title: Biophysical regulation of carbon fluxes over an alpine meadow ecosystem in the eastern Tibetan Plateau.
abstract: The eddy covariance method was used to measure net ecosystem CO2 exchange (NEE) between atmosphere and an alpine meadow ecosystem in the eastern Tibetan Plateau of China in 2010. Our results show that photosynthesis was reduced under low air temperature (T a), high vapor pressure deficit (VPD), and medium soil water content (SWC) conditions, when compared to that under other T a (i.e., medium and high), VPD (i.e., low and medium), and SWC (i.e., low and high) conditions. The apparent temperature sensitivity of ecosystem respiration (Q 10) declined with progressing phenology during the growing season and decreased with an increase of soil temperature (T s) during the non-growing season. Increased ecosystem respiration (R eco) was measured during spring soil thawing. By the path analysis, T a, T s, and VPD were the main control factors of CO2 exchange at 30-min scale in this alpine meadow. Integrated NEE, gross primary production (GPP), and R eco over the measured year were -156.4, 1164.3, and 1007.9 g C m(-2), respectively. Zoige alpine meadow was a medium carbon sink based on published data for grassland ecosystems.
authors.affiliation: Key Laboratory of Land Surface and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Institute, Chinese Academy of Sciences, Lanzhou, 730000, China.
authors.forename: Shaoying
authors.initials: S
authors.lastname: Wang
authors.affiliation: Key Laboratory of Land Surface and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Institute, Chinese Academy of Sciences, Lanzhou, 730000, China. yuzhang@lzb.ac.cn.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Land Surface and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Institute, Chinese Academy of Sciences, Lanzhou, 730000, China.
authors.forename: Shihua
authors.initials: S
authors.lastname: Lü
authors.affiliation: Key Laboratory of Land Surface and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Institute, Chinese Academy of Sciences, Lanzhou, 730000, China.
authors.forename: Peixi
authors.initials: P
authors.lastname: Su
authors.affiliation: Key Laboratory of Land Surface and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Institute, Chinese Academy of Sciences, Lanzhou, 730000, China.
authors.forename: Lunyu
authors.initials: L
authors.lastname: Shang
authors.affiliation: Key Laboratory of Land Surface and Climate Change in Cold and Arid Regions, Cold and Arid Regions Environmental and Engineering Institute, Chinese Academy of Sciences, Lanzhou, 730000, China.
authors.forename: Zhaoguo
authors.initials: Z
authors.lastname: Li
mesh_terms: D057486:Carbon Cycle; D002245:Carbon Dioxide; D065948:Grassland; D008962:Models, Theoretical; D011891:Rain; D012987:Soil; D013472:Sunlight; D013696:Temperature; D018609:Tibet; D055548:Vapor Pressure
chemical_list: D012987:Soil; D002245:Carbon Dioxide
keywords: Alpine meadow; Ecosystem respiration; Net ecosystem CO2 exchange; Tibetan Plateau