湿地水环境可持续性度量指标体系的构建研究

Establishment of Index System of Sustainability Measurement on Wetland Water Environment

湿地水环境可持续性度量指标体系分为层次结构和组成结构。构建湿地水环境可持续性度量指标体系应遵循科学性、可操作性、简明性与完备性相统一、针对性与时空性相统一的原则。湿地系统的结构特征制约着湿地水环境可持续性度量指标体系的准则层,不同类型的湿地水环境,选择的度量因子及相同因子在度量中所占的权重不同,同类湿地水环境的可持续性应该有一套可以借鉴的度量指标和方法。在确定湿地水环境可持续性度量主要指标和权重的过程中,灰关联分析法、特尔斐法和层次分析法是可以采用的有效方法。

Wetlands, located at transitional zone of water area and land, provide important ecological, economic, and social benefits such as improving water quality, controlling flood, reducing nutrient pollution and habitat for a diversity of plants and animals and recreational opportunities. Furthermore, wetlands are also the ecologically sensitive and adaptive systems. However, many wetlands in China have been destroyed or degraded due to unsustainable use patterns. Water is the precondition of wetlands formation, and the dependence of wetlands on it polarizes the water sensitivity. Wetland water environment is the aggregation of factors which interact with water in the wetland ecosystem, and the sustainability measurement of wetlands water environment is to measure, judge and evaluate whether it is sustainable by establishing index system of wetland water environment. Establishing the index system of sustainability measurement on wetland water environment and constructing corresponding mathematic model are prerequisite to measure, judge and evaluate its sustainability level. Index system of sustainability measurement on wetland water environment, established following the principie of unification of science, maneuverability, conciseness, and maturity and unification of pertinence and space - time variance, is composed of hierarchy and composition structure. Hierarchy includes 4 levels： factors, principles, controls, and aims. First, the main indexes should be determined, using correlation analyses and Grey relevant analyses. In this paper, the principle level is wetlands structure, climate, biology, and water quantity and water quality. Then the weights of the indexes should be computed. There are many methods to calculate weights; Analytic Hierarchy Process （AHP） method and Delphi method are paied more attention to. The AHP is a mathematical method for analyzing complex decisions. It is a general theory of ratio scale measurement based on mathematical and psychological foundations. What it does is to aggregate the separate performance indicators into an integrated performance indicator. In the case of wetlands, the overall goal is to achieve sustainable management. Criteria are then defined by which each option should be considered in meeting the objectives. Each criterion can have sub - criteria. Many options can be constructed each containing different levels of criteria that contributes to the overall objective. The AHP facilitates a rigorous definition of priorities and preferences of decision makers. Decision makers may use Delphi method to do experiential judgment. Different types of wetland water environment have different measurement indexes and different weights of a same index; however, water environment of the same kind wetland should have a series of measurement indexes and methods used for reference. The of water environment sustainability measurement is explored. Howev- er, sustainability measurement on wetland water environment is not only a theoretic issue, but also a practical one. The principles to determine the main indexes and construction of the index system should be perfected in the actual practices.