فصلنامه اقتصاد کشاورزی و توسعه
پیاپی 114 (تابستان 1400)

Non-certainty is a prominent feature of real world issues. Since the change in the input data, though small, can dramatically change the results of the DEA models, applying ways to deal with non-certainty is an inevitable aspect of the use of these models. Therefore, in this research, the combination of robust optimization with Data Envelopment Analysis was used to study the technical efficiency of broiler farms with the capacity of over 30,000 broilers in Sari city. The results of Robust Data Envelopment Analysis model indicate that in the given uncertainty level (ε=0.1), as the level of conservatism increases from 0 to 8, the average of efficiency scores decreases from 96 to 93 percent and the number of efficient farms decrease from 23 to 18 farms. In addition, the greatest difference between the amount of optimal and actual consumption of inputs belongs to the cost of taking drugs and vaccines. Given that the largest part of drugs and vaccines costs are spent when a disease spreads, Applying appropriate policies to prevent the spread of epidemic diseases such as choosing healthy broilers in the same age, using proper nutrition, providing comfortable aviary, choosing proper density of broilers, dissolving the carcasses of ill broilers, using disinfectants properly and also using experts to determine the appropriate time and amount of drugs and vaccines can greatly help to enhance the efficiency of inefficient farms.

The purpose of this study is to simulate and evaluate the water market's efficiency and compare it with the law of optimal allocation of water and allocations based on fixed and proportional quotas. The study area is located in the Jiroft sub basin in the Hali Rood watershed and data are for 2015 which were obtained from the Agricultural Jihad Organization of southern Kerman province. The method used is calculate the benefit from irrigation and minimize income losses in the entire region. For this purpose, the first 20% and 30% restrictions was imposed on use of groundwater resources, and then the effects of optimal allocation law, allocations based on proportional and fixed quotas on the benefits of irrigation were investigated. Subsequently, through the water market simulation, the market performance was analyzed after the implementation of these rules. To investigate the effect of transaction costs on water trade, transaction costs were considered, zero, 5, 10, 20 and 30 percent of water price. Based on the results, if the conditions of perfect competition are on the market and transaction costs are zero, the optimal allocation and formation of the water market will result in the same final allocation of water rights and irrigation benefits for the whole region. Also, by reducing the availability of water resources, the benefits of water trade will increase and with increasing transaction costs, reduces the volume of water exchanged and the gains from trade.

Fishing is one of the most important economic activities in providing food security and livelihoods locally and globally. Fishing in the Persian Gulf also has the potential for Iran that can strengthen its position GDP of the agricultural sector. This study, with an overview of the fishing situation in the Persian Gulf, aims to present a detailed picture of this activity in southern Iran and its problems that can be used in order to exploit its potential and improve current conditions. The objectives of the study were followed by a combined SWOT-Fuzzy TOPSIS approach based on the opinions of experts in the field of fisheries in the south of Iran in 2018. The results of this study can be used as management strategies for enhancing fishing and exploiting fishing opportunities in the Persian Gulf, so that its potential can be exploited, while reducing the pressure on fish stocks. Based on the results, it was suggested strategies for enhancing fishing infrastructure in southern Iran, enhancing fishing technologies as high-efficiency fishing tools, establishing a modern fishing zone, stock assessment and developing laws according to its conditions, stock enhancement with fishing habitats and prioritize improved value-added fishing with modern marketing and the use of modern processing techniques.

Consumer behavior and preferences among households’ milk may be in different time periods, different. It is important to change behavior in the studied time period specified by identifying changes in people's behavior, can be used to evaluate policy payments made or implemented new policies. The purpose of this study was to investigate the structural stability or break of Iranian consumers’ preferences for pasteurized and non-pasteurized milk. In this regard, using the cost and income statistics of urban and rural households’ in Iran Statistics Center in the period 1990-2016. Also to analyze household preferences, from a non-parametric pre-disclosed test (WARP) and Kruskal-Wallis statistics (K-W) have been used to distinguish permanent structural changes from fleeting shocks. For this purpose, the matrix of poorly expressed preferences was compiled using the average price and quantity of pasteurized and non-pasteurized milk in urban and rural areas, and by comparing consumer choices in different time periods. The results of the WARP matrix indicate a contradiction in the preferences of consumers of both pasteurized and non-pasteurized milk. In other words, the rational behavior of consumers of pasteurized milk and non-pasteurized milk is rejected in Iran. Also, the results of the K-W statistic indicate a structural change in 1995, indicating a structural failure in the preferences of Iranian consumers for milk. As a result, in future studies, it is suggested that special attention be paid to behavioral economics and consumer preferences for important products such as milk.

Food security and public health have had a specific position in large-scale governmental policies in the last two decades, according to the Food and Agriculture Organization (FAO). Iran is no exception. The food security and food health of Iranian families should be particularly considered, given the fact that their purchasing power has declined. Thus, the present study aims to investigate factors influencing food insecurity in Iranian urban families. Data were collected from 18704 urban families in different Iranian provinces based on the consumption of nine necessary food groups. Generalized ordered logit models were employed. The results indicated that 73% of the urban families were food secure, while the remaining 27% were food insecure. Moreover, the estimation of the final effects for the Generalized logit model showed that gender, age, homeownership, personal automobile, family size, and income had significant effects on food insecurity in different urban groups. According to the results, Kermanshah Province had the highest level of food security, while Kerman and Hamedan Provinces were at the lowest level of food security. Since two high-risk groups were identified in terms of consuming calories, it is recommended to make targeted policies to balance the two groups. The results also implied the higher food security of families with female householders than that of families with male householders.

