Ecological risk assessment of wetland ecosystems using Multi Criteria Decision Making and Geographic Information System

Nowadays, wetlands are at risk from a wide range of stress factors. Practical application of wetland ecological risk assessment will result in a better understanding of how physical, chemical, and biological stressors impinge on wetlands and will provide a framework for prudent wetland management. An important aspect of wetland management is to identify ecological risks affecting the area and to develop a wetland-zoning map based on those risks. This study uses a process of ecological risk assessment (ERA) to identify stress factors and responses within the framework of an ecosystem-based approach. All potential environmental factors, physical, chemical and biological need to be examined in context. This study aims to present a systematic methodology for risk assessment and zoning of wetland ecosystems. Initially, the most important risks threatening wetlands are identified in an ecosystem-based approach. Endpoint assessments are defined according to values and functions of the wetland and the ecological risks associated with these endpoints are identified. In the characteristics step, risks are analyzed according to severity, probability and a range of consequences. A Multi Criteria Decision Making (MCDM) method is used to prioritize these risks on the basis of experts' opinions. Geographic Information System (GIS) is used to develop a zoning map with a combination of risk layers according to importance. Finally, management strategies are proposed to deal with the risks. The proposed methodology was applied to Shadegan International Wetland, located in southwestern Iran. This wetland is in the Montero list and is currently threatened by various risks. According to the results, high-ranking potential risks and areas with different levels of risk and management strategies were proposed for this wetland. (C) 2014 Elsevier Ltd. All rights reserved.