黄河流域城市群土地利用及生态效率时空演变分析

黄河流域城市土地资源的合理高效利用和生态环境的治理可加强其生态保护和高质量发展进程，有效测度城市土地利用及生态效率至关重要。基于随机前沿分析（Stochastic Frontier Analysis，SFA）模型测算黄河流域7个城市群59个城市的土地利用效率（Land Use Efficiency，LUE）、生态绩效指数（Ecological Performance Index，EPI）和生态效率（Ecological Efficiency，EE），探究其时空变化规律并进行空间自相关分析。结果表明：对比分析非约束模型与约束模型的结果可知，加入生态变量后的LUE平均值增加4.43%。黄河流域城市群LUE年平均值为0.89，多数城市LUE呈增加趋势，空间上呈现出西低东高的分布特征；EPI大于0的城市占比90%以上，其对土地利用效率有正向贡献；城市群EE年平均值为0.62，在空间上呈现出西高东低的分布格局，并存在显著正向的空间聚集格局特征；EE与LUE呈U型关系变化，LUE随EE增大呈现出先降低后提升的变化趋势。未来黄河流域应提高资源利用强度，优化资源配置，深化城市群跨区域交流合作，注重城市生态效率提升，构建高质量发展大格局。

Spatio-temporal evolution of land use and eco-efficiency in urban agglomerations in the Yellow River Basin

The rational and efficient use of urban land resources and ecological environment management can strengthen the ecological protection and high-quality development process in the Yellow River Basin. Therefore, it is crucial to effectively measure urban land use efficiency and eco-efficiency. Based on Stochastic Frontier Analysis (SFA) model, this study measures the Land Use Efficiency (LUE), Ecological Performance Index (EPI) and Ecological Efficiency (EE) of 59 cities in 7 urban agglomerations in the Yellow River Basin and analyzes their spatial and temporal variation patterns from 2005 to 2018. Then, this study conducts the spatial autocorrelation analysis of LUE and EE, and further explores the relationship between LUE and EE. The results of this study show that the mean land use efficiency increases by 4.43% after the addition of ecological variables when comparing the test results of the unconstrained model with those of the constrained model. The mean value of land use efficiency of the urban agglomerations in the Yellow River Basin is 0.89, and most cities show an increasing trend of land use efficiency, with the spatial distribution characteristic of low in the west and high in the east. The percentage of cities with ecological performance index greater than 0 is more than 90%, indicating that the addition of ecological variables contributes to the improvement of land use efficiency of most cities in the Yellow River Basin. The annual mean value of ecological efficiency of urban agglomerations in the Yellow River Basin is 0.62, which shows a spatial distribution pattern of high in the west and low in the east, and significantly positively spatial aggregation pattern characteristic. With further analysis, we find that ecological efficiency and land use efficiency change in a U-shaped relationship, indicating that land use efficiency shows a trend of first decreasing and then increasing with the increasing ecological efficiency. This study reveals the relationship among urban land use, ecological benefits and social-economic effects in the urban agglomerations of the Yellow River Basin, which can provide a reference for the development of new urbanization, efficient use of land resources, ecological protection and high-quality development in the Yellow River Basin. Based on the empirical analysis results, we suggest that the Yellow River Basin is supposed to improve the intensity of resource utilization, optimize the allocation of various resources for cities in the basin, deepen cross-regional exchanges and cooperation among different urban agglomerations and cities, focus on the improvement of urban ecological efficiency, and build a high-quality development pattern in the future.