基于动态网络二阶段DEA模型的洞庭湖区耕地利用效率研究

在人口增长与农业可持续发展背景下研究耕地利用效率。以湖南省洞庭湖区为例，以县域为研究单元，运用动态网络二阶段DEA模型，测算2017—2019年洞庭湖区21个县（市、区）耕地利用效率，分析其时空演变特征，借助Pearson相关性模型和Tobit回归模型探析耕地利用效率在不同阶段之间的相互关系及其外部影响机制。结果表明：1)2017—2019年洞庭湖区域21县（市、区）耕地利用系统效率整体呈现先下降后上升的趋势。其中，多数地区生产阶段效率呈现先上升再下降态势；消费阶段效率值呈稳步上升趋势。2）从全局来看，洞庭湖地区耕地系统效率与消费阶段效率呈现东高西低，南高北低态势，耕地生产阶段效率呈现东高西低，北高南低态势。从局部看，各效率值均呈高低集聚分布态势，空间极化现象较为突出。相关分析结果表明消费阶段对系统效率影响更大（0.861）。3）系统及不同子阶段效率的外部影响因素不尽相同，涉及经济社会状况、城乡发展水平、农业基础设施建设和自然条件等。综上，本研究构建动态网络二阶段DEA模型，并探究外部因素对系统及不同子阶段的影响机制，可为耕地高质高效发展提供科学依据。

Cultivated land utilization efficiency in Dongting Lake area: Based on a dynamic network two-stage DEA model

The aim of this study was to study the efficiency of cultivated land utilization under the background of rapid population growth. Taking Dongting Lake area of Hunan Province as an example, based on a dynamic network two-stage DEA model, the efficiency of cultivated land utilization of 21 counties(cities or districts)from 2017 to 2019 was measured, and its spatial-temporal characteristics were analyzed. Pearson correlation model and Tobit regression model were adopted to study the relationship between cultivated land utilization efficiency at different stages and its external influencing factors. The results show that: 1)From 2017 to 2019, the systemic efficiency of cultivated land utilization of 21 counties(cities and districts)in Dongting Lake area display a upward trend at first and a downward trend after, and the efficiency of production stage increases first and then decreased in most areas. The efficiency value in consumption stage shows a steady upward trend. 2)From the global perspective, the efficiency of cultivated land utilization system and consumption stage in Dongting Lake area show the trends of high in the east and low in the west, and high in the south and low in the north; The efficiency of cultivated land production stage is high in the east and low in the west, high in the north and low in the south. From the local perspective, the spatial polarization phenomenon is more prominent. Comparatively, the consumption stage has a greater impact on systemic efficiency with correlation coefficients of 0. 861. 3)The external influencing factors of the efficiency values of the system and different sub-stages are different, involving economic and social conditions, urban and rural development level, agricultural infrastructure construction, natural conditions, etc. In conclusion, the utilization of cultivated land should be regarded as a system. The dynamic two-stage DEA model constructed in this study can measure the efficiency of the utilization of cultivated land in Dongting Lake area at different periods and stages, depict the spatial-temporal differentiation patterned, and explore the influence mechanism of external factors on the system. This study can provide a scientific basis for the efficient and high-quality development of cultivated land.