Journal of Plant Research

, Volume 123, Issue 4, pp 531–541

Small-scale variation in ecosystem CO2 fluxes in an alpine meadow depends on plant biomass and species richness

Authors

    • Graduate School of Life and Environmental SciencesUniversity of Tsukuba
  • Pengcheng Zhang
    • Graduate School of Life and Environmental SciencesUniversity of Tsukuba
  • Song Gu
    • Northwest Plateau Institute of BiologyChinese Academy of Sciences
  • Haihua Shen
    • National Institute for Environmental Studies
  • Takeo Kuriyama
    • Department of Biology, Faculty of ScienceToho University
  • Yingnian Li
    • Northwest Plateau Institute of BiologyChinese Academy of Sciences
  • Yanhong Tang
    • National Institute for Environmental Studies
JPR Symposium Carbon cycle process in East Asia

DOI: 10.1007/s10265-010-0315-8

Cite this article as:
Hirota, M., Zhang, P., Gu, S. et al. J Plant Res (2010) 123: 531. doi:10.1007/s10265-010-0315-8

Abstract

Characterizing the spatial variation in the CO2 flux at both large and small scales is essential for precise estimation of an ecosystem’s CO2 sink strength. However, little is known about small-scale CO2 flux variations in an ecosystem. We explored these variations in a Kobresia meadow ecosystem on the Qinghai-Tibetan plateau in relation to spatial variability in species composition and biomass. We established 14 points and measured net ecosystem production (NEP), gross primary production (GPP), and ecosystem respiration (Re) in relation to vegetation biomass, species richness, and environmental variables at each point, using an automated chamber system during the 2005 growing season. Mean light-saturated NEP and GPP were 30.3 and 40.5 μmol CO2 m−2 s−1 [coefficient of variation (CV), 42.7 and 29.4], respectively. Mean Re at 20°C soil temperature, Re20, was −10.9 μmol CO2 m−2 s−1 (CV, 27.3). Re20 was positively correlated with vegetation biomass. GPPmax was positively correlated with species richness, but 2 of the 14 points were outliers. Vegetation biomass was the main determinant of spatial variation of Re, whereas species richness mainly affected that of GPP, probably reflecting the complexity of canopy structure and light partitioning in this small grassland patch.

Keywords

Ecosystem CO2 fluxEcosystem structure and functioningSpatial heterogeneitySpecies richnessQinghai-Tibetan plateau

Copyright information

© The Botanical Society of Japan and Springer 2010