Optimal irrigation water allocation using a genetic algorithm under various weather conditions

Growing water scarcity, due to growing populations and varying natural conditions, puts pressure on irrigation systems, which often are the main consumptive water users. Therefore, water resources management to improve the allocation of limited water supplies is essential. In this study, a non-linear programming optimization model with an integrated soil/water balance is developed to determine the optimal reservoir release policies and the optimal cropping pattern around Doroudzan Dam in the South-West of Iran. The proposed model was solved using a genetic algorithm (GA). Four weather conditions were identified by combining the probability levels of rainfall, evapotranspiration and inflow. Moreover, two irrigation strategies, full irrigation and deficit irrigation were modeled under each weather condition. The results indicate that for all weather conditions the total farm income and the total cropped area under deficit irrigation were larger than those under full irrigation. In addition, our results show that when the weather conditions and the availability of water changes the optimal area under corn and sugar beet decreases sharply. In contrast, the change in area cropped with wheat is small. It is concluded that the optimization approach has been successfully applied to Doroudzan Dam region. Thus, decision makers and water authorities can use it as an effective tool for such large and complex irrigation planning problems

Sustainable Management of Saravan Sylvan Park Using Stochastic Dynamic Programming

T he present study sustainable management of Guilan Saravan Sylvan Park was planned. The used method in the form of decision support model in three10-year period was studied for parks of various states and with considering the economic, ecological and social criteria during the years 2008 to 2038. By using hierarchical fuzzy analysis method, the reaching to an optimal level of economic, ecological and social simultaneously and as their combined utility values in various periods, decisions and different states of park is obtained. The results showed that in order to reach to an optimal level of purposes simultaneously, at the beginning of the first 10-year period implementation of ecological decision, at the beginning of the second 10 years period in three considered states for the Sylvan Park implementation of social, ecological and ecological decisions give the most combined utility value of purposes respectively. Results of stochastic dynamic programming showed that implementing the ecological decisions at the beginning of the first 10-year period, implementing the ecological decision by considering the second designed state of park at the beginning of the second 10-year period, and by applying the first designed state of park at the beginning of third 10-year-old period, the implementation of social decisions is desirable to achieve sustainable management in Saravan Sylvan Park. According to the findings, the implementation of these determined decisions can be useful and maximum of desirable use from Park potentials in the economic, social - recreational and conservation and sustainability of indigenous species problems, and reposit the park to the next generation with the best condition

Ecosystem services and economic values provided by urban park trees in the air polluted city of Mashhad

Estimates of air pollutant removal by urban park trees in heavily polluted city of Mashhad, Iran, the associated economic value and the impact on air quality improvement are the main contributors of this study. The economic value of Mellat Park is substantial with a benefit-cost ratio at 0.6; however, the design of Mellat Park has not been adopted in accordance with air quality condition. While carbon emissions is not substantial, a significant part of Mellat Park's value (53.5 %) arises from carbon sequestration. Regarding PM2.5, the most harmful air pollutant, there was a decline in air quality. The economic analysis of the park's three most frequent and three most valuable species highlights the inconsistency between the tree species and the environmental demands. If Acer rubrum (the most valuable species) or Paulownia (the second most valuable species) had been planted rather than Platanus orientalis (the most common species), the park's tree value would have seen 2.7 times increase and a 41.8 % boost. Local scale design considering the link between air pollution and vegetation configuration -including landscape for vegetation and superior plant species - can maximize value of the park's trees on removal rates and air quality improvement

An Optimization Model for Kardeh Reservoir Operation Using Interval-Parameter, Multi-stage, Stochastic Programming

