Profile of Methane Concentrations in Soil and Atmosphere in Alpine Steppe Ecosystem on Tibetan Plateau

作     者：Pei Zhiyong Ouyang Hua Zhou Caiping Xu Xingliang 

作者机构：The Administrative Center for China＇s Agenda 21 Beijing 100038 China Interntional Center for Integrated Mountain Development Kathmanda Nepal Institute of Geographical Sciences and Natural Resources Research CAS Beijing 100101 China 

出 版 物：《Chinese Journal of Population,Resources and Environment》 (中国人口·资源与环境（英文版）)

年 卷 期：2009年第7卷第1期

页      面：3-10页

学科分类：0819[工学-矿业工程] 081903[工学-安全技术及工程] 08[工学] 09[农学] 0903[农学-农业资源与环境] 090301[农学-土壤学] 

基　　金：funded by The National Basic Research Program (Grant No. G1998040800) Pre-studies project of National Basic Research Program (Grant No. 2005CCA05500) 

主　　题：methane concentration profile temperature moisture alpine steppe Tibetan Plateau 

摘      要：The methane concentration profile from -1.5m depth in soil to 32m height in air was measured in alpine steppe lo-cated in the permafrost area. Methane concentrations showed widely variations both in air and in soil during the study period. The mean concentrations in atmosphere were all higher than those in soil, and the highest methane concentration was found in air at the height of 16m with the lowest concentration occur-ring at the depth of 1.5m in soil. The variations of atmospheric methane concentrations did not show any clear pattern both temporally and spatially, although they exhibited a more steady-stable state than those in soil. During the seasonal variations, the methane concentrations at different depths in soil were sig-nificantly correlated (R20.6) with each other comparing to the weak correlations (R20.2) between the atmospheric concentra-tions at different heights. Mean methane concentrations in soil significantly decreased with depth. This was the compositive influence of the decreasing production rates and the increasing methane oxidation rates, which was caused by the descent soil moisture with depth. Although the methane concentrations at all depths varied widely during the growing season, they showed very distinct temporal variations in the non-growing season. It was indicated from the literatures that methane oxidation rates were positively correlated with soil temperature. The higher methane concentrations in soil during the winter were deter-mined by the lower methane oxidation rates with decreasing soil temperatures, whereas methane production rates had no reaction to the lower temperature. Relations between methane contribution and other environmental factors were not discussed in this paper for lacking of data, which impulse us to carry out further and more detailed studies in this unique area.