Potential landfill site selection for solid waste disposal using GIS and multi-criteria decision analysis (MCDA)

Proper solid waste disposal is an important socioeconomic concern for all developing countries. Municipalities have their own policies, individual approaches and methods to manage the solid wastes. They consider wastelands outside the urban area as the best suitable for the solid waste disposal. Such improper site selection will create morphological changes that lead to environmental hazards in the urban and its surrounding areas. In this research, the site selection for urban solid waste disposal in the Coimbatore district used geographical information system (GIS) and multi-criteria decision analysis (MCDA). Thematic layers of lineament density, landuse/landcover, population density, groundwater depth, drainage density, slope, soil texture, geology and geomorphology were considered as primary criteria and weights for criteria, and sub-criteria were assigned by MCDA analysis. The resultant weight score was validated by consistency ratio so that the efficiency of the selected criteria was justified. The overlay analysis in GIS environment provides 17 potential zones in Coimbatore district, among which, four suitable sites were screened and refined with the help of field investigation and visual interpretation of satellite image. The result of landfill suitability map shows the effectiveness of the proposed method.摘要妥善处置固体废物是所有发展中国家的一个重要的社会经济问题。通常市政有自己的策略和方 法来管理固体废物,他们认为城市以外的荒地是最适合固体废物处置的地方,而不当的场地选择会造 成形态变化,危害城市及其周围地区的环境。本文采用地理信息系统(GIS)和多准则决策分析(MCDA) 技术对Coimbatore 地区城市固体废物进行选址。主要标准和权重包括线性密度、土地利用/土地覆盖、 人口密度、地下水埋深、河网密度、坡度、土壤质地、地质地貌,再采用MCDA 分析方法对各子标 准进行划分。通过一致性比验证所选标准的权重,从而证明所选标准的有效性。通过GIS 环境下的叠 加分析,选出Coimbatore 地区的17 个可能的区域,再通过野外调查和卫星图像的可视化筛选和细化 出4 个适宜的地点。填埋场适宜性地图验证了该方法的有效性。