基于两维图论聚类的辽宁省土地利用多功能性分区

辽宁省土地利用功能间的矛盾相对突出,明晰区域土地利用多功能的现状、进行土地利用多功能性分区可为促进区域土地利用功能的协调发展提供依据。选取2017年辽宁省县域土地利用生活、生产、生态方面22个典型指标构建区域土地利用多功能性评价指标体系,运用熵权法和两维图论聚类法进行土地利用多功能性评价及分区研究。研究发现:1)研究区生活功能高值区于中部呈斜"X"状分布,生产功能值主要呈现以沈阳为中心的"环状"递减蔓延结构,生态功能值由外至内逐渐减少。2)区域县域生产功能和生活功能呈显著正相关,生产功能和生态功能呈显著负相关。3)根据区域土地利用多功能值和两维图论聚类法可将研究区划分为辽东生态功能优势区、辽北功能欠协调区、辽南功能相对均衡区以及辽西功能欠发展区。研究结果可为县域尺度国土空间规划的制定与实施等提供技术支撑和科学依据。

Graph-theoretic clustering for zoning of multifunctional land use in Liaoning Province, China

Unbalanced land use and multifunctionality have posed a great challenge in Liaoning Province, northeast China. There is an urgent need to conduct a multifunctional evaluation system for regional land use, particularly on zoning assessment. In this study, 22 typical indicators were selected from the three aspects of land use, including living, production, and ecology function. An entropy weighting method was applied to calculate the weights of indicators, and then to obtain the mean values of land use life, production, and ecological function in the study area in 2017. A two-dimensional graph-theoretic clustering method was used to integrate the spatial connectivity and indicator similarity between the zoning units. In a weighted connectivity vectorless map G = (V, E, D), the clustering data was achieved using a graph-theoretic minimal tree method. According to the main functional area planning, an optimal construction of each zoning district was proposed for spatial planning in county-level land. The research shows that: 1) The Pearson correlation coefficient of living function and production function was 0.343, whereas, that of production function and ecological function was -0.518. There was no significant correlation between living function and ecological function. 2) The high-value areas of living function were mainly distributed in an oblique "X" shape in the middle of Liaoning province, with low functional values on the east and west areas. There was no significant spatial autocorrelation of living function. The production function value presented a ring-shaped distribution in the center of Shenyang city, while decreased gradually from the center to the edge areas. In the production function, there was a positive and weak autocorrelation with high-high aggregation in the middle, while low-low aggregation in the east. High-value areas of ecological function were mostly distributed in the east and west areas, indicating the function value decreased gradually from the outside to the inside. In the ecological function, there was a positive and strong autocorrelation with high-high aggregation in the east, and a low-low aggregation in the middle. 3) According to the multifunctional features of land use, the study area was divided into, a) the east, the demonstration area of ecological function, b) the north, the function less coordination area, c) the south, the relatively balanced area, and d) the west, the function less development area. The east of Liaoning Province can be strengthened in the construction of public service facilities and economic development. Much attention can be paid to the development of inferior functions in the functional undercoordinated area of northern Liaoning, in order to achieve the goal of coordinated development. In the south of Liaoning, the spatial structure of land use can be optimized in the relatively balanced functional area, thereby to improve the land use function and competitiveness. In the west of Liaoning, the regional advantages can be enhanced in the underdeveloped functional areas, to gradually strengthen the function of land use.