j. hosseinzad

Rice is a crucial agricultural product, and enhancing its productivity is essential for increasing production. This study aims to analyze the total factor productivity growth of rice production in Iran from 2000 to 2020. Using parametric (stochastic frontier analysis) approaches, the research evaluated the rice productivity growth and its components, including scale and technological changes. Based on the estimated Translog Cost Function, the annual total factor productivity growth was 2.1%, with positive technological change as the primary driver of these improvements. To further enhance productivity, the study recommends utilizing improved seeds, modern machinery, fertilizers, and nutritional solutions during rice cultivation. Additionally, the research suggests the application of parametric approaches in future studies to assess the impact of technological changes on crop yields.

Trade liberalization of agricultural products and its effect on food prices, because of the importance of food in the household consumption basket, is one of the most important goals of governments for public access to health and food security. The present study investigated the effect of trade liberalization on domestic food prices in Iran. In this context, the single-equation error correction model (SEECM) was applied using the required time series data during 1989-2019. The results show that in the short-term, only increases in global food prices, liquidity, and exchange rates significantly affect domestic food prices. However, domestic food prices show more reaction to exchange rate fluctuations than to world prices. The estimated long-run equilibrium relationship demonstrated that world food prices have a positive and trade liberalization has a negative effect on domestic food prices. In addition, in the long run, the effect of liquidity on the domestic food price of food is more than other factors. The estimated error-correction term indicates that in the long run, if a shock occurs to the domestic food price, the domestic market can adjust it by only 35% annually. Considering the fluctuations of global prices and exchange rates, and their impacts on domestic prices, it is necessary to pay attention to these fluctuations in revising trade policies.

In recent years, the problem of water scarcity is becoming one of the most challenging issues with the economic development and population growth that have involved many sectors due to its importance and economic status and has received increasing attention from governments and international research organizations. This emphasizes the need for optimal allocation of mentioned resources to balance socio-economic development and save water. Therefore, the aim of this study is to develop an uncertainty-based framework for agricultural water resources allocation and calculate the amount of water shortage after allocation and also risk evaluation of agricultural water shortage. The developed framework will be applied to a real case study in the Marand basin, northwest of Iran. Perception of the amount and severity of risk on the system can be a good guide in the optimal allocation of resources and reduction of damage.

Since various uncertainties exist in the interactions among many system components, optimal allocation of agricultural irrigation water resources in real field conditions is more challenging. Therefore, introduction of uncertainty into traditional optimization methods is an effective way to reflect the complexity and reality of an agricultural water resources allocation system. Among different methods, inexact two-stage stochastic programming (ITSP) has proved to be an effective technique for dealing with uncertain coefficients in water resources management problems. ITSP is incapable of reflecting random uncertainties that coexist in the objective function and constraints. Considering the risk of violating uncertain constraints and the stochastic uncertainty of agricultural irrigation water availability on the right hand side of constraints and uncertainties related to economic data such as the revenue and penalty in the objective function which are expressed as probability distributions, the CCP method and Kataoka’s criterion are introduced into the ITSP model, thus forming the uncertainty-based interactive two-stage stochastic programming (UITSP) model for supporting water resources management. A set of decision alternatives with different combinations of risk levels applied to the objective function and constraints can be generated for planning the water resources allocation system. In the next step, on the basis of results of UITSP agricultural irrigation water shortage risk evaluation can be conducted by using risk assessment indicators (reliability, resiliency, vulnerability, risk degree and consistency) and the fuzzy comprehensive evaluation method.

