فهرست مطالب rohallah fatahi nafchi

In this paper, the effect of inter-basin water transfer on the economic value of water resources has been investigated through a case-study of the Kamal Saleh dam from the Sarband Basin to the central Arak Basin. For this purpose, by using the mathematical model developed in this research, the economic value of agricultural water was investigated without regard to transferred water resources and considering its impact for wheat, barley, alfalfa and corn. The input data for this study was included meteorological and agricultural information, volume of consumed water, wastewater volume, volume of water transfer from Kamal Saleh Dam, as well as information about costs and incomes of the crop year 2015-2016. The results showed that water transfer to Arak city would increase the economic value of agricultural water resources in this city. So, the economic value of water estimated from three methods including weighing the area under cultivation, the volume of water consumption and product income for increasing crop area of corn were increased 10, 7.5 and 9 percentage, respectively . In addition, by increasing crop area of alfalfa the economic value of water estimated from all three methods was increased 2%. Increasing the economic value of water resources can be one of the solutions to sustainable development and food security. However, inter-basin water transfer projects should be implemented with all technical and economic and environmental factors, with emphasis on social and political considerations.

The existence of 35 to 45 million hectares of desert areas in Iran and many restrictions such as lack of precipitation, have caused many challenges for the development of these areas. On the other hand, improper utilization of existing resources has resulted in desertification as a natural phenomenon, which is increasing annually. The activities that have been tracked down desertification decades ago have only managed to control a very small corner (about 9.1 million hectares) of these areas. Desertification is the consequence of two challenges of climate change and freshwater scarcity. In Iran, 43.7 million hectares are desert ecosystems in the wilderness of the country, of which about 20 million hectares of desert ecosystems are affected by wind erosion. Meanwhile, 4.6 million hectares in 183 districts in 82 counties and 18 provinces of the country are considered critical wind erosion centers. In general, natural and human factors are among the main origins of desertification. In arid and semi-arid areas due to lack of precipitation, water is the most important limiting factor for plant deployment. Due to the quantitative and qualitative limitations of water resources, the survival of plants in desert areas, mainly depends on the choosing appropriate irrigation method. The purpose of this study was to compare Water Box method, which is a particular form of irrigation, with surface and drip irrigations for planting hawthorn plant, which is often used for desertification projects in semi-arid areas such as Iran. Experiments were carried out in the research field at Shahrekord University in the coordinate 32.3526° N, 50.8261° E and 2105 meters above sea level. The study area is 7 km far from the Shahrekord synoptic meteorological station. Shahrekord climate is categorized as Dcas climate by Copenhagen division method, which is characterized by moderate cold weather conditions with warm summers. In surface and drip irrigation methods, five irrigation regimes with zero, 25, 50, 75 and 90 percent of water requirements each with three replications were applied. In the Water box method, due to the self-regulation of the system and the no possibility of deficit irrigation, experiments with 15 similar replications were performed. Plant parameters such as stem diameter, height, seedling survival percentage and water content in each treatment were measured by one-month interval and compared to each other at the end of the study. The results of this study showed that the Water Box system, while significantly reducing the amount of consumed water (92% than drip irrigation) and high survival rate of seedlings (in this research 100%), is a useful method for establishing some hawthorn seedlings for combat and control of the desertification phenomenon. The highest growth was observed in irrigation treatments with 25 percent low irrigation with 60 cm height growth. Also, the lowest growth is due to irrigation with 90 percent low irrigation. In order to compare the mean annual growth rate of treatments, data were analyzed in SPSS software using the Duncan test at a significant level of 5 percent. The highest water use efficiency was related to water Box irrigation with 2.5 cc/l, which was obtained with a relatively large distance from other treatments, while, as mentioned in the previous sections, the water consumption of this treatment 92 percent low irrigation than full drip irrigation. The lowest water use efficiency was related to irrigation with 75% irrigation, which was 0.15 m3 l-1. In total drip irrigation treatment, water use efficiency was estimated to be 0.16 cm/liter, which shows that although the growth of this treatment was in good condition, it has poor results regarding water use efficiency. Due to the resistance of hawthorn to drought, only three of the cultivated seedlings were dried. The percentage of viability in the Water Box method was 100 percent. However, the difference in the percentage of vitality according to Duncan's method was not significant at 5 percent level. The results of seedling survival percentage were consistent with Naseri et al.(2005). They did not observe the significant difference between irrigation treatments in terms of viability. Due to the lack of research on irrigation with the Water box system, it is recommended that other researches be carried out on the use of this system for irrigation of other (productive) species. The location of the installation and tiling of wicks is one of the things that need to be addressed in the future research.

Agriculture development and improvement of soil and water resources productivity mainly depends on irrigation efficiency and reduction of water losses. This research was conducted in Borougen, Khanmirza and Shahrekord plain during 2010 growing season in order to evaluate the furrow irrigation systems. Evaluation of furrow irrigation systems were carried out in Potato fields in Borujen and maize fields in Khanmirza and Shahrekord plains. According to the results, application, conveyance, adequacy and overall irrigation efficiencies of Borujen plain were calculated 49.27, 83.65, 98.22 and 41.53 in percent, respectively. Such values for Khanmirza plain were 55.41, 77.11, 60.2 and 41.58 percent and those of Shahrekord plain were, 61.41, 88.43, 84.24, 54.67 percent, respectively. The results show that the application and adequacy efficiencies of furrow irrigation systems in these plains are acceptable. The overall irrigation efficiency was low mainly due to conveyance efficiency. Lining the transmission canals, using the standard structures and using of gated pipes, instead of traditional methods especially in furrow irrigation, is recommended and can be useful for improving distribution efficiency on farm.