کاربرد مدل برنامهریزی خطی فازی چند هدفه دو مرحلهای جهت تدوین الگوی بهینه کشت (مطالعهی موردی بخش مرکزی شهرستان مشهد)

Abstract

Optimal allocation of water resources is an essential service in agriculture that must be considered by farmers. One of the most significant factors in optimal allocation of water resources in agriculture is to define optimal farm cropping pattern. In this study, in order to determine optimal cropping pattern and water resources allocation in central district of Mashhad city (Toos village), the two-stages multi-objective fuzzy linear programming was used. The required data was collected through interviews with farmers of the study area and filling in 116 questionnaire using simple random sampling during the years 2012-2013.The results indicated that, optimal values in the two-stage multi-objective fuzzy linear programming model for maximizing gross margin is 239420100 Rials, for utilizing organic fertilizers is 3867.19 Kg, and for minimizing the consumption of irrigation water is 53645.62 square meters, which were modified in the second phase. The objective amount of chemical fertilizer was 817.80 kg., having no change in the second phase. The cropping pattern will be optimized, if the most area under cultivation being allocated to potato, then to barley, wheat, t, onion and sugar beet, while tomato and corn cultivation being removed. Results illustrate that, two-stage multi-objective fuzzy linear programming model in comparison with multi-objective fuzzy linear model yield better results in defining optimal cropping pattern and allocation of irrigation water to the study area.