Assessment of urban river habitats: application and methodology
城市河流栖息地评价方法与应用

A healthy habitat is essential for maintaining biological integrity.Assessment of urban river habitats(URH) provides a scientific basis for their restoration and management,and the criteria for assessment are closely related to the characteristics of URH.Based on the idea and the radiant quality of Matter-element,as well as former research,an index system for assessment of URH including water quality,morphology,hydrodynamics and aquatic biology,was set up to meet the objective of river restoration.Besides the combining hierarchy process method,multilevel extension assessment is discussed for assessment of URH,and the extension method for diagnosis is introduced.The above theory and method were applied to a case study of the Ancient Canal in Zhenjiang city,and homologous indicator criteria were established linking restoration objectives and the actual condition of the Ancient Canal.After conducting field surveys for more than a year,6 representative reaches were selected for assessment,and the results indicate that the general habitat quality,water quality,hydrodynamics and aquatic biology are in poor condition.Further diagnosis indicated the water quality and hydrodynamics are the main factors that affect habitat quality,and water quality,water transparency,guarantee rate of water demand and longitudinal connectivity are the key indexes.Finally,some suggestions for habitat restoration of the Ancient Canal are provided based on above results.