城市水土保持区划及功能性评价研究--以宜昌市为例

Urban Soil and Water Conservation Zoning and Basic Function Evaluation:Case Study on Yichang City

目前全国地级市水土保持区划工作滞后,宜昌市作为湖北省域副中心城市,城市水土流失严重。为突出地方特色、因地制宜地指导地方水土保持区划工作的落地实施,以宜昌市为例,在国家、省级水土保持区划成果的基础上,紧密结合宜昌市地方特点,逐步进行细化,形成宜昌市水土保持四级区划,并对区划成果进行基本功能分析评价。宜昌市水土保持区划使用四级分区体系,前三级区划沿用国家水土保持区划中一级、二级、三级分区范围;四级区被分为6个水土保持片区:沿江平原丘陵农田防护区、香溪河山地生态维护区、三峡库区山地丘陵保土区、沮漳河山地丘陵保土区、清江山地水源涵养保土区以及中心城区人居环境维护区。全市共涉及5个水土保持基本功能,分别为农田防护、生态维护、土壤保持、水源涵养和人居环境维护。地级市水土保持区划分区既要在国家、省级水土保持区划基础上进行,同时还需突出地方特点,因地制宜。宜昌市水土流失治理应坚持预防为主,保护水源,并加强水土保持重点监管。

At present,the soil and water conservation zoning work of prefecture-level cities in China is lagging behind.Yichang,as a sub-central city of Hubei Province,is suffering from severe soil and water loss in the city.In the aim of guiding the zoning work for soil and water conservation,we present a four-level division of soil and water conservation for Yichang City as a case study,and evaluated the basic functions of each zone in line with the local conditions based on the results of national and provincial water and soil conservation planning.The soil and water conservation zoning of Yichang City comprises four levels,of which the first three levels follow the national first-level,second-level and third-level zonings.On this basis,the fourth level refines as six sub-zones:the hilly farmland protection zone along the Yangtze River Plain,the mountainous ecological conservation zone along the Xiangxi River,the mountainous hills and soil conservation zone of the Three Gorges reservoir area,the mountainous hills and soil conservation zone of Juzhang River,the mountainous water conservation and soil conservation zone of Qingjiang River,and the human settlement environment maintenance zone of central city.Such six sub-zones involves five basic functions of soil and water conservation:farmland protection,ecological maintenance,soil conservation,water conservation,and human settlements environment maintenance.In conclusion,the division of water and soil conservation zones in prefecture-level cities should follow national and provincial water and soil conservation zoning on one hand,and meanwhile highlight local characteristics and adapt to local conditions on the other.The soil erosion control work in Yichang City should put prevention first,protect water sources,and strengthen the supervision focuses of soil and water conservation.