应的模拟与估算;4)降雨带来的外援N和H~+的作用.
토양호흡시당전구역탄수지급전구변화연구중적일개열점문제.강우작위일개중요적우동인자,대준학고산토양호흡구유중요영향,저재간한화반간한지구우위명현.진관관우토양호흡대강우향응과정여규률적연구이취득료교대진전,단시대우기궤제적해석잉연존재교대적쟁의,집중체현재대"Birch효응"(강우강렬격발토양호흡적현상)적해석상,즉도저시"저물공응개변궤제"환시"미생물협박궤제"재조공해과정.해문종술료토양호흡대강우사건、강우량급강우격국적향응과정여규률;천술료토양호흡각조분대강우향응적차이,분석료우후물리체대여조체、저물공응、근계화미생물활성、미생물군락결구여공능등일계렬과정인기토양호흡개변적궤제;중점천술료미생물대토양수분파동적향응여괄응궤제.재차기출상제출료금후수중점관주적4개방면:1)"저물공응개변궤제"여"미생물협박궤제"적구분;2)토양호흡각조분대강우향응적차이;3)불동시공척도상토양호흡대강우향응적모의여고산;4)강우대래적외원N화H~+적작용.
Soil respiration is an important issue in research on regional carbon budget and global change. Rainfall, which acts as an important disturbance to soil respiration, leads to large uncertainties in estimating carbon exchange be-tween soil and the atmosphere, especially in arid and semiarid regions. Although significant progress on the re-sponse of soil respiration to rainfall has been made, considerable controversies on its mechanism still exist. There are two different mechanisms to interpret the "Birch effect", which is characterized by a strong soil CO_2 emission soon after a rainfall event: "the substrate supply change mechanism" and "microbial stress mechanism". We review progress in the study of the response of soil respiration to rainfall and summarize the responses of different components of soil respiration to the changes induced by rainfall, including physical replacement and blockage, substrate supply change, activity change of root system and microbes and changes in the structure and function of the microbial community. We also point out four important aspects to be considered in the future: 1) evaluating the function of "substrate supply change mechanism" and "microbial stress mechanism" to the "Birch effect", 2) quantifying the response of soil respiration to rainfall based on different components, 3) modeling and estimating the response of soil respiration to rainfall on different temporal and spatial scales, and 4) evaluating the possible effects of N and H~+ from rainfall on soil respiration.