Acta Geographica Sinica ›› 2016, Vol. 71 ›› Issue (1): 21-34.doi: 10.11821/dlxb201601002

• Ecology and Environment • Previous Articles     Next Articles

Spatial-temporal features of carbon source-sink and its relationship with climate factors in Inner Mongolia grassland ecosystem

DAI Erfu1,2(), HUANG Yu3, WU Zhuo1,2,4, ZHAO Dongsheng1,2   

  1. 1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    2. Key Laboratory of Land Surface Pattern and Simulation, CAS, Beijing 100101, China
    3. School of Planning, Faculty of Environment, University of Waterloo, Waterloo ON N2L 3G1, Canada
    4. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2015-06-23 Revised:2015-10-18 Online:2016-01-31 Published:2016-01-15
  • Supported by:
    National Basic Research Program of China (973 Program), No.2015CB452702, No.2012CB416906;National Natural Science Foundation of China, No.41571098, No.41371196;National Key Technology R&D Program, No.2013BAC03B04

Abstract:

In this paper, field sampling data, remote sensing data, and ground meteorological observation data were used to estimate the net primary productivity (NPP) in the grassland ecosystem in Inner Mongolia from 2001 to 2012 based on a light use efficiency model. The spatiotemporal distribution of the NEP in the Inner Mongolia grassland ecosystem was then analyzed by estimation of the NPP and soil respiration from 2001 to 2012. This paper also investigated the response of the NPP and NEP to main climatic variables on the spatial and temporal scales from 2001 to 2012. Results showed that most of the grassland area in Inner Mongolia has functioned as a carbon sink since 2001 and that the annual carbon sequestration rate amounts to 0.046 Pg C·yr-1. The total net carbon sink of the Inner Mongolia grassland ecosystem over the 12-year period reached 0.557 Pg C. The carbon sink area accounted for 60.28% of the total grassland area and sequestered 0.692 Pg C, whereas the C source area accounted for 39.72% of the total grassland area and released 0.135 Pg C. The NPP and NEP of the Inner Mongolia grassland ecosystem have more significant correlations with precipitation than with temperature, and the Inner Mongolia grassland ecosystem has great potential for carbon sequestration.

Key words: grassland ecosystem, NPP, NEP, carbon source-sink, Inner Mongolia