Integrated assessment of ecological land capability and land suitability for irrigated agriculture in Alborz Province Iran.

Increasing population density and improper land use have led to significant degradation of land resources, which is now a major environmental problem. A key challenge in sustainable agricultural planning is the separate application of land capability assessment (LCA) and land suitability assessment (LSE) methods in land spatial planning. The main objective of agricultural land suitability assessment is to assess the potential and constraints of land relative to the needs of target crops. This study aimed to develop a practical approach to integrate ecological LCA models with LSE models in Alborz province, Iran. Four cereal crops with a history of irrigated cultivation in the province were selected as target crops. The LCA model was integrated with the LSE model using nine factor-type and eight constraint-type criteria. The findings showed that approximately 7% of the province is suitable for irrigated cultivation of four crops, while the current irrigated agricultural area is approximately over 11%. A comparative analysis of two multi-criteria decision-making (MCDM) methods showed that calculating the programmable water amount and replacing monthly temperatures with continuity for target crops instead of the annual mean temperature by reflecting the potential agricultural capacity of the land and the initial crop composition increases the accuracy of the suitability measurement, which reduces the land identified as suitable for irrigated agriculture.