基于小流域尺度的县域国土空间生态修复分区——以山西汾河上游为例

Ecological restoration zoning of county-level territorial space based on small watershed scale:A case study of the upper Fenhe River in Shanxi

县域国土空间生态修复是生态修复规划体系的重要一环,也是生态修复工程项目实施的直接上位指导性规划,基于小流域尺度的生态修复分区研究可以为黄土高原地区县域生态修复分区的理论和实践提供有益参考。以汾河上游为例,首先,基于数字高程模型提取地形特征的方法确定了89个小流域单元,进而定量评估水源涵养、水土保持、生物多样性、食物供给四种典型生态系统服务,综合识别区域主导生态功能,据此划定5个生态功能分区;然后,以生态功能分区内生态群落为基础,通过对不同生态群落的生态功能统计比较,划分12个生态修复分区;最后,将小流域合并得到沟域生态系统单元,进而划分了25个生态修复工程分区统筹后期工程项目实施,并提出相应的生态修复策略。本文提出新的生态修复分区思路,以期为县域国土空间生态修复规划的编制提供指引。

Ecological restoration zoning of county-level territorial space is an important part of the ecological restoration planning system and a superior guiding plan for the implementation of ecological restoration projects.The study of ecological restoration zoning based on small watershed scale can provide useful reference for the theory and practice of county ecological restoration zoning in the Loess Plateau Region.In this paper,taking the upper Fenhe River as an example,firstly,89 small watershed units were identified based on the DEM to quantitatively assess four typical ecosystem services,namely water conservation,soil and water conservation,biodiversity and food supply,and to identify the dominant ecological functions and accordingly delineate five ecological function zones.Then,based on the ecological communities within the ecological function areas,12 ecological restoration sub-areas were divided through statistical comparison of the ecological functions of different ecological communities.Finally,the small watersheds were combined to obtain ditch ecosystem units,and then 25 ecological restoration project sub-areas were identified to coordinate the implementation of later projects and propose corresponding ecological restoration strategies.This paper proposes a new idea of ecological restoration zoning,with a view to provide guidance for the preparation of ecological restoration planning in the county-level territorial space.