Agroclimatological Zonation of Citrus in Lorestan Province with Index Overlay Logic and Fuzzy Logic

Climatic factors are the most important variables among effective factors in agricultural productions, which would cost too much to be controlled. So, the only possible way to stand against natural restrictions, especially climatic restrictions, is recognizing these restrictions, adjusting oneself to them and managing crops effectively. In this case study, climatic parameters of temperature, rain, day temperature, and environmental parameters like slope, slope direction, the distance from hydrograph network and soil are which are considered as important factors in the zonation of fertile lands for citrus in Lorestan province are investigated. In the present study, first the data of climatic parameters are collected; next the maps of the related parameters are done with various interpolation methods and the other methods in Arc GIS 9.2 software (Esri Company). These maps are then standardized with Index overlay logic and Fuzzy logic and criteria for planting citrus and each of them is given specific weight. Then, all of the standardized maps are integrated using AHP logic and subsequently, the appropriate locations for citrus orchards and zonation map in Lorestan province are identified. In the final map, by the Index Overlay logic, 981523/56 hectares of Lorestan lands are suitable for citrus plantation, 968921/14 hectares of Lorestan lands have a medium capability and 922175/22 hectares of Lorestan lands are unsuitable for this purpose. In the final map, by the Fuzzy logic, 1003218/231 hectares of Lorestan lands are suitable for citrus plantation, 1018497/982 hectares of Lorestan lands have a medium capability and 837386/428 hectares of Lorestan lands are unsuitable for this purpose. The final results show that the importance of each of the climate and land factors differs according to different phonologic stages in different regions of the province, and the possibility of recognizing the utility rates of citrus production would be provided through overlaying various effective layers of this yield in GIS environment.