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由温室气体排放引起的全球变暖问题已受到公众的广泛关注。农业生产对温室气体排放有重要影响,水稻是中国主要粮食作物,而稻田又是CH_4的主要排放源,因此研究其生产过程的碳足迹对实现农业节能减排具有意义。本研究基于2004-2014年水稻生产相关统计数据,利用碳足迹评价方法核算了中国水稻生产碳足迹及其变化趋势。研究结果表明:①中国水稻生产温室气体排放量、单位面积碳足迹呈逐年增长,而单位产量碳足迹则出现下降趋势,年均增长量分别为21.24亿kgCO_2-eq、32.58kgCO_2-eq/hm~2和-2.82kgCO_2-eq/t;②不同省份由于水稻生产条件差异,其碳足迹存在较大差别,如年均单位面积碳足迹最高的江苏达7411.91kgCO_2-eq/hm~2,最低的黑龙江为4305.87kgCO_2-eq/hm~2;③年均单位产量碳足迹方面,最高海南为1419.35kgCO_2-eq/t,最低吉林为602.12kgCO_2-eq/t;④综合比较单位面积与单位产量碳足迹发现,华南双季稻稻作区(广西、广东、福建等),华中双季稻稻作区(江苏、湖南、江西等),其单位碳足迹均高于全国平均水平;⑤水稻生产碳足迹组成中占比最大的部分为稻田CH_4排放,达85.05%,农资投入导致的温室气体排放仅占14.95%,其中化肥投入占总碳足迹的10.25%。最后,本文建议通过改进农田管理措施(如间歇性灌溉、改进施肥、合理使用农业投入品),提高水稻机械化生产效率来有效减少水稻温室气体排放。
The issue of global warming caused by greenhouse gas emissions has received widespread public attention. Agricultural production has an important impact on greenhouse gas emissions. Rice is a major food crop in China, and paddy fields are the main sources of CH4 emissions. Therefore, it is of great significance to study the carbon footprint of the production process to achieve energy saving and emission reduction in agriculture. Based on the statistics of rice production from 2004 to 2014, this study calculated the carbon footprint of rice production in China and its changing trend by using carbon footprint assessment method. The results show that: (1) The carbon footprint per unit area of rice production in China has been increasing year by year, while the carbon footprint per unit of output has been on a downward trend with an average annual growth of 2.124 billion kgCO 2 -eq and 32.58 kgCO 2 -eq / hm ~ 2 and -2.82kgCO 2 -eq / t, respectively. ② Because of different rice production conditions in different provinces, there is a big difference in their carbon footprint. For example, Jiangsu with the highest annual carbon footprint of 7411.91kgCO 2 -eq / hm 2 and the lowest Heilongjiang The highest in Hainan was 1419.35kgCO_2-eq / t and the lowest in Jilin was 602.12kgCO_2-eq / t; ④A comprehensive comparison of carbon footprint per unit area and unit yield was found , South China Double Cropping Rice Paddy Fields (Guangxi, Guangdong and Fujian), and Central China Double Cropping Rice Paddy Cropping Areas (Jiangsu, Hunan and Jiangxi) with their unit carbon footprint above the national average; The largest part is CH_4 emissions from paddy fields, accounting for 85.05%. Only 14.95% of greenhouse gas emissions from agricultural inputs are made, of which 10.25% of total carbon footprint is contributed by fertilizers. Finally, this paper proposes to reduce greenhouse gas emissions from rice by improving farmland management practices (such as intermittent irrigation, improving fertilization, rationalizing the use of agricultural inputs) and increasing the efficiency of mechanized rice production.