长江口生态系统特征和保护价值评价

Assessment of the ecosystem characteristics and conservation value of the Yangtze River Estuary

长江口是一个以咸淡水交互作用为基础的复杂生态系统,是东亚—澳大利西亚候鸟迁徙路线的重要节点,是中华鲟等珍稀水生动物生命过程中不可或缺的“三场一通道”。由于该区位于高度城市化区域,受人为干扰影响明显,生物多样性和生态服务功能下降等问题突出,迫切需要系统分析和评估该区域生态系统特征和保护价值,识别生态系统关键区,以实现保护与发展的空间统筹。通过识别和分析长江口生态系统特征,从国家代表性、生态重要性、保护基础三个层次构建保护价值综合评价体系,识别保护关键区。研究表明,长江口生态系统呈现“三高一低”的特征;滨海湿地生态系统、鸟类及水生生物多样性保护等方面均表现出显著的国家代表性,并且具备高敏感性、高风险、高生态服务功能特征。长江口保护价值呈现空间异质性,东部及水源保护区保护价值高,三级分汊航道保护价值较低,保护关键区集中在崇明东滩周边、北湖、九段沙、横沙西部及水库区。建议相关部门进一步推进长江口国家公园的规划建设工作,整合各类自然保护地,实现长江口生态完整性保护,促进长江大保护、长三角一体化的国家战略实现。

The Yangtze River Estuary is a complex ecosystem based on the interaction of salt and fresh water.It is an important node on the East Asian-Australasian Flyway for migratory birds and an indispensable"three sites and one corridor"for the life cycle of rare aquatic animals such as Chinese sturgeon.However,due to its location in a highly urbanized area,the region is significantly affected by human interference,resulting in prominent issues such as a decline in biodiversity and ecological service functions.There is an urgent need for systematic analysis and assessment of the ecosystem characteristics and conservation value of this region,as well as the identification of critical ecosystem areas,to achieve spatial integration of conservation and development.This study systematically identified and analyzed the ecosystem characteristics of the Yangtze River Estuary,and constructed a comprehensive evaluation system for conservation value from three levels:national representativeness,ecological importance,and conservation foundation.It systematically analyzed and evaluated the conservation value of the Yangtze River Estuary,and identified critical conservation areas.The results showed that the ecosystem of the Yangtze River Estuary exhibited the characteristics of‘three highs and one low’,indicating extremely high conservation value.Coastal wetland ecosystems,birds,and aquatic biodiversity conservation all demonstrated significant national representativeness,coupled with high sensitivity,high risk,and high ecological service function characteristics.The conservation value of the Yangtze River Estuary exhibited spatial heterogeneity.It was high in the eastern region and water source protection areas,but relatively low in the third-level branching channels.Critical protected areas were concentrated around Chongming Dongtan,Beihu,Jiuduansha,the western part of Hengsha,as well as reservoir areas.We suggest that relevant departments further advance the planning and construction of a national park in the Yangtze River Estuary,integrate various types of nature reserves,achieve ecological integrity protection in the Estuary,and promote the national strategies of comprehensive protection of the Yangtze River and integration of the Yangtze River Delta region.