2011—2020年中国大豆生产碳排放效率时空演变及影响因素

Spatio‑temporal evolution of carbon emission efficiency and influencing factors of China's soybean production from 2011 to 2020

准确分析大豆生产碳排放效率与影响因素,可为加快实现大豆生产碳减排提供理论依据与数据支撑。目前,鲜有关于中国大豆生产碳排放效率的研究,且尚未有关于大豆生产碳排放效率影响因素的研究。因此,该研究在选用生命周期评价法核算2011—2020年中国大豆生产全生命周期碳排放量的基础上,采用含有非期望产出的超效率SBM模型测算中国大豆生产碳排放效率,并基于Tobit模型探究影响中国大豆生产碳排放效率的主要因素。结果表明:①大豆生产碳排放总量呈现“上升—下降—上升”的3阶段变化特征,2020年大豆生产碳排放总量较2011年提升了47.70%;2020年单位产值大豆生产碳排放为7.48 t/万元,较2011年的5.64 t/万元增长了32.62%;大豆生产的碳排放强度则由2011年的5.16 t/hm2增至2020年的6.09 t/hm2,增长了18.02%。尽管碳排放整体呈上升趋势,但存在明显的区域差异,其中,黑龙江属于大豆生产碳排放总量大、单位产值碳排放高、碳排放强度高的地区,碳减排压力较大。②大豆生产碳排放效率呈先降后升的演变趋势,均值为0.78。主产区大豆生产碳排放效率空间差异明显,除山西、吉林碳排放效率年均变化率为负,其余地区大豆生产碳排放效率年均变化率均为正,且山西碳排放效率具有较大提升空间。③碳排放效率影响因素分析表明,作物种植结构、财政支农水平、农业机械化水平和农业技术水平对大豆生产碳排放效率具有显著正向作用,农业产业结构和农村劳动力受教育程度对大豆生产碳排放效率具有显著负向作用。建议提高农业机械化水平和财政支农水平,并基于大豆生产碳排放效率的区域异质性分类施策,以推动大豆生产绿色低碳发展,促进农业碳减排。

Accurately analyzing the carbon emission efficiency of soybean production and identifying factors influencing the carbon emission efficiency can be helpful to provide references and a data basis for promoting carbon reduction in soybean production.However,few specific studies on the carbon emission efficiency of China's soybean production have been reported.In particular,no studies on the influencing factors of the carbon emission efficiency of China's soybean production have been conducted.To fill such a research gap,this study evaluated the carbon emissions of China's soybean production from 2011 to 2020 by applying life cycle assessment.Then,the Super-SBM model based on the unexpected output was adopted to measure the carbon emission efficiency of China's soybean production.Finally,the Tobit model was adopted to explore the factors influencing the carbon efficiency of China's soybean production.The results showed that:①The total carbon emissions generated from China's soybean production exhibited a trend of‘increase-decrease-increase,’with an increase of 47.70%from 2011 to 2020.The carbon emissions generated by per RMB 10 thousand yuan soybean production were 7.48 t in 2020,which was 32.62%higher than that in 2011,which was 5.64 t.Meanwhile,the carbon intensity increased from 5.16 t/hm2 in 2011 to 6.09 t/hm2 in 2020,with an increase of 18.02%.The results of this study showed that carbon emissions from soybean production exhibited an upward trend in general,while regional differences existed.For instance,Heilongjiang had higher carbon emissions,higher carbon emissions per value unit output,and higher carbon intensity,posing high stress on carbon emissions reduction.②The carbon emission efficiency of soybean production in China showed an evolution trend of first decreasing and then increasing,with an average value of 0.78.In addition,the spatial difference in carbon emission efficiency in soybean production was obvious.Except for Shanxi and Jilin,the average annual change rate of carbon emission efficiency in other major soybean-producing areas was positive,with Shanxi exhibiting great potential for improving emission efficiency.③The analysis of the influencing factors of carbon emission efficiency showed that crop planting structure,financial support for agriculture,agricultural mechanization,and agricultural technology had significant positive effects on the carbon emission efficiency of soybean production.Meanwhile,agricultural industrial structure and the education level of the rural labor force had significantly negative effects on the carbon emission efficiency of soybean production.Suggestions such as improving agricultural mechanization and financial support for agriculture,and making policies based on the regional heterogeneity of carbon emission efficiency of soybean production are proposed so that green and low-carbon development of soybean production can be achieved and the reduction of carbon emissions in the agricultural sector can be eventually promoted.