Seasonal Patterns of Soil Respiration in Three Types of Communities along Grass-Desert Shrub Transition in Inner Mongolia, China  

作　　者：金钊 齐玉春 董云社 Manfred DOMROES 

机构地区：[1]Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences,Beijing 100101 [2]State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment,Chinese Academy of Sciences,Xi'an 710075 [3]Institute of Geography, Mainz University,Mainz 55099,Germany

出　　处：《Advances in Atmospheric Sciences》2009年第3期503-512,共10页大气科学进展（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos. 40730105, 40501072, and 40673067);the Ministry of Science and Technology of China (Grant Nos.2007BAC03A11 and 2002CB412503);The Knowledge Innovation Program of the Institute of Geographical Sciences;Natural Resources Research of the Chinese Academy of Sciences (The effect of human activities on re-gional environmental quality, health risk, and environmen-tal remediation)

摘　　要：The seasonal dynamics of soil respiration in steppe （S. bungeana）, desert shrub （A. ordosica）, and shrubperennial （A. ordosica ＋C. komarovii） communities were investigated during the growth season （May to October） in 2006; their environmental driving factors were also analyzed. In the three communities, soil respiration showed similar characteristics in their growth seasons, with peak respiration values in July and August owing to suitable temperature and soil moisture conditions during this period. Meanwhile, changes in soil respiration were greatly influenced by temperatures and surface soil moistures. Soil water content at a depth of 0 to 10 cm was identified as the key environmental factor affecting the variation in soil respiration in the steppe. In contrast, in desert shrub and shrub-perennial communities, the dynamics of soil respiration was significantly influenced by air temperature. Similarly, the various responses of soil respiration to environmental factors may be attributed to the different soil textures and distribution patterns of plant roots. In desert ecosystems, precipitation results in soil respiration pulses. Soil carbon dioxide （CO2） effluxes greatly increased after rainfall rewetting in all of the ecosystems under study. However, the precipitation pulse effect differed across the ecosystem. We propose that this may be a result of a reverse effect from the soil texture.The seasonal dynamics of soil respiration in steppe （S. bungeana）, desert shrub （A. ordosica）, and shrubperennial （A. ordosica ＋C. komarovii） communities were investigated during the growth season （May to October） in 2006; their environmental driving factors were also analyzed. In the three communities, soil respiration showed similar characteristics in their growth seasons, with peak respiration values in July and August owing to suitable temperature and soil moisture conditions during this period. Meanwhile, changes in soil respiration were greatly influenced by temperatures and surface soil moistures. Soil water content at a depth of 0 to 10 cm was identified as the key environmental factor affecting the variation in soil respiration in the steppe. In contrast, in desert shrub and shrub-perennial communities, the dynamics of soil respiration was significantly influenced by air temperature. Similarly, the various responses of soil respiration to environmental factors may be attributed to the different soil textures and distribution patterns of plant roots. In desert ecosystems, precipitation results in soil respiration pulses. Soil carbon dioxide （CO2） effluxes greatly increased after rainfall rewetting in all of the ecosystems under study. However, the precipitation pulse effect differed across the ecosystem. We propose that this may be a result of a reverse effect from the soil texture.

关 键 词：soil respiration grass-desert shrub transition Stipa bungeana Artemisia ordosica Artemisiaordosica ＋ Cynanchum komarovii Ordos Plateau 

分 类 号：P461.4[天文地球—大气科学及气象学]