Investigating landuse schema in north-easteran iranian provinces.

The type of land use and its management are one of the most important factors in producing surface runoff, soil erosion and sediment yield in watershed areas. Due to inattension to these problems, the amount of surface runoff, soil erosion and sediment yield have no good signs. On the other hand, no observing land suitability causes high production costs and reducing the net income in these areas. In this project, that was executed in national scale and in two north-eastern provinces of Khorasan Razavi and Semnan, different land managements, as well as their net incomes and the amount of soil erosion and sediment yield of each land use were computed and used as input data in a multiobjective linear programming model achieve the least soil erosion and the highest net income. The results would be an introduction for introducing an optimized land use and available resources schema in the country. For this purpose a linear programming model was used in three different scenarios including current land use condition without land management (senario 1), current land use condition with land management (senario 2) and standardized land use condition (senario 3). The results of this study showed that the present land uses are not at the optimum level to minimized soil erosion and maximized income and it should be changed at the optimum condition. In Khorasan Razavi province and in optimum condition, the area of orchard should be increased by 10.44 percent, while the area of drylands and irrigated lands should be decreased by 0.27 and 15 percent, respectively. Also, the amount of soil erosion and annual net income after optimization and in standard management of landuse decreased by 46.6 percent and increased by 0.22 percent, respectively. In Semnan province and in optimum condition, the area of orchard, ranges and irrigated lands should be increased by 28.85, 74.12 and 283.78 percent, respectively. Also, results showed that the amount of soil erosion and annual net income after optimization and in standard management of landuse decreased by 16.28 percent and increased by 94.58 percent, respectively. Key words: Land management, Land use, Linear programming, Optimization, Sensitivity analysis