Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (9): 1322-1332.DOI: 10.17521/cjpe.2023.0001

Special Issue: 全球变化与生态系统 生态系统碳水能量通量

• Data Paper • Previous Articles    

A dataset of ecosystem fluxes in a shrubland ecosystem of Mau Us Sandy Land in Yanchi, Ningxia, China (2012-2016)

HAN Cong1, MU Yan-Mei1, ZHA Tian-Shan1,2, QIN Shu-Gao1,2, LIU Peng1,2, TIAN Yun1,2, JIA Xin1,2,*()   

  1. 1Yanchi Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
    2Key Laboratory of State Forestry and Grassland Administration on Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
  • Received:2023-01-02 Accepted:2023-03-06 Online:2023-09-20 Published:2023-09-28
  • Contact: * JIA Xin(xinjia@bjfu.edu.cn)
  • Supported by:
    National Ecosystem Science Data Center(NESDC20210101);National Natural Science Foundation of China(32071843);National Natural Science Foundation of China(32101588);National Natural Science Foundation of China(32071842);National Natural Science Foundation of China(31901366);Fundamental Research Funds for the Central Universities(PTYX202122);Fundamental Research Funds for the Central Universities(PTYX202123)

Abstract:

Arid and semi-arid ecosystem areas, which constitute an important component of the global land surface, act to regulate the long-term trend and interannual variations in global carbon and water cycles. Previous studies on the mechanisms underlying ecosystem carbon and water cycling and the development of relevant data products focus primarily on forest, grassland, and cropland ecosystems, with few research attention given to semi-arid shrublands. This research gap hinders the evaluation and projection of ecosystem functions at the regional scale. Since 2011, we used the eddy covariance technique to make continuous in situ measurements of carbon, water and heat fluxes in a shrubland ecosystem at Yanchi Research Station, the Mau Us Sandy Land. Data processing steps mainly included data collection, post-processing of raw data, quality control, gap-filling and carbon flux partitioning. We produced flux and micro-meteorological datasets at half-hourly, daily, monthly, and annual temporal resolutions for the years 2012-2016, and analyzed the overall quality of the datasets in terms of the proportion of valid data and the energy balance closure of flux measurements. Results showed: (1) After quality control, the proportion of valid data for half-hour net ecosystem CO2 exchange (NEE), latent heat flux (LE), and sensible heat flux (Hs) was 56.23%-62.19%, 79.40%-94.12%, and 77.56%-91.27%, respectively. (2) Annual and monthly energy balance ratio ranged 0.78-0.83 and 0.59-1.19, respectively. (3) The energy balance closure estimated using the “ordinary least squares” regression method showed that the interannual and seasonal variations in the slope of regression curves varied with a range of 0.73-0.79 at interannual scale and 0.73-0.92 at seasonal scale, respectively. These results indicate that our datasets have a high proportion of valid data and a reasonable energy balance closure, and thus can be used in studies related to ecosystem processes and functions at varing spatio-temporal scales.

Key words: cabon and water fluxes, energy balance, eddy covariance, Mau Us Sandy Land, semi-arid shrubland