title: Carbon balance in an alpine steppe in the Qinghai-Tibet plateau.
abstract: Carbon fluxes were measured using a static chamber technique in an alpine steppe in the Qinghai-Tibet Plateau from July 2000 to July 2001. It was shown that carbon emissions decreased in autumn and increased in spring of the next year, with higher values in growth seasons than in winters. An exponential correlation (E(carbon)= 0.22(exp(0.09T) + ln(0.31P+ 1)), R(2)= 0.77, P < 0.001) was shown between carbon emissions and environmental factors such as temperature (T) and precipitation (P). Using the daily temperature (T) and total precipitation (R), annual carbon emission from soil to the atmosphere was estimated to be 79.6 g C/m(2), 46% of which was emitted by microbial respiration. Considering an average net primary production of 92.5 g C/m(2) per year within the 2 year experiment, alpine steppes can take up 55.9 g CO(2)-C/m(2) per year. This indicates that alpine steppes are a distinct carbon sink, although this carbon reservoir was quite small.
authors.affiliation: The Administrative Center for China's Agenda 21, Beijing 100038, China.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Pei
authors.forename: Hua
authors.initials: H
authors.lastname: Ouyang
authors.forename: Cai-Ping
authors.initials: CP
authors.lastname: Zhou
authors.forename: Xing-Liang
authors.initials: XL
authors.lastname: Xu
mesh_terms: D002244:Carbon / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis; D002681:China; D017753:Ecosystem; D004784:Environmental Monitoring; D013696:Temperature
chemical_list: D002245:Carbon Dioxide; D002244:Carbon