湿地脆弱性评价研究进展

湿地脆弱性评价是近年来湿地科学及可持续性科学领域的热点和前沿.湿地脆弱性评价研究经历了从湿地脆弱性特征定性评价,到湿地脆弱性定量评价,再到气候变化下湿地脆弱性评价的发展历程.首先,在对湿地脆弱性概念归纳总结的基础上,提出湿地脆弱性是在自然环境和人为压力下湿地退化的程度和可能性.其次,定性介绍了水土流失、水热分配不均、湿地退化等主要脆弱性特征表现;并以脆弱性评价的基本步骤为主线论述了模型法、特征法、综合指数法、EFI评价法、空间分析法等主要研究方法;同时,从不同角度概述了气候变化背景下的湿地脆弱性,总结了湿地水文景观分类法、生物完整性指标法、模型法、空间分析等评价方法.最后,指出湿地脆弱性研究中存在的概念不统一、评价标准不一致、评价指标范围较狭窄、动态研究偏少、定量评价的不确定性等主要问题,提出了完善评价体系、加强动态研究和国内对气候变化下湿地脆弱性的定量研究以及不确定性分析、脆弱性评价与决策管理衔接等湿地脆弱性未来研究的重点.

A Review on the Studies of Wetland Vulnerability Assessment

The assessment of wetland vulnerability is a critical issue and a frontier in the research area of wetland science and sustainability science.It has developed greatly in content and methods of assessment from vulnerability characteristics of qualitative evaluation to comprehensive quantitative evaluation to climate change special vulnerability evaluation.Firstly,the different definitions of wetland vulnerability from literature were analyzed,and the convergences and divergences among these definitions were illustrated in the paper;based on this,discussed the own meaning of the term.Secondly,it introduced the main characteristics of wetland vulnerability that contains water in short supply,short of water resources,water pollution,disasters of flood and drought,artificial unreasonable activities,degradation of wetland and so on.Then,it reviewed the main content and methods of assessment in different phases based on the wetland comprehensive quantitative evaluation.The approach of vulnerability assessment generally is as follows:constructing assessment index system,selecting assessment unit,determining assessment method and graduating vulnerability classification.The methods of constructing assessment index system include modeling vulnerability,characterizing vulnerability,and identifying a single representative index of vulnerability.The assessment units can be surface-based vector unit or point-based grid unit,or their combination.The assessment models include mathematical models,network models and space models.Mathematical models,such as comprehensive index method,analytic hierarchy process,method of ecological frangibility index,method of fuzzy comprehensive evaluation,are currently the most popular,but space models have more potential.The vulnerability of wetlands classifies the content into 5 aspects:vulnerability based on hydrologic landscape,vulnerability of location of wetland,vulnerability based on changes in structure and function of wetland ecosystem,vulnerability of wetland bio-community and vulnerability of specific types of wetlands with hydrologic landscape,structure and function of wetland ecosystem and spatial angle.There are 4 main methods to assess vulnerability of wetlands to climate change:hydrologic landscape,biological integrity,models and spatial analysis.Finally,the paper has a discussion of the problems in the field of wetland vulnerability,such as unified definitions and scientific terms,inconsistent evaluation standards,narrow evaluation indicators,less dynamic researches,uncertainty of quantitative evaluation.And it points out that more emphasis should be put on studying vulnerability conceptualization,dynamic vulnerability,quantitative evaluation of wetland vulnerability to climate change in China,uncertainty analysis and comparison of managing vulnerability.