فصلنامه اقتصاد کشاورزی
سال دوم شماره 4 (زمستان 1387)

Economic returns to investment in agricultural research, education and extension were evaluated by relating total factor productivity and research, extension and education expenditures. The impact of research and extension induced technological change were also estimated by a rightward shift in the supply function of improved variety of wheat. The findings showed that research and education variables have positive effects on total factor productivity, while the effect of extension on agricultural productivity was not significant during the period considered. The distribution of economic gains between consumers and producers depends on the proportional shift of the supply function, rate of technology adoption, proportion of the crop marketed, and elasticity of demand and supply for the crop. Consumers and producers economic gains from advances in extension and research in the wheat production of Iran may be used as a basis for determining a national taxing schedule.

In this study environmental and farmer's objectives of Marvdasht district growers were considered jointly using multi objective programming. Different amounts were chosen for each objective and several plans were developed. Based on the results, it was revealed that, there was a trade off among objectives and a better combination of objectives is available, compare to current plan. It was also found that some patterns may be able to improve environmental objectives. Barley and tomato were recognized pioneer crops in that they may provide desirable combination of objectives, followed by wheat and rice.

The purpose of this study is determining the economic efficiency of agricultural production cooperatives and factors affecting it and their profits. The data were collected using multiple random sampling methods. The estimation results of profit function in Fasa, Firouzabad, Marvdasht and Eghleed cooperatives showed that amount of primary and existing capital and cost of total activities of agricultural production cooperatives have direct relationships with their corresponding frontier profit. As the results of economical efficiency distribution of these agricultural production cooperatives showed that average of economical efficiency score is 0.71 with a relatively high range (between efficient and inefficient of agricultural production cooperatives). Therefore there is a possibility to raise their profits through transferring managerial factors of high efficiency agricultural production cooperatives to those with low efficiency. As the results showed that managing director level of education, number of activities of agricultural production cooperatives (activities diversity), distance of agricultural production cooperatives from downtown and agricultural production cooperatives located in Firouzabad relative to other mentioned agricultural production cooperatives had direct relationship with economical efficiency of agricultural production cooperatives and the kind of governmental management of agricultural production cooperatives relative to independent management and activity period of agricultural production cooperatives and the agricultural production cooperative located in Fasa city relative to Eghleed and Marvdasht and the agricultural production cooperatives located in Eghleed city relative to Marvdasht city had indirect relationship with economical efficiency of agricultural production cooperatives in Fars province.

Amir-kabir dam is one of the main sources of Tehran residential water use. Also, it used for irrigation, generating hydropower electricity and controlling flood. In this study, after forecasting Karaj river flow by Monte-Carlo simulation, the dam water allocation between agricultural and urban sector is considered by lexicographic and weighted goal programming. Results of lexicographic model showed that, regarding to decision maker objectives, domestic water use and gross margin of agricultural sector could be increased. In weighted goal programming, more water was allocated to domestic water and gross margin of agricultural sector and hydropower electricity were more than the goals. In addition, according to established model, it is possible to consider various goals and situations from standpoint of water management of the dam.

Optimal using of soil and water resources leads to their conservation and farmer's income growth. This study aims to determine the optimal cropping pattern in the farms of east rural region of Isfahan. Several goals such as maximizing cultivated area, net returns, employment, and also conservation and sustainability of the water resources were considered simultaneously. After gathering of needed data from several resources and interviewing with experts and processing them, a mathematical model was formulated by using multi criteria goal programming (GP) technique and solved by LINDO software for the study area. Based on the results, rice, sugar beet and alfalfa were eliminated from the cropping pattern and the cultivated areas of potatoes and corn were increased. Wheat, barley and silage maize have had almost the same area in both existing and optimum cropping patterns and the area of onion has been reduced. In addition, there was an increase in net returns by26.2 and 38.2 percent, employment by 15.1 and 2.2 percent and also decreasing of water consumption by 10.7 and 9.7 percent respectively in the north and south Baraan rural regions. Therefore, advising farmers to adopt such techniques could be beneficial to them and the region.