植物生态学报 ›› 2010, Vol. 34 ›› Issue (5): 601-610.DOI: 10.3773/j.issn.1005-264x.2010.05.014

所属专题: 碳水能量通量

• 综述 • 上一篇    下一篇

土壤呼吸对降雨响应的研究进展

王义东1,2, 王辉民1,*(), 马泽清1, 李庆康1, 施蕾蕾1,2, 徐飞1,2   

  1. 1中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室千烟洲生态站, 北京 100101
    2中国科学院研究生院, 北京 100049
  • 收稿日期:2009-07-04 接受日期:2009-11-24 出版日期:2010-07-04 发布日期:2010-05-01
  • 通讯作者: 王辉民
  • 作者简介:* E-mail: wanghm@igsnrr.ac.cn

Review of response mechanism of soil respiration to rainfall

WANG Yi-Dong1,2, WANG Hui-Min1,*(), MA Ze-Qing1, LI Qing-Kang1, SHI Lei-Lei1,2, XU Fei1,2   

  1. 1Qianyanzhou Ecological Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
    2Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2009-07-04 Accepted:2009-11-24 Online:2010-07-04 Published:2010-05-01
  • Contact: WANG Hui-Min

摘要:

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。

关键词: 干湿交替, Birch效应, 碳循环, 降雨格局, 土壤碳通量

Abstract:

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 between soil and the atmosphere, especially in arid and semiarid regions. Although significant progress on the response 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 CO2 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.

Key words: alternation of dry and wet, Birch effect, carbon cycle, precipitation pattern, soil CO2 efflux