A series of water allocation results under different flow levels and different combinations of risk levels were obtained and analyzed in detail through optimally allocating limited water resources to different irrigation areas of Marand basin. The results can help decision makers examine potential interactions between risks related to the stochastic objective function and constraints. Furthermore, a number of solutions can be obtained under different water policy scenarios, which are useful for decision makers to formulate an appropriate policy under uncertainty.The results show that the dry season, i.e., July, August and September are the peak periods of water allocation and demand in Marand basin, which in these months, despite the higher water demand, the amount of water allocation in the current situation is less, which leads to more water shortages in these months. However, the results show that by increasing the efficiency of irrigation and water allocation using the developed framework, the amount of agricultural water allocation and demand is almost balanced and in addition to reducing water shortages, it leads to control over extraction from wells. Also, the goals of the regional water organization, which is reducing the amount of water allocated in the agricultural sector, will be achieved. Comparison with actual conditions shows that the allocation of water resources using the developed framework reduces water shortages while allocation becomes more efficient. Furthermore, the net system benefits per unit water increase which will demonstrate the feasibility and applicability of the developed framework. Results of evaluation of agricultural irrigation water shortage risks indicate that the water shortage risks in the Marand basin are in the category of serious or critical risk level. Therefore, if the current trend of allocation and exploitation of water resources continues, with the population growth, climate change, increasing demand for agricultural products and changing the probability of available water in the future, the water shortage risk would increase to the unbearable risk level. The continuation of this process threatens all investments and economic foundations of this study area. Therefore, the risk of water shortage in the future should be managed by improving the water-saving technologies and also changing the cultivation pattern to drought resistant crops.

In this study, an uncertainty-based framework for agricultural water resources allocation and risk evaluation was developed, including model optimization of agricultural water and risk evaluation of water shortage. The developed framework is capable of fully reflecting multiple uncertainties. The developed framework will be helpful for managers in gaining insights into the tradeoffs between system benefits and related risks, permitting an in-depth analysis of risks of agricultural irrigation water shortage under various scenarios. The assessment of agricultural water shortage risk based on the results of the optimization model helps decision makers to obtain in-depth analysis of agricultural irrigation water shortage risk under various scenarios. In application of the developed framework to Marand basin, series of results of agricultural water resources allocation expressed as intervals, and agricultural water shortage risk evaluation levels under different flow levels and also different combinations of risk levels are generated. Comparison between optimal results and actual conditions of agricultural irrigation water allocation demonstrates the feasibility and applicability of the developed framework. Results of evaluation of agricultural irrigation water shortage risks indicate that the water shortage risks in the Marand basin are in the category of serious or critical risk level. Therefore, effective risk management measures should be taken first for different irrigation areas of Marand basin.

