Ecological Indicators (May 2022)
Value compensation of net carbon sequestration alleviates the trend of abandoned farmland: A quantification of paddy field system in China based on perspectives of grain security and carbon neutrality
Abstract
Farmland abandonment is threatening the grain security in China. The phenomenon also impeded the contribution of carbon sequestration from grain cultivation system. Recently, people are discussing a valuable joint point between the issues: if the value of carbon sequestration in grain production system would be compensated to the grain producers, the increased income would possibly improve the farmers’ initiative of producing grain, alleviating the trend of abandoned farmland and promoting the development of low-carbon agricultural system in China at the same time. Therefore, this study selected the rice production system in Guangdong province in China as a case to quantify the value of net carbon sequestration of the system and assessed the grain security situation. The case was expected to comprehensively discuss the dual significances of grain cultivation in ensuring food security and promoting GHGs emission reduction. The results demonstrated that the rice yield, sown area and rice self-sufficiency rate decreased significantly in Guangdong province during 2000–2019. The self-sufficiency rate of rice in Guangdong province was only about 22% currently, presenting serious crisis on grain security in this region. Meanwhile, this study found that the greenhouse gas emissions from rice production system in Guangdong province reached 193.68 million tons CO2 and 206.00 million tons CO2 at farmland level and the life cycle level, respectively. The quantity of net carbon sequestration from the rice cultivation system was 96 million tons/yr, which was estimated to be 2.29 billion yuan/yr at the farm level and 2.22 billion yuan/yr at the life cycle level, respectively, based on the average price of carbon trading. Consequently, this study raised that the compensation standards for carbon neutrality of rice planting should be 2147.84 yuan/ha at the farm level and 1235.24 yuan/ha at the life cycle level, respectively. This study proposed that scientific and feasible value compensation of net carbon sequestration of grain production would alleviate the trend of abandoning farmland, contributing to the win-win situation of grain security and carbon neutrality targets in China. This study could provide a research basis for decision making in China and other nations to stabilize grain production by the carbon compensation policy of farmland.
