西北地区县域生态系统服务的供需匹配——以甘肃古浪县为例

作为人类福利的源泉,生态系统服务的供需特征及匹配状况反映了区域生态与环境资源的空间配置,分析其供需匹配关系是评价与优化生态系统服务管理、促进生态系统服务供需平衡的重要前提。以西北地区河西走廊东端的古浪县为例,利用气象观测、土地利用、统计年鉴等多源数据,基于InVEST模型、ArcGIS等方法,分析古浪县2017年的产水、碳固持、食物供给和土壤保持四项生态系统服务的供需及其匹配状况。结果表明：（1）古浪县产水、碳固持、食物供给和土壤保持服务供给与需求的总量均表现出供大于求的状态,其供求总量差值依次为：12.45×10⁸ m³、21.55×10⁷ t、3.8×10⁷ t、1.28×10⁷ t,且不同类型的生态系统服务供给与需求存在明显差异。（2）古浪县各项生态系统服务供需匹配类型可划分为高供给高需求、低供给高需求、低供给低需求、高供给低需求,不同区域与不同生态系统服务间的匹配模式存在明显的空间异质性。（3）古浪县生态系统服务供需匹配表现出南中北空间差异性,且呈现集中连片的态势,说明匹配类型相同的乡镇存在“相邻相似”的特征。基于对生态系统服务的供给、需求及匹配状况的分析,进一步提出了不同匹配类型下生态经济发展、城镇化建设、生态可持续化管理、国土空间规划等方面的优化对策。

Supply-demand matching of county ecosystem services in Northwest China: A case study of Gulang county

As the source of human welfare, the spatial distribution characteristics and matching status of ecosystem service supply and demand can reflect the spatial allocation of regional environmental resources. Analyzing the matching relationship between supply and demand is an important prerequisite for evaluating and optimizing the management of ecosystem services and promoting the balance between supply and demand of ecosystem services. Taking Gulang county located in the Hexi Corridor as an example, this paper uses multi-source data such as meteorological observation, land use, and statistical yearbooks to evaluate the supply and demand of four ecosystem services including water supply, carbon sequestration, food supply and soil conservation, based on InVEST model and ArcGIS method. Result shows that: (1) The total supply and demand of ecosystem services in this county indicate that supply exceeds demand, and there are obvious differences among different types of ecosystem services. Besides, the total difference between supply and demand water for supply, carbon sequestration, food supply, and soil conservation is 12.45×10⁸ m³, 21.55×10⁷ t, 3.8×10⁷ t, and 1.28×10⁷ t, respectively. (2) Based on the township unit, the supply and demand matching of various ecosystem services in the study area are presented as four types (high supply and high demand, low supply and high demand, low supply and low demand, and high supply and low demand), and the matching patterns between regions and ecosystem services have obvious spatial heterogeneity. (3) The four matching types generally show the hierarchical division of the south, the middle and the north, and present the centralized and continuous patterns, which indicates that the towns with the same matching types are characterized by "adjacent similarity". Based on the analysis of the supply, demand and matching status of ecosystem services, this paper puts forward the optimization countermeasures of eco-economic development, urbanization construction, sustainable ecological management and land spatial planning under different matching types.