عنوان مقاله [English]
The purposes of this study were to determine the value of marginal product of irrigation water, to determine the cost of irrigation water, to estimate cost of production per hectare for different groups, to determine the price elasticity of water demand and determine the water price by Gardner method. This study is carried out in Ghazvin plain in 1995.The irrigation area under Taleghan dam was divided into five homogenous regions, on the basis of the providing cost for water and the length of the water canal. Then, the required data were obtained from 127 farmers who were selected from 24 villages of Ghazvin plain by sampling method. In this study, water demand function, the values of marginal production were estimated by linear programming, Econometric and engineering economic methods. Results showed that: Price elasticity was less than one and demand for water relative to its price tends to be inelastic. The value of marginal production of water was more than the price received by authorities. Average price of irrigation water is estimated about 65 rials per (m3) by Gardner method. The value of marginal product of water for farmers groups (10 ha) was 208, 113, 77, 69 and 120 rials, respectively.