The Analysis and Ranking of Spatial Distribution of Waste Landfill Potential, Using AHP Model and TOPSIS Technique (Case Study: Rasht)

Abstract

One of the effects of a gradual population increase in the urban areas is waste in crescent and its disposal. Among the common methods of waste management, land filling is technically, ecologically and economically important. The purpose of this study is to determine the appropriate spatial potential for sanitary landfill of waste in Rasht, based on location criteria and using GIS and remote sensing. Zoning of suitable burial sites was done based on the 4 main criteria of land use, hydrological characteristics, geological characteristics and accessibility. In a current study, SRTM sensor data, which is paired with a short time interval (to reduce changes occurring at ground level) was used to prepare a digital model of land. The maps derived from the digital model of land, included elevation and slope maps that were used to prepare the criteria of the "geological profile." After standardization and preparation of maps, in order to achieve the weight and importance of each layer to find suitable landfills, the weight of the layers used was calculated by hierarchical analysis method. Considering the effective factors in locating the municipal waste landfill and weighing each of the criteria and sub-criteria, five values of very suitable, suitable, relatively suitable, inappropriate and very inappropriate were specified. To determine the priority of the very suitable areas, the TOPSIS method was used. Among the 9 sites introduced to the TOPSIS algorithm, site four, with an area of ​​89.36 hectare, which is located in the southern parts of Rasht, was determined as the most suitable place for waste disposal.