Document Type: Research Paper
Watershed Department, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
This research has concentrated on the physical and socio-economic impacts of vegetation-based management scenarios targeting on flooding and soil erosion issues in the Ramian watersheds. The Ramian watershed with an approximate area of 24000 ha is located in Golestan, Iran. For each sub-watershed, four biological actions (activities) and 16 management scenarios have been considered. Physical impacts were studied using the SCS (Soil Conservation Service) hydrologic model and the EPM (Erosion Potential Method) model. Economic and social impacts have been evaluated using the cost/benefit analysis and the examination of the results of a social survey, respectively. Some physical, social, and economic indices were chosen and quantified. The indices then were standardised using the interval standardisation technique. Best scenarios were determined using a Multiple-Criteria Decision Making (MCDM) technique. To weight the indices, four perspectives were used. For the first three perspectives one of the physical, social and economic criteria were assigned higher weights while for the fourth perspective all criteria were given equal weights. Trade-off analysis of the results indicates that for most sub-watersheds more than one single management solution can be recommended on the basis of the different perspectives. The results showed that the multiple-criteria decision making serves as a valuable tool to represent the watershed system as a whole, to incorporate output from models and expert-judgments to examine the trade-offs among outcomes necessary to decision making.