河北省耕地集约利用水平与碳排放效率的相关性

Correlation between levels of cultivated land intensive use and carbon emission efficiency in Hebei Province

为探索不同耕地集约利用水平下的碳排放效率变化规律,更好实现耕地集约利用的社会效益和生态效益,该文分别构建了耕地集约利用模型和数据包络分析模型,运用GIS(geographic information system)空间分析技术分析了河北省138个县(市)耕地集约利用度和耕地碳排放效率时空变异特征,在此基础上探索了耕地集约利用与碳排放综合效率的空间聚集差异特征。研究结果表明:河北省耕地集约利用水平呈现由平原区向山地丘陵再向坝上高原区扩展的趋势;碳排放综合效率有效区域集中分布于坝上高原与山地丘陵区,而石家庄、邢台和经济发展较好的唐山等地区碳排放综合效率较低;耕地集约利用度和碳排放综合效率空间分布上总体呈现负相关性,且随着时间推移局部聚集效应呈现不断增强的态势。

The investigation on carbon dioxide emission efficiency is essential in achieving the environmental and ecological benefits of cultivated land intensive use. However, the specific investigation of the relationship between cultivated land intensive use and carbon dioxide emission efficiency is still limited, especially in the provincial scale. Therefore, the research explored the variation law of carbon dioxide emission efficiency under cultivated land intensive use of different levels in Hebei Province, owing to its essential geographical position in the food security and economic development of the Beijing-Tianjin-Hebei Metropolitan Region. The main methods included the construction of the model of cultivated land intensive use and the model of data envelopment analysis （DEA）. The indices were chosen from input （labor, capital and technology per agricultural acreage） and output. As carbon emission was considered as the cost, the agricultural added value, grain production and family business income per unit carbon dioxide emission were determined as output indices. GIS （geographic information system） spatial analysis was adopted to investigate the level of cultivated land intensive use and the features of the temporal and spatial variation of carbon dioxide emission efficiency in 138 counties （cities） in Hebei Province. Exploratory spatial data analysis （ESDA） and Moran scatter diagram were adopted to measure the aggregation degree of cultivated land intensive use and carbon dioxide emission efficiency. On the basis above, the research investigated the features of spatial clustering difference of cultivated land intensive use and total carbon dioxide emission efficiency, and analyzed the variation law of carbon dioxide emission efficiency under cultivated land intensive use of different levels. The results were as follows： 1） The level of cultivated land intensive use in Hebei Province presented the expanding trend from plain to mountain and from hill to Bashang Plateau. 2） The effective areas of total carbon dioxide emission efficiency were mainly centered on the Bashang Plateau and mountain and hill areas, while the total carbon dioxide emission efficiency was relatively low in developed areas such as Shijiazhuang, Xingtai and Tangshan, because of the insufficient utilization of input and the consequent failure of restricting the scale of carbon dioxide emission during the increase of grain production and agricultural added value. 3） Inverse association was presented between the level of cultivated land intensive use and the total carbon dioxide emission efficiency spatially, and the local aggregation effect was constantly reinforced over time. Most areas showed HL （high cultivated land intensity use – low carbon dioxide emission efficiency） clustering and LH （low cultivated land intensity use – high carbon dioxide emission efficiency） clustering, indicating the necessity of investigating the relationship between cultivated land intensive use and carbon emission optimization. The risk of over intensive use existed in the areas of HL clustering, which demanded the protection of ecological benefit. The ecological vulnerability was the bottleneck of the areas of LH clustering, and therefore, its priority should be guaranteed during the optimization of resource utilization. Owing to the limitation of reserved cultivated land resources, the carbon emission should be emphasized during the land resource management in Shijiazhuang City, Tangshan City, Qinhuangdao City, Langfang City and Chengde City. Relatively, Baoding City and Handan City owned sufficient reserved cultivated land resources, thus demanding comprehensive land improvement.