The present study investigates water allocation of Kardeh Reservoir to domestic and agricultural users using an Interval Parameter, Multi-stage, Stochastic Programming (IMSLP) under uncertainty. The advantages of the method include its dynamics nature, use of a pre-defined policy in its optimization process, and the use of interval parameter and probability under uncertainty conditions. Additionally, it offers different decision-making alternatives for different scenarios of water shortage. The required data were collected from Khorasan Razavi Regional Water Organization and from the Water and Wastewater Co. for the period 1988-2007. Results showed that, under the worst conditions, the water deficits expected to occur for each of the next 3 years will be 1.9, 2.55, and 3.11 million cubic meters for the domestic use and 0.22, 0.32, 0.75 million cubic meters for irrigation. Approximate reductions of 0.5, 0.7, and 1 million cubic meters in the monthly consumption of the urban community and enhanced irrigation efficiencies of about 6, 11, and 20% in the agricultural sector are recommended as approaches for combating the water shortage over the next 3 years

Reliable Water Supply System Design under Uncertainty Case Study: Zayandehroud River Basin

Water distribution network system includes multiple sources of supply and demand centers. Uncertainty in the amount of demand and supply on these systems causes many problems for decision-makers and designers. Various methods were proposed to overcome the uncertainty problem in these systems. In this study, to allocation of water in the water supply network of Zayandehrud basin, optimization with degree of conservative (degree of uncertainty) controller parameters were used. The objective function of the study was to minimize the water distribution network costs. A 15-year design and operation period (2024-2009) including two 5-year course designed to expand and create new facilities and a 10-year period of operation in the water distribution network was considered. The results showed that the total cost of development of water distribution networks in the study area is 1/31 billion dollars. Based on the findings, increased groundwater fed ponds to compensate for water shortage in the groundwater resources is recommended. In addition, Increase irrigation efficiency reduces costs related to the water distribution network of agricultural sector

Prioritize the use of Kashmar plain agricultural lands by Gusing multi criteria programming (VIKOR)

The drought Phenomena and its consequences reduce the level of groundwater, lack proper nutrition, dry surface water resources and more harvest of the groundwater resources substantially the sum of these cases is Cause transfer the salty waters to ground water table and will limit capacity required harvest from aquifer and quality of the water. The VIKOR method was applied to determine the best feasible solution according to the selected criteria including the region rainfall situation during different years, soil permeability, land slope and water quality indicators, including SAR, RSC, salinity for determine of groundwater resources quality and land- use restrictions in Kashmar plain in east-north of Iran. The results of sampling in the Kashmar Plains showed that water quality decreased in move path from north to south the groundwater table of Kashmar plains. The use of groundwater resource excessively, downfall of the groundwater level and followed to salinity increased, has been caused to decrease of agriculture water quality and the land- use restriction. Furthermore, the results of the model in years 2008 and 2010 showed that to continue the current form indiscriminate harvesting of groundwater resource due to is the advancing front of salinity to upstream regions with low salinity. Therefore, it is necessary for sustainable management of groundwater resources, control the indiscriminate harvesting and minimizing damage to the groundwater table of the county, experts perform limits the use of agricultural land with the modified cultivated model, the use of deficit irrigation methods

The impacts of climate change on wheat production: A Stochastic production function approach

The purpose of this study was to evaluate the impacts of climate variables on yield and risk of Iran’s wheat production. In this context, crop year data were collected from 1982-83 to 2014-15. Considering crop season, monthly data were aggregated into seasonal data. Iran was divided into four climatic zones. To the optimal selection of predictor variables, Feiveson algorithm was applied. To test the effect of climate variables on wheat production, a Just-Pope stochastic production function was used for each zone. To estimate the panel with fixed effect model, considering the volume of data, Feasible Generalized Least Squares (FGLS) approach was applied. Overall, the results showed that the effects of temperature and precipitation indices are regional; these zones are differently affected by climate indices. Yearly climatic variability has created adverse conditions; However, in some zones, these impacts are negligible; Iran is in the exposure of relatively dry climate with hot summers and cold winters, and extreme temperatures annual events and irregular rainfall changes over the past years have made these farmers more resilient and adaptable

Prioritize the use of Kashmar plain agricultural lands by using multi criteria programming (VIKOR)