Ajichay basin is one of the largest agricultural areas and water consumption in Urmia Lake basin. During the recent years, the impact of climate change on one hand, and human factors on the other hand, have changed Ajichay basin to a center of crisis as it has lost its efficiency in supplying water for Urmia Lake. Having the main branches of Ajichay, Sarab county has a great role in crop production and therefore agricultural water consumption compared to other counties around the basin. Therefore, managing water consumption in Sarab County is suggested to resolve the decreased quality and quantity of water in Ajichay basin. Therefore, the aim of the current study is to investigate the impact of climate and water management scenarios on water resources, cropping pattern, yield, and profits of farmers in Sarab County. To achieve the study aims, the hydro-economic model was used. In the economic section, quadratic risk programming model and in the hydrological section, the WEAP-MABIA model was used. The purpose in quadratic risk programming model is to maximize the expected farmers’ utility to some technical and structural restrictions. Maximum expected utility of farmers which is calculated by subtracting the risk element from the net income for each crop. MABIA uses a two-part crop coefficient. In the dual crop coefficient approach, the effects of crop transpiration and soil evaporation are determined separately. Two coefficients are used: the basal crop coefficient (Kcb) to describe plant transpiration, and the soil water evaporation coefficient (Ke) to describe evaporation from the soil surface. The current study applied HadCM3, as the general circulation model. LARS-WG was used for downscaling climatic generator and producing rainfall, radiation, and minimum and maximum temperature in a station under A2, B1, and A1B emission scenarios. The period 1987-2018 was used as the base and the future considered period was 2018-2050. All required variables such as information about input values, production quantities, and economic information were collected from 210 questionnaires filled by farmers during 2018 which were selected through stratified random sampling. The results showed that the average rainfall decreased in the range of 21-38% under the emission scenarios of A2, B1, and AIB during 2018-2050 period. In the next period of 2018-2050, the average annual temperature will also increase by 2.5 °C compared to the baseline period under A2 scenario. The results of simulations revealed that the crop yields would undergo a decrease after climate change scenarios. The most considerable yield reduction belongs to A2 scenario in which potato will have the highest yield reduction of 17%. The crop yields of barley and wheat shows a slight reduction. Thus, these two products have larger cropping area in the climatic scenarios. The results of climate change indicate a diminishing trend in available water and water supply reliability for agricultural purposes. The available water for irrigation areas had 21.92% decrease after applying climate change scenario. The mean for water supply reliability in the sub-basin decrease from 84.93% to 62.35% if the future years continue to have a decrease in rainfall and increase in temperature. By applying the scenario of agricultural water reduction along with climate change scenario, the profit in each region will decrease compared to the reference scenario. The highest reduction rate belongs to Asbforushan 2 area with 28% compared to the reference scenario.The profit in all the sub-bases had a rise after increasing irrigation efficiency scenario. Thus, applying increasing efficiency scenario, in addition to more useful and efficient use of allocated water, will also increase farmers' profits which offer a better situation than the scenario of reducing the share of agricultural water.Among the studied crops, bean had the highest reduction in cultivation, which stemmed from its high-water requirement. However, potato also had a high water requirement compared to bean but maintained a high cropping area due to higher gross profits. Findings of the current study revealed that wheat and barley had more resistance against the effects of climate change and shifting the patterns of cropping was an adaptive strategy for coping with the effects of climate change.Climate change reduces the labor employment. As Implementing A2 scenario results in a 14.48% decrease in the average of agricultural employment in the area. The agricultural water reduction scenario alone results in 5.9% decrease in labor, whereas the increasing irrigation efficiency scenario has an 8.9% decrease. Applying the agricultural water reduction scenario along with climate change reduces the employment by 17.2% in the region by reducing the area under cultivation of crops that require a lot of labor. The increasing irrigation efficiency along with climate change scenario also results in a 20.9% reduction in labor employment. Overall, the findings of the current study revealed that without changing the management strategies there would be a considerable reduction in crop yield in near future. Optimizing management methods, selection of right time for crop cultivation, optimized harvest, studying the feasibility of cultivating crops with shorter growth period and using cultivars with higher yield are the effective ways to confront the effects of climate change. The analysis of scenarios revealed that policies alone cannot compensate for water problems and there is a need for plenty of scenario for optimum results.

The intensive use of pesticides has posed detrimental effects on the environment. Concerns over those environmental impacts have led to many efforts in pesticides usage reduction. As an example, economic instruments that can be used in explaining suitable policies. With Estimating the economic value associated with pesticide reduction and identifying the effective factors on administration and success of pesticide reduction policies can be assisted in designing pesticide regulations. The purpose of this study is to identify the economic benefits associated with pesticides reduction in Khuzestan province, Iran. The required data were collected from 180 farmers of Khuzestan province in 2009. The study uses Contingent Valuation survey to estimate farmers willingness to reduce three risk level (high, moderate and low) for five environmental categories (human health, birds, aquatic species, beneficial insects and livestock). A Tobit model with heckman two-stage procedure estimates is developed to determine the factors that affect farmers willingness to pay. With calculating the willingness to pay it was found that greater concern is evident for human health, birds and livestock, and relatively less for aquatic species and useful insects. The economic benefits for 15 environmental classes varied from 571623 Rials (human/high) to 56926 Rials (beneficial insects/low) per person per cropping season. The estimate of the Heckman two stage procedure results in determining the decisive factors in willingness to pesticides reduction strategies which consist of income, number of IPM strategies, farmer importance to decrease pesticides risk, farmer perception about environmental impacts, confronting with environmental impacts and own tenure, all with positive effect, while age and pest severity with negative effects. Farther results indicate that the variables of growing vegetables and percentage of IPM strategies have the most positive effect, while cropping corn and daily wage of hand weeding worker have the most negative effect on amount of willingness to pay.

