Spatio-Temporal Patterns and Climate Variables Controlling of Biomass Carbon Stock of Global Grassland Ecosystems from 1982 to 2006
作者:Xia, JZ (Xia, Jiangzhou)[ 1,2 ] ; Liu, SG (Liu, Shuguang)[ 3,4 ] ; Liang, SL (Liang, Shunlin)[ 1,2,5 ] ; Chen, Y (Chen, Yang)[ 6 ] ; Xu, WF (Xu, Wenfang)[ 6 ] ; Yuan, WP (Yuan, Wenping)[ 6,7 ]
REMOTE SENSING
卷: 6  期: 3  页: 1783-1802
DOI: 10.3390/rs6031783
出版年: MAR 2014

摘要
Grassland ecosystems play an important role in subsistence agriculture and the global carbon cycle. However, the global spatio-temporal patterns and environmental controls of grassland biomass are not well quantified and understood. The goal of this study was to estimate the spatial and temporal patterns of the global grassland biomass and analyze their driving forces using field measurements, Normalized Difference Vegetation Index (NDVI) time series from satellite data, climate reanalysis data, and a satellite-based statistical model. Results showed that the NDVI-based biomass carbon model developed from this study explained 60% of the variance across 38 sites globally. The global carbon stock in grassland aboveground live biomass was 1.05 Pg center dot C, averaged from 1982 to 2006, and increased at a rate of 2.43 Tg center dot C center dot y(-1) during this period. Temporal change of the global biomass was significantly and positively correlated with temperature and precipitation. The distribution of biomass carbon density followed the precipitation gradient. The dynamics of regional grassland biomass showed various trends largely determined by regional climate variability, disturbances, and management practices (such as grazing for meat production). The methods and results from this study can be used to monitor the dynamics of grassland aboveground biomass and evaluate grassland susceptibility to climate variability and change, disturbances, and management.

通讯作者地址: Liu, SG (通讯作者)
US Geol Survey, Earth Resources Observat & Sci EROS Ctr, Sioux Falls, SD 57198 USA.
地址:
[ 1 ] Chinese Acad Sci, State Key Lab Remote Sensing Sci, Beijing Normal Univ & Inst Remote Sensing & Digit, Beijing 100875, Peoples R China
[ 2 ] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China
[ 3 ] US Geol Survey, Earth Resources Observat & Sci EROS Ctr, Sioux Falls, SD 57198 USA
[ 4 ] S Dakota State Univ, Geog Informat Sci Ctr Excellence, Brookings, SD 57007 USA
[ 5 ] Univ Maryland, Dept Geog Sci, College Pk, MD 20742 USA
[ 6 ] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China
[ 7 ] Chinese Acad Sci, Cold & Arid Reg Environm & Engn Res Inst, State Key Lab Cryospher Sci, Lanzhou 730000, Peoples R China