Organic Carbon Sequestration Potential and the Co-Benefits in China’s Cropland - Principles of Sustainable Soil Management in Agroecosystems - page 516

In conclusion, SOC sequestration is a matter not of an increase in soil's OM con-
tent but of the increase in soil's capacity to act in an integrated and interactive man-
ner for cropland productivity and ecosystem health. Therefore, SOC sequestration in
China's croplands should be given much more attention than ever before when food
safety and ecological sustainability are at stake.

18.5 CONCLUSION
There have been many studies on estimating the SOC pools, storage, and the changes
due to land use and land use changes of China's soils. It has become clear that China's
soils have been relatively depleted of OM and thus have a great potential to sequester
carbon for climate change mitigation in agriculture. However, it is still poorly under-
stood to what extent the biophysical SOC sequestration potential could be realized or
technically attainable with BMPs even under rational incentives within the climate
change policy framework of the state. There have been increasing evidences that
SOC sequestration benefits mitigation and also crop productivity and health, as well
as ecosystem functioning also though the coherent processes and mechanisms are
still unclear. Finally, there has been an urgent need to enhance and stabilize SOM
in China's croplands for ensuring food production and sustainability of farming sys-
tems of the country.

ACKNOWLEDGMENT
This work was partly funded by the Natural Science Foundation of China under
grants 40830528 and 40270010092.

ABBREVIATIONS
BMP:

best management practice

SOC: soil organic carbon

SOM: soil organic matter

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