The use of water sources has increased due to extend of agricultural activity for answering food needs of increasing population. While because of exploitation and consumption of water, the use of this restricted resource is not appropriate. Consequently in many districts of country the head level of ground water aquifers have been fallen and water level is negative. So, application of a proper management program in optimal use of these resources seems to be necessary. With respect to the effects of depletion of ground water store through the time, the time is an important variable in solving of optimization problems for these resources. Thus, the application of dynamic models such as optimal control for these cases because of focusing on time is essential. Models are solved in order to maximize the social net benefit subject to stability of aquifer. In this study, optimal control model is applied for Ajabshir plain where is an important agricultural area in Azarbayjan-e- Sharghi. This plain has been faced with limitation and shortage of water supplies and negative water level in aquifer. The optimal extraction path was determined by execution of the optimal control model in this ground water aquifer. The results show that ground water aquifer built- up and reach the optimal steady state in 36 years. Thus ground water extraction would decrease besides another resource (backstop) would be applied to secure demand of farmers during this period of. Subsequently, regard of determined extraction would result in stability of ground water aquifer and on the other hand, it would cause the stability of agricultural activities as well as increase of farmer's revenue.

The important policy of any nation in to reach the maximum possible welfare levels and lowest misery rates at lowest possible social costs and highest speeds. Hence, in this study the human development index (HDI) is reviewed, then these criteria are studied in the villages of East Azarbaijan using the 2007 official database. For this purpose, the criteria of life expectancy, rate of literacy and rate of education facility are measured. Accordingly, the average HDI for whole rural areas of the province was 0.614: i.e. at medium rates. The successive ranks are Tabriz, Maragheh, Malekan, Oskoo, and Marand showing inequality of HDI in different cities. This was due to the differences in inequality and in satisfactory rates of education and health facilities. Therefore, more investments in education, health and income augmentations devices are recommended.

Supporting agricultural products with some rates of comparative advantage is an important step for non-oil exports development of Iran. The purpose of this study is to identify the agricultural products of East Azarbaijan with comparative advantages by policy analysis matrix (PAM). The effects of exchange rates and global prices on the comparative advantage of the cases are examined. The dry farmed wheat (DFW), dry farmed barely (DFB), and irrigated barely did not show any rates of comparative advantages; while, cucumbers, and tomatoes exposed the highest rates of comparative advantages. The sensitivity analyses of comparative advantage indices with respect to the exchange rates(ER) demonstrate the positive correlation; where, DFW, and DFB had highest response rates; and the cucumbers had the lowest response for ER changes. Sensitivity analyses of comparative advantages with respect to global prices showed the deletion of comparative advantages with 25% declines in global prices of irrigated wheat, and locating the potatoes on breakeven point. Sensitivity analyses of tradable inputs costs confirmed that by increasing the ratio of incomes to tradable input costs decrease the response of domestic resource costs indices as compared with tradable input costs changes.

The production unit size is one of the effective factors in optimum uses of inputs. Since optimum size is affected by the characters and economical conditions in each district, the studies for determining the optimum farm size should be done specially for each crop and each district. In this study tried to determine the optimum rice farm size in Guilan province which is one of the most talented district for rice in Iran applying Translog cost functions to data collected from 280 farmers in the studied district who were selected by two stage random sampling method. The results showed increasing return to scale for all districts and for each town. Also the optimum sizes are 2.17 ha for province, 2.2 ha for Rasht, Somee sara 2.26 ha, Talesh 2.01, Astaneh 1.73 ha and Rudsar 1.47 ha. In general, the optimum sizes are larger than present average sizes. Due to results, encouragement of farmers to form cooperatives and convert of small farm to cumulative farms are recommended.