Science in China Series D: Earth Sciences
SCIENCE IN CHINA PRESS
www.scichina.com www.springerlink.com Sci China Ser D-Earth Sci | Sep. 2007 | vol. 50 | no. 9 | 1341-1350
Terrestrial vegetation carbon sinks in China, 1981―
, GUO ZhaoDi, PIAO ShiLong & CHEN AnPing
Department of Ecology, College of Environmental Science, and Key Laboratory for Earth Surface Processes of the Ministry of
Education, Peking University, Beijing 100871, China
Using China’s ground observations, e.g., forest inventory, grassland resource, agricultural statistics,
climate, and satellite data, we estimate terrestrial vegetation carbon sinks for China’s major biomes
between 1981 and 2000. The main results are in the following: (1) Forest area and forest biomass car-
bon (C) stock increased from 116.5×10
ha and 4.3 Pg C (1 Pg C = 10
g C) in the early 1980s to
ha and 5.9 Pg C in the early 2000s, respectively. Forest biomass carbon density increased
form 36.9 Mg C/ha (1 Mg C = 10
g C) to 41.0 Mg C/ha, with an annual carbon sequestration rate of 0.075
Pg C/a. Grassland, shrub, and crop biomass sequestrate carbon at annual rates of 0.007 Pg C/a, 0.014―
0.024 Pg C/a, and 0.0125―0.0143 Pg C/a, respectively. (2) The total terrestrial vegetation C sink in China
is in a range of 0.096―0.106 Pg C/a between 1981 and 2000, accounting for 14.6%―16.1% of carbon
) emitted by China’s industry in the same period. In addition, soil carbon sink is estimated
at 0.04―0.07 Pg C/a. Accordingly, carbon sequestration by China’s terrestrial ecosystems (vegetation
and soil) offsets 20.8%―26.8% of its industrial CO
emission for the study period. (3) Considerable
uncertainties exist in the present study, especially in the estimation of soil carbon sinks, and need
further intensive investigation in the future.
carbon sink, China, crops, forests, grasslands, shrubs, soils, terrestrial ecosystems
Global and regional carbon cycles are one of the key
issues in global change research. Estimating the size of
carbon sinks or sources and their spatial and temporal
patterns is not only of scientific importance, but also
attracts widespread public attention because it is closely
related with the ambitious Kyoto Protocol which aims at
reducing fossil fuel emissions to the atmosphere.
Generally, if an ecosystem fixes more carbon than it
emits, then this ecosystem will function as a sink of at-
, or “carbon sink”. In contrast, it acts as
“carbon source” when its emission exceeds its absorp-
tion. Comprehensive assessment on size and distribution
of terrestrial ecosystem carbon sources/sinks has been
available for a few western industrial countries. For
example, Pacala et al.
found that North American ter-
restrial ecosystems sequestered 30%―50% of its indus-
emissions in the 1980s. Similarly, about 7%―
12% of carbon release from European industry was se-
questered by its terrestrial ecosystems
. Although there
have already been several studies on China’s ecosystem
carbon cycle, most of them have focused on certain
vegetation or soil types, and a complete assessment of
the whole ecosystem has not been conducted. Liu et al.
Fang et al.
and Piao et al.
estimated forest biomass
carbon sink in China. Piao et al.
estimated the size and
spatial distribution of China’s grassland biomass carbon
sink. In terms of soil carbon pools, Pan et al.
Received July 11, 2006; accepted January 19, 2007
Corresponding author (email: firstname.lastname@example.org)
Supported by the National Natural Science Foundation of China (Grant Nos.
90211016, 40638039, 40228001, and 40021101) and the Key MOE Research Project
(Grant No. 306019)