新疆塔里木河流域县域农业低碳生产率时空格局及影响效应研究

Spatial and temporal patterns of agricultural low-carbon productivity and its influence effects in the counties of Tarim River Basin,Xinjiang

提高农业低碳生产率是保证干旱区生态优先和粮食安全的有效路径。基于非期望产出的超效率考虑松弛变量的测度(Slacks-based measure,SBM)模型测度2000—2020年新疆塔里木河流域42个县(市)的农业低碳生产率,利用趋势面分析及空间自相关刻画县域尺度农业低碳生产率的时空特征,并通过构建空间杜宾模型和地理探测器以揭示影响变量的溢出效应与空间异质性。结果表明:(1)塔里木河流域县域农业低碳生产率呈现“W型”的阶段性特征,县域之间形成“下游-上游-中游”凹形递减的分异格局,且在空间上呈现出集聚性。(2)机械化使用强度和农民收入水平对县域农业低碳生产率具有显著的正向溢出效应;人口城镇化水平对县域农业低碳生产率具有显著的负向溢出效应;工业化水平和财政支农力度对农业低碳生产率具有显著的负向直接效应;经济发展水平和人均生产规模的溢出效应并不显著。(3)县域农业低碳生产率影响变量的交互类型总体表现为增强型,意味着县域农业低碳生产率受多重变量作用的趋势日益显现。因此,探究县域农业低碳生产率的时空格局及影响因素对实现塔里木河流域乃至新疆农业低碳化协调发展具有重要意义。

Improving low-carbon productivity in agriculture is an effective path to ensure ecological priority and food security in arid areas.In this study,a super-efficient SBM model based on nonexpected output is used to measure the agricultural low-carbon productivity of 42 counties(cities)in the Tarim River Basin of Xinjiang,Chi-na from 2000 to 2020.The model uses trend surface analysis and spatial autocorrelation to portray the spatial and temporal characteristics of agricultural low-carbon productivity at the county scale,and constructs a spatial Durbin model and a geographic detector to reveal the spillover effects of influencing variables and spatial hetero-geneity.The results show that:(1)The low-carbon productivity of agriculture in the Tarim River Basin shows a“W-shaped”stage,with a concave decreasing pattern of“downstream-upstream-midstream”between counties,and a spatial clustering.(2)Mechanization intensity and farmers’income level have significant positive spillover effects on low-carbon productivity in county agriculture;population urbanization has significant negative spill-over effects on low-carbon productivity in county agriculture;industrialization level and financial support to agri-culture have significant negative direct effects on low-carbon productivity in agriculture;and the spillover effects of economic development level and per capita production scale are not significant.(3)The interaction type of the low-carbon productivity impact variables in county agricultural shows an enhanced type in general,implying the trend that low-carbon productivity in county agriculture is increasingly influenced by multiple variables.There-fore,it is important to explore the spatial and temporal patterns of low-carbon productivity in county agriculture and the influencing factors to achieve a coordinated development of low-carbon agriculture in the Tarim River Ba-sin and even in Xinjiang.