Relations between Carbon Dioxide Fluxes and Environmental Factors of Kobresia humilis Meadows and Potentilla fruticosa Meadows

作     者：ZHAO Liang XU Shixiao LI Yingnian TANG Yanhong ZHAO Xinquan GU Song DU Mingyuan YU Guirui 

作者机构：Northwest Plateau Institute of BiologyChinese Academy of ScienceXining 810001China National Institute for Environmental StudiesTsukubaIbaraki 3050053Japan National Institute for Agro-Environmental ScienceTsukubaIbaraki 3058604Japan Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China Key Laboratory of Adaption and Evolution of Peatean BiotaNorthwest Institute of Plateau BiologyChinese Academy of SciencesXin’ging 810001China 

出 版 物：《Frontiers in Biology》 (生物学前沿（英文版）)

年 卷 期：2007年第2卷第3期

页      面：324-332页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070303[理学-有机化学] 0703[理学-化学] 

主　　题：alpine meadow vegetation type net carbon dioxide exchange eddy covariance technology 

摘      要：Carbon dioxide fluxes of Kobresia humilis and Potentilla fruticosa shrub meadows,two typical ecosystems in the Qinghai-Tibet Plateau,were measured by eddy covari-ance technology and the data collected in August 2003 were employed to analyze the relations between carbon dioxide fluxes and environmental factors of the *** is the time when the two ecosystems reach their peak leaf area indexes and stay stable,and also the period when the net carbon absorptions of Kobresia humilis and Potentilla fruticosa shrub meadows reach 56.2 g C·m^(-2)and 32.6 g C·m^(-2),with their highest daily carbon dioxide absorp-tions standing at 12.7μmol·m^(-2)·s^(-1)and 9.3μmol·m^(-2)·s^(-1),and their highest carbon discharges at 5.1μmol·m^(-2)·s^(-1)and 5.7μmol·m^(-2)·s^(-1),*** the same photosynthetic photo flux densities(PPFD),the carbon dioxide-uptake rate of the Kobresia humilis meadow is higher than that of the Potentilla fruticosa shrub meadow;where the PPFD are higher than 1,200μmol·m^(-2)·s^(-1).The carbon dioxide uptake rates of the two ecosystems declined as air temperature increased,but the carbon dioxide uptake rate of the Kobresia humilis meadow decreased more quickly(-0.086)than that of the Potentilla fruticosa shrub meadow(-0.016).Soil moistures exert influence on the soil respirations and this varies with the vegetation *** daily carbon dioxide absorptions of the ecosystems increase with increased diurnal temperature differences and higher diurnal temperature differences result in higher carbon dioxide *** exists a negative correlation between the vegetation albedos and the carbon dioxide fluxes.