Development of a model using matter element, AHP and GIS techniques to assess the suitability of land for agriculture

Land suitability assessment is an essential step for land use planning and development. Over the last decade, many researchers, organizations, research institutes and governments have tried to provide a comprehensive procedure for the optimal use of agricultural land, but have failed to balance competing issues in a systematic way. Matter element is a multiple criteria decision analysis (MCDA) technique which has shown high potential for solving complicated issues. The use of MCDA techniques such as matter element and analytic hierarchy process (AHP) based on remote sensing (RS) and GIS is a flexible and effective framework to assess and map several different criteria for the strategic placement of cropping. We used data from 167 soil profiles covering 12,000 ha of land located in Ardabil province, northwest of Iran to assess criteria using MCDA techniques that may limit barley production under irrigation. After soil sampling and analysis, 24 soil series (all Aridisols) and 66 land units were identified and separated in the study area. Several criteria were limiting, but the most limiting criteria included: soil depth, slope, climate characteristics, pH, electrical conductivity, exchangeable sodium percentage, calcium carbonate equivalent and gypsum content. Combining and analyzing criteria in an AHP-matter element model generated a land suitability map for barley production. The coefficient of determination (R-2) between land suitability index and observed barley yield was 0.947 for AHP-matter element hybrid model. Modeled estimates were compared and showed that the hybrid approach of AHP and matter element techniques was more accurate than the storie and square root methods in selecting the most suitable areas for barley production. The AHP-matter element hybrid method can therefore improve planning and decision making regarding land which is suitable for barley cultivation. This approach may also be suitable other crops.