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Aniseh Jami; Hamed Najafi Alamdarlo; Seyed Abolghasem Mortazavi
Abstract
Groundwater resources in the world are experiencing significant reductions due to climate change and drought. Therefore, in order to make appropriate decisions by managers and planners, forecasting and studying the economic effects of drought is essential. Thus, the purpose of this study was to ...
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Groundwater resources in the world are experiencing significant reductions due to climate change and drought. Therefore, in order to make appropriate decisions by managers and planners, forecasting and studying the economic effects of drought is essential. Thus, the purpose of this study was to investigate the welfare effects of drought on groundwater beneficiaries. Accordingly, the present study investigated the economic effects of drought and its impact on the cultivation pattern of the southern Mahyar Plain and changes in social welfare in the 2016-2017 crop years, using the groundwater market approach. For this purpose, three approaches of regression estimation, positive mathematical programming, and dynamic programming were used. The results showed that in drought conditions, the area under barley and wheat cultivation increased and the area under corn decreased. Other results showed that the reduction of water supply due to drought would reduce the social welfare by 1020 million Rials (based on 2016 prices). Therefore, it is suggested that the amount of welfare lost by farmers due to water shortages should be a criterion for determining the amount of compensatory payments.
Mehdi Akbari; Hamed Najafi Alamdarlo; seyed habibollah moosavi
Abstract
Climate change is one of the natural occurrences that cause temperature rise, reduced rainfalls, change in water balance, decline in production level, and frequent droughts. Therefore, predicting and evaluating the effects of climate change and drought could be very effective for future decision making. ...
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Climate change is one of the natural occurrences that cause temperature rise, reduced rainfalls, change in water balance, decline in production level, and frequent droughts. Therefore, predicting and evaluating the effects of climate change and drought could be very effective for future decision making. According to this approach, in this study, the effects of climate change and drought on cropping pattern and income risk effects in Qazvin plain were investigated. The LARS-WG model was used to simulate climate variables (temperature and precipitation) in the future, as well as their changes in the A1B, A2 and B1 climate scenarios. Also, the Standard Precipitation Index (SPI) was used to determine drought periods and water volume changes. Then, using the mathematical programming approach and compilation of the MOTAD-TARGET with PMP model, the cropping pattern was simulated in climate scenarios and drought periods and the risk effects of these scenarios were investigated. The results show that in all three climate scenarios, temperature increases and precipitation decreases, and cropping pattern changes toward crops with higher income stability. In drought scenario, due to reduced water volume, the cropping pattern tends to crops with less water requirements, and crops with higher income levels have less changes. Income risk, in the worst drought scenario (very severe drought) and climate change (scenario A2 during the period 2040-2049), would decrease by 68.1% and 6.377%, respectively. By reducing the income risk, the gross margin will be reduced. Considering the economic effects of climate change and drought in long-term, it is recommended to use drought and heat resistant varieties. Also, the area under cultivation of crops such as barley, corn, sugar beet, and tomato may be increased as they have a more stable income.
mehdi elahi; mohammad hasan vakilpoor; Hamed Najafi Alamdarlo
Abstract
Excessive withdrawal of groundwater resources in the agricultural sector has led to an increase in cultivated land area and agricultural production, however, it has led to dropping of groundwater levels and drainage of aquifers. Consequently, most of Iran's plains are now considered as forbidden plains ...
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Excessive withdrawal of groundwater resources in the agricultural sector has led to an increase in cultivated land area and agricultural production, however, it has led to dropping of groundwater levels and drainage of aquifers. Consequently, most of Iran's plains are now considered as forbidden plains for underground water extraction. Therefore, proper policies for management of groundwater resources are essential. For this purpose, the present study aimed to evaluate the effects of economic policies of the agricultural sector on management of ground water resources in Kabodarahang Plain, by using a Positive Mathematical Programming (PMP) and Maximum Entropy (ME). The data and information was collected by referring to the relevant organizations and completing 141 questionnaires with multi-stage cluster sampling by farmers in 2016. The results showed that application of various senarios such as price increases, groundwater allocation , and combination of quotation scenarios simultaneously with increasing prices (combined) at levels of 10%, 20%, and 30% cause reduction in cropped area, decreased net profit of farmers, and reduced water consumption. Also, the results showed that the groundwater price increases scenario was not much effective and only increased the farmers' expenses, but the allocation/quotation polices and the combined policy are recommended as effective policies. Another result revealed that the quotation scenario, compared to the other scenarios, has higher economic returns per cubic meter of water consumption, thus it has been introduced as the best scenario in this research. Finally, it is suggested that the cropping pattern be directed towards products such as wheat and potato that have more gross profit for the water consumed and thus have more economic returns.