Economic Analysis of the Effects of Climate Change Induced by Greenhouse Gas Emissions on Agricultural Productions and Available Water Resources (Case Study: Down Lands of the Taleghan Dam)

Introduction: Greenhouse gases absorb the radiation reflected from the earth surface which would otherwise be sent back into space. The composition and mixture of these gases make life on earth possible. In recent years, human activity has affected both the composition and mixture of the atmosphere, modifying the climate. When climate changes, crop production is affected. There are many studies that consider the type and amount of production changes for particular crops, places and scenarios. Others attempt to expand knowledge about production changes and their impacts on economy and regional welfare. Climate change affects agriculture through direct and indirect affects i.e. temperature, and precipitation changes in the biological and physical environment. Restriction in water availability is one of the most dramatic consequences of climate change for the agricultural sector. Water availability is expected to be even more limited in the future. Scarcity of water is due to potential evapotranspiration increase. It is related to increase in air and earth surface temperatures. This phenomenon is important in low-precipitation seasons, and is even more severe in dry areas. The number of regions with loss of soil moisture is expected to increase, resulting in direct economic consequences on the production capacity. Considering the above decisions, the main objective of this paper is to integrate climate change into agricultural decision-making by using an Economic Modeling System to identify the impacts of climate change induced by greenhouse gas emissions on agricultural sector productions and available water resources in the down lands of the Taleghan Dam. Materials and Methods: In this study, the effects of greenhouse gases on climate variables of temperature and precipitation under emission scenarios A1B, A2 and B1 were evaluated using time series data from 1981- 2008 and General Circulation Models (GCM). Then Ordinary Least Squares (OLS) was used to survey the impacts of climate variables on the selected products yield. Changes in agricultural production, farmer’s gross profit and economic value of irrigation water were analyzed and compared with the base year by the regression analysis results in the Positive Mathematical Programming (PMP) model. This methodology that was developed by Howitt (1995) to calibrate agricultural supply models has been used to link biophysical and economic information in an integrated biophysical and economic modeling framework and to assess the impacts of agricultural policies and scenarios. These models are also accepted for analyzing the impact of climate change and water resources management policies and scenarios. The PMP model used in this paper is a three-step procedure in which a non-linear cost function is calibrated to observe values of inputs usage in agricultural production. In the basic formulation, the first step is a linear program providing marginal values that are used in the second step to estimate the parameters for a non-linear cost function and a production function. In the third step, the calibrated production and cost functions are used in a non-linear optimization program. The solution to this non-linear program calibrates to observed values of production inputs and output. The required data in this paper were collected from meteorological stations and the relevant agencies in the Qazvin province. Regression functions estimated in Eviews software package and the PMP model were solved in GAMS (General Algebraic Modeling System) software. Results and Discussion: The results obtained in this paper showed that with emissions of greenhouse gases under the studied scenarios (A1B, A2 and B1), the average annual climate variables of temperature and precipitation changes from 1.64 to 2.28 °C and from20.92 to 1.1 mm, respectively. With these change, the yield of the most selected products decreases in the down lands of Taleghan Dam. Moreover, the obtained results showed that with emissions of greenhouse gases under the scenarios A1B, A2 and B1, the total acreage of the selected products changes from 2.18 to 4.09 percent. Total used water also decreases from 1.67 to 5.18 percent. Moreover, with emissions of greenhouse gas under the above scenarios total farmer’s gross profit decreases from 1.93 to 3.72 percent. However, the economic value of water increases from 4.27 to 13.6 percent in comparison with the base year. Conclusion: In this study finally, in order to reduce greenhouse gas emissions in the vicinity of the down lands of the Taleghan Dam, it is recommended that the government should use punitive tools (green complications) for polluting units and serve the private sectors in forestry projects in the vicinity of the industrial towns. Keywords: Agricultural productions, Climate change, Greenhouse Gases, Positive Mathematical Programming, Taleghan Da

Assessment the Economic Damage of Inter-Basin Water Transfer on Cropping Pattern and Farmers’ Income Situation in the Origin Basin (Case Study: Water Transfer of Alamoutrood to Qazvin Plain)

