辽河流域水生态分区研究

依据河流生态学中的格局与尺度理论,对流域水生态分区的内涵进行辨析,从理论上对区划方法进行了研究.通过对辽河流域自然要素及水生态特征的分析,建立了辽河流域水生态分区体系.明确了各级分区的主要内容与分区依据,提出了各级分区的特征指标,从而建立了流域水生态分区的指标与方法体系.结果表明,辽河流域包括2级水生态区,一级区可根据流域水资源空间特征差异进行划分,其目的是反映大尺度水文格局对水生态统的影响规律,二级区是根据地貌、植被、土壤和土地利用等自然要素进行划分,目的是反映流域尺度的地形、地貌及植被对河流栖息地环境特征的影响.在GIS技术支持下,采用多指标叠加分析和专家判断方法,将辽河流域划分为3个一级区、14个二级区,对不同分区的水生态系统特征及其所面临的生态环境问题进行了总结.对水生态分区在流域管理中的应用进行研究,提出了基于水生态区的环境管理技术支撑体系.

Study of aquatic ecoregion in Liao River Basin

Based on the channel geomorphology and hierarchy-scale theories of river ecology, the conception of aquatic ecoregion is discussed and method to delineation of ecoregion is studied theoretically. Through analyzing natural elements and aquatic ecological characteristics of the Liao River Basin, the dividing system of aquatic ecoregion in the Liao Basin has been established. The major content and criteria using in classification are identified and characteristics indicators for different ecoregion have been proposed. Thus indicator system and methodology of delineation of watershed has been established. The results indicate that the aquatic ecoregion of Liao River Basin includes two grades. The grade I is divided based on the spatial diversity of water resources in the basin. The purpose is to reflect the influence of large scale hydrological pattern on aquatic ecosystem. Grade II is delineated based on natural elements such as geomorphology, vegetation, soil as well as land use. The purpose is to reflect the influence of the topographic and geomorphology on the environmental characteristics of river habitats. Finally Liao River basin is divided into 3 Grade I regions and 14 Grade II regions by methods of multi-indicators overlay analysis and expert judgment with support of GIS technology. The ecological characteristics and environmental problems confronting in each region are summarized. The application of ecological region in river basin management is studied. A technology support system basis of aquatic ecoregion for environmental management is proposed.