The aim of this study is to investigate how to influence temperature and rainfall on cost efficiency of wheat production. For simulate the effect of temperature and rainfall on cost efficiency of production, Information on pricing, yield per hectare, the production cost per hectare, the average temperature and rainfall during planting crops, for wheat and for 28 provinces were collected over a period of 10 years. by investigation, Different methods of stochastic frontier cost function with panel data, Stochastic Frontier "panel data" Method was selected. After estimating model, Delta method used to simulate the effect of rainfall and temperature variables on frontier cost. And the impact of these two variables was estimated on cost frontier and finally, on the cost efficiency. The results showed that, Khuzestan has highest cost efficiency and Yazd has lowest cost efficiency in wheat production. And increased temperature and rainfall in the range of climatic conditions up to about 4% is effective on the cost efficiency.

In this study, a Simultaneous Compromise Constraint method was used for optimal allocation of limited water resources between different economic sectors of Yazd province by emphasis on agricultural sector. The novelty of the present study is the renovation of the aforementioned method by addition an extra constraint (employment constraint). The results of the study indicate that, based on the water allocated to the different sectors, 5.2 percent annual growth (at a fixed price) will be achieved in the year 2020, in comparison to the base year. The ratio of employment to the expected objective will be about 98.8%. Due to reduction of available water, the main pressure will be on the agricultural sector, the efficiency of the model in the optimal attention to simultaneous multiple goals, causes water allocation to be such that even the agricultural sector has an annual economic growth of 0.4. The results indicate that, the method has a high ability to compromise between goals and optimal allocation of water resources in order to achieve the goals in accordance with the facts. Therefore, the proposed model could be considered as a suitable method for providing water sector plans.

Paying attention to the development chain, which also includes the supply chain and the value chain; is essential to preserve, revive, and develop traditional products. In this regard, awareness of the importance and position of traditional products such as woolen products and provide solutions to boost production and their presence in domestic and foreign markets, can be helpful. The main goal of this study was to determine the strengths, weaknesses, opportunities, and threats (SWOT) of the production and supply chain of woolen products in Rezvanshahr County. Research data were collected based on face-to-face interviews with 30 local experts in 2018 through the available sampling method. Using the SWOT matrix, a strategy was developed for the production and supply chain of woolen products in this county. The results showed that the strategic position of production and supply chain of woolen products in Rezvanshahr County was in the first place. Being located in this area, so-called invasive units (SO), a strategy entitled the development chain (revitalization and maintenance in the first stage and development of the production and supply chain of woolen products in Rezvanshahr Couty in the next stage) was suggested.

Considering the fact that the price of energy carriers has a significant impact on the final cost of agricultural products, removing the subsidies of energy carriers will have multiple effects on the agricultural sector. The purpose of this study was to investigate effects of reforming the subsidies of energy carriers on agricultural products, consumer price index, demand inputs, and carbon dioxide emissions using the Autoregressive-Distributed Lag model for the annual data from 1988 to 2015. These data were collected from the Central Bank, the Statistics Center of Iran, the Ministry of Energy, and the Food and Agricultural Organization. The results showed that eliminating electricity subsidies has more negative economic and social effects than eliminating gas oil subsidies. the elimination of electricity subsidies reduces production and capital by an average of 1% and 41/13%, respectively, while the elimination of gas oil subsidies reduces production and investment by an average of 0/7% and 20/4%, respectively. Moreover, the consumer price index and the demand labor in the elimination of electricity subsidies were in average 12/3% and 1/38%, respectively, while in the elimination of gas oil subsidies, they were in average 3/14% and 0/55%, respectively. In the study of short-term models, it was revealed that the effects were similar to those of long-term models but with less impact. It is suggested that the elimination of gas oil and electricity subsidies in the agricultural sector be done gradually and that the elimination of gas oil subsidies be given priority over the elimination of electricity subsidies.

Today, one of the most important challenges in maintaining the stability and sustainability of regional and national economic development is the phenomenon of climate change and its consequences, which is a serious threat to natural systems, water resources and social and economic well-being. Therefore, understanding the relationship between climate change and socio-economic variables such as food security and economic welfare, is necessary.This research aims to evaluate the impact of climate change on food security and economic welfarein the Hamadan-Bahar plain. In this regard, the variables of rainfall and temperature for the horizon of 2070 were predicted underselected climate scenarios and by estimating yield response functions, the products yield changes due to climatic parameters were measured. Finally, by developing a nonlinear mathematical planning model including economic, agronomic and meteorological dimensions, the potential effects of climate change on economic welfare and food security under the selected climatic scenarios in 2070 horizon compared to 2018(baseline) were evaluated. The results showed that climate change on the 2070 horizon would reduce water access, food production and supply, and ultimately reduce consumer welfare surpluses and increase food prices. Accordingly, the farm income would increase but still total economic welfare decline. On the other hand, the largest reduction in consumer surplus in all scenarios is related to strategic products that provide food security. However, the strategy of improving irrigation efficiency by 4.7, 20.8, 5.5 and 24.1%, respectively in scenarios B1, A2, RCP2.6 and RCP8.5, will be completely neutralize welfare losses due to climate change.