Introduction: Sustainable management of water resources is one of the most important disturbances of current century and many scientists and investigators have already started to pay attention to it from last decade and early 21st century. Iran is in the semi-arid region and thus disproportionate distribution of water resources, so atmospheric precipitation and soil in the country, along with factors such as climate change, drought, environmental protection, ecological special situation, maintain the current pattern of population distribution provides various challenges. Industry and agriculture sectors create a regional balance tailored to the development needs on the one hand and focusing on distribution balanced and optimal management of water resources on the other hand. Transfer of water between river basins (watersheds, catchments), which is basically a hydrological category, different from the notion of transferring water over political boundaries, usually called transboundary water transfer. Interbasin water transfer usually implies large hydraulic engineering structures, conduits, canals, dams, pumping stations, and consequently shares the mistrust which meets large scale infrastructural solutions in water management, often criticized and opposed with the argument that one should first try to reduce water wastage, before embarking into costly investments. Inter-basin water transfer in fact is physical transfer of water from one basin to another basin. This transfer (Inter-basin water transfer) despite the elimination of shortcomings in the transmission destination areas, can the source of many changes in the cropping pattern, and farmers gross profit. Natural environment, migration, reduction of dependency to agriculture, small industries in the origin basins all requires assessments before the implementation of the water transfer projects. In Iran also water transfer from regions with high rainfall to arid regions has been performed by building the dam, canals, streams and aqueducts. Even today, many projects are implemented in Iran that water transfer project of Alamoutrood to Qazvin plain is one of the most important of these projects. According to reports of Regional Water Company of Qazvin province and the specifications of inter-basin water transfer project of Alamoutrood to Qazvin plain will be out from the farmers availability of Alamut region about 370 million cubic meters of irrigation water. This issue has the huge impacts on cropping pattern and farmers economic and livelihood condition in the origin basin (Alamout region). Therefore, in this study a hydrological-economic modeling system to analysis the effects of water transfer project of Alamoutrood to Qazvin plain on cropping pattern, farmers gross profit and economic value of irrigation water in the Alamut region (origin basin) was used. Materials and Methods: Nowadays different methods to analysis of the issues related to the management of water resources and agriculture are used. One of the most important of these methods is mathematical programming that in recent years are in use to solve problems of water resource management sector and analysis of the agricultural policies. In this study a hydrological-economic modeling system consists of the Positive Mathematical Programming (PMP) and product function with Constant Elasticity of Substitution (CES) to analysis of the effects of inter-basin water transfer on land use, farmers income situation and economic value of irrigation water in the origin basin (Alamout region) was used. The first time PMP model developed by Howitt (1995) to calibrate agricultural supply models have been used to link biophysical and economic information in an integrated biophysical and economic modelling framework and to assess impacts of agricultural policies and scenarios. These models are also accepted for analysing the impact of water resources management policies and scenarios. PMP model used in this paper is a three-step procedure which in it a non-linear (Quadratic) cost function is calibrated to observed values of inputs applied in agricultural production. In the basic formulation, the first step is a linear program providing marginal values that are used in the second step to estimate the parameters for a non-linear cost function and a production function. In the third step, the calibrated production and cost functions are used in a non-linear optimisation program. The solution to this non-linear program calibrates to observed values of production inputs and output. The required data in this study are related to the cropping year of 2013-2014 of Qazvin province. Results and Discussion: The obtained results in this study showed that inter-basin water transfer of Alamoutrood to Qazvin plain resulted in using 10 to 40 percent the supply of irrigation water leads to reduction of cropping pattern from 1/71 to 5/52 percent in Eastern Alamut Rodbar and from 2/17 to 6/32 percent in Western Alamut Rodbar. The above restriction after inter-basin water transfer of Alamoutrood to Qazvin plain leads to reduction of farmers gross profit from 2/58 to 8/21 percent in Eastern Alamut Rodbar and from 3/18 to 9/82 percent in Western Alamut Rodbar. In addition, the results of this study showed that inter-basin water transfer of Alamoutrood to Qazvin plain affects the economic value of each cubic meter of irrigation water in the origin basin (Alamout region) and leads to increase it from 3/23 to 31/1 percent in Eastern Alamut Rodbar and from 4/09 to 14/0 percent in Western Alamut Rodbar. Moreover, the results of this study showed that farmers irrigation water demand function in Alamout region changes after inter-basin water transfer of Alamoutrood to Qazvin plain and farmers are compelled to buy every cubic meter of irrigation water at higher price compared to the current situation (before inter-basin transfer of water). Increasing of the rural people emigration, urbanization development, reducing tourism and disturbance in the ecosystem origin basin are the potential consequences of inter-basin water transfer of Alamoutrood to Qazvin plain. Conclusion: Implementation of Inter-basin water transfer projects is responsive to resolve the water shortage problems in destination basins in short-time periods and the situation in the long time will be repeated as before. Therefore, it is recommended that instead of inter-basin water transfer project from Alamoutrood to Qazvin plain (despite the high cost for implementation of project and creating the detrimental problems in the origin basin) other appropriate methods in the field of water resources management (such as equipping of lands to modern irrigation systems, use of deficit irrigation techniques, modification of cropping pattern by products with low water requirement, increase the irrigation efficiency by repairing and equipping of water transfer channels) to solve the problem of water shortage in the destination basin (Qazvin plain) to be used. The results of this study showed that inter-basin water transfer of Alamoutrood to Qazvin plain leads to reduction of cropping pattern and farmers’ gross profit. Therefore implementation of this project by considering of economic, social and environmental considerations in the origin basin (Alamout region) was recommended