Changes in the soil organic carbon balance on China\u2019s cropland during the last two decades of the 20th century

F Zhang,L Tang,Z Wang,Q Y Liu,C S Li,Y P Wu,S Frolking,S Glidden

doi:10.1038/s41598-017-07237-1

Abstract

Agro-ecosystems play an important role in regulating global changes caused by greenhouse gas emissions. Restoration of soil organic carbon (SOC) in agricultural soils can not only improve soil quality but also influence climate change and agronomic productivity. With about half of its land area under agricultural use, China exhibits vast potential for carbon (C) sequestration that needs to be researched. Chinese cropland has experienced SOC change over the past century. The study of SOC dynamics under different bioclimatic conditions and cropping systems can help us to better understand this historical change, current status, the impacts of bioclimatic conditions on SOC and future trends. We used a simulation based on historical statistical data to analyze the C balance of Chinese croplands during the 1980s and 1990s, taking into account soil, climate and agricultural management. Nationwide, 77.6% of the national arable land is considered to be in good condition. Appropriate farm management practices should be adopted to improve the poor C balance of the remaining 22.4% of cropland to promote C sequestration.

Highlights

As a result of the global effects of anthropogenic activities[1], such as the sharp increase in atmospheric C pools[2,3,4], that greatly impact climate change[5], people are considering feasible and effective ways to mitigate the impacts of these activities
Studies based on soil surveys and regional simulations indicate that from the 1930s to the 1980s, there was a slight decrease in nationwide soil organic carbon (SOC) storage in China[19, 20]
We compiled data on SOC changes to analyze the regional C balance of Chinese cropland and its dynamics based on actual reproduction according to the DNDC scenario during the 1980s and into the 1990s

Summary

Introduction

As a result of the global effects of anthropogenic activities[1], such as the sharp increase in atmospheric C pools[2,3,4], that greatly impact climate change[5], people are considering feasible and effective ways to mitigate the impacts of these activities. 6.2% annual increase in fertilization from 1981 to 2000 increased the annual growth of crop production by 20%21 (www.fao.org/statistics/en). These management measures began to reverse the decline in SOC, and SOC began to accumulate due to the reform of agricultural technology in the 1990s22. Studies have shown that the changes in SOC on Chinese cropland have been influenced by the climate and crop management[18]. Research into SOC change in different types of agro-ecosystems, such as in the midwestern dry-farming area of China, can be used to evaluate differences in bioclimatic conditions and cropping systems and their effects, thereby contributing to our understanding of the impacts of cropland management on SOC. We compiled data on SOC changes to analyze the regional C balance of Chinese cropland and its dynamics based on actual reproduction according to the DNDC (denitrification-decomposition model) scenario during the 1980s and into the 1990s

Methods

Results

Conclusion