The drought Phenomena and its consequences reduce the level of groundwater, lack proper nutrition, dry surface water resources and more harvest of the groundwater resources substantially the sum of these cases is Cause transfer the salty waters to ground water table and will limit capacity required harvest from aquifer and quality of the water. The VIKOR method was applied to determine the best feasible solution according to the selected criteria including the region rainfall situation during different years, soil permeability, land slope and water quality indicators, including SAR, RSC, salinity for determine of groundwater resources quality and land- use restrictions in Kashmar plain in east-north of Iran. The results of sampling in the Kashmar Plains showed that water quality decreased in move path from north to south the groundwater table of Kashmar plains. The use of groundwater resource excessively, downfall of the groundwater level and followed to salinity increased, has been caused to decrease of agriculture water quality and the land- use restriction. Furthermore, the results of the model in years 2008 and 2010 showed that to continue the current form indiscriminate harvesting of groundwater resource due to is the advancing front of salinity to upstream regions with low salinity. Therefore, it is necessary for sustainable management of groundwater resources, control the indiscriminate harvesting and minimizing damage to the groundwater table of the county, experts perform limits the use of agricultural land with the modified cultivated model, the use of deficit irrigation methods

Sustainable Management of Saravan Sylvan Park Using Stochastic Dynamic Programming

The present study sustainable management of Guilan Saravan Sylvan Park was planned. The used method in the form of decision support model in three10-year period was studied for parks of various states and with considering the economic, ecological and social criteria during the years 2008 to 2038. By using hierarchical fuzzy analysis method, the reaching to an optimal level of economic, ecological and social simultaneously and as their combined utility values in various periods, decisions and different states of park is obtained. The results showed that in order to reach to an optimal level of purposes simultaneously, at the beginning of the first 10-year period implementation of ecological decision, at the beginning of the second 10 years period in three considered states for the Sylvan Park implementation of social, ecological and ecological decisions give the most combined utility value of purposes respectively. Results of stochastic dynamic programming showed that implementing the ecological decisions at the beginning of the first 10-year period, implementing the ecological decision by considering the second designed state of park at the beginning of the second 10-year period, and by applying the first designed state of park at the beginning of third 10-year-old period, the implementation of social decisions is desirable to achieve sustainable management in Saravan Sylvan Park. According to the findings, the implementation of these determined decisions can be useful and maximum of desirable use from Park potentials in the economic, social - recreational and conservation and sustainability of indigenous species problems, and reposit the park to the next generation with the best condition

Optimization Model of Hirmand River Basin Water Resources in the Agricultural Sector Using Stochastic Dynamic Programming under Uncertainty Conditions

In this study, water management allocated to the agricultural sector’ was analyzed using stochastic dynamic programming under uncertainty conditions. The technical coefficients used in the study referred to the agricultural years, 2013-2014. They were obtained through the use of simple random sampling of 250 farmers in the region for crops wheat, barley, melon, watermelon and ruby grapes under the scenarios of drought, wet, normal, and water required in the most sensitive growth stages. Production function and profit function were obtained from the yield-water-product function of crops using Eviews software. Expected net profit of the system and optimal allocation of water were also calculated based on the GAMS economic analysis software. The results revealed that 14% of the cases over the past 30 years had wet years (high), 47% of the time and that 39% had experienced drought (low) and normal (average) years. In the best case, i.e. with high current levels, respectively at, 58, 67, 54, and 48% of water requirements for these crops and, in the worst case (with low current levels), 47, 35, 49, 53 and 48% of the water requirements provided during the most sensitive growth stages. Moreover, the results showed that the cultivation of the ruby grape was the best product with the highest expected profit in normal and rainfall conditions. In general, when the expected value of net profit is positive, managers would act optimistically and they would promise the optimal level of water provided to the farmers. Conversely, when the net value is negative they would prefer to be more conservative and would promise a lesser amount of water provided to the farmers. Hence, if the promised water to the farmer is not wasted, he will choose the loss incurred from a lesser harvest