Support system based on GIS and weighted sum method for drawing up of land suitability map for agriculture - Application to durum wheat cultivation in the region of Tiaret in Algeria

摘要

Due to the observed decreasing farmlands, it is important to identify the best lands useful for a sustainable agriculture (a productive and profitable agriculture that protects the environment and that is socially equitable). This identification is resulted in the development of land suitability maps for agriculture by combining several factors of various natures and of unequal importance. Spatial analysis approaches, based on the concepts of the weighted sum, combined with a Geographical Information System (GIS) offer the possibility to determine this type of maps. Indeed, GIS is a powerful tool for analyzing spatial data and establishing a process for decision support. The functions of the weighted sum shall make it possible to assign numerical weights, to distinguish between positive and negative criteria and to rank alternatives. A spatial decision support system has been developed for establishing the land suitability map for agriculture. It incorporates a version of the weighted sum method SAW (Simple Additive Weighting), applicable to the vector data model, in ArcGIS without leaving the GIS program package environment. This approach has been tested on Tiaret (Algeria) to assess the land suitability for the durum wheat agriculture. The parameters and the classification system used in this work are inspired from the FAO (Food and Agriculture Organization) approach dedicated to a sustainable agriculture. The coherence of results confirms the system effectiveness.