فصلنامه اقتصاد کشاورزی و توسعه
پیاپی 116 (زمستان 1400)

Input prices are one of the main components in determining the price of poultry meat and identifying the factors affecting the input prices is one of the major issues faced by governments. Thus, this study aimed at identifying the relationship between the input prices used in poultry sub-sector and exchange rate volatility in Iran. For this purpose, the Nonlinear Autoregressive Distributed Lag (NARDL) approach and seasonal data were used for the period of spring 2004 to winter 2018. Regarding the seasonality of the data, the HEGY stationary test was used to investigate the presence of seasonal and non-seasonal unit roots. The results showed that the prices of all inputs except for domestic fish powder were cointegrated with GDP and exchange rate volatility; also among the inputs of poultry sub-sector, the domestic corn price had an asymmetric behavior against exchange rate shocks in the either short-term or long-term, while the prices of foreign corn in the short run and compounded feed of laying hens in the long run had asymmetric behavior. According to the asymmetric behavior of corn input price in the face of exchange rate volatility, and given that this corn input accounts for more than half of the poultry feed, using appropriate exchange rate policies and stabilizing the process of these policies can help further stabilize the poultry market; in addition, it would be incorrect and biased to consider the absolute value of the effects of foreign exchange policies on input prices in both short and long terms due to its asymmetry.

One of the most important economic policies in most countries is to support producers or consumers through subsidies; and green subsidies are designed for farmers to achieve the prosperity of business and industry in the agricultural sector. The present study was conducted to investigate the effects of Iran's accession to the World Trade Organization (WTO) by calculating the effects of green subsidy application on farmers' welfare using supply function estimation within a Computable General Equilibrium (CGE) model. Thus, the simulated green subsidy policy in the agricultural sector was designed through 20%, 50% and 100% scenarios and also the model calibration was done using the social accounting matrix of 2011 and the baseline scenario (zero percent of green subsidy applications). In addition, GAMS software was used to analyze the research information. The results showed that during Iran's accession to the World Trade Organization, followed by the implementation of the simulated green subsidy policy, production in the agricultural sector would increase and the prices would decrease while production in industry and services would decrease and the prices would increase. In general, the results of the observed changes indicated an increase in producer welfare in all sectors, with the difference that in the agricultural sector, these changes would be much greater.

Since 1995, Iran has been striving to liberalize its trade regime in order to increase its growth and trade performance. Despite a long period of liberalization, imports are still growing faster than exports, widening the trade deficit. Therefore, this study aimed mainly at investigating the effects of trade liberalization on the growth and trade of agricultural products using the Markov-switching model approach and annual time series data (from 1986 to 2018). The results showed that liberalization, by reducing the import tariff rate, increased exports by 1.56 percent in the short run, but reduced imports by about 7.65 percent in the long run. In addition, the results of growth pattern estimation showed that the liberalization index in both regimes had a significantly positive effect on agricultural growth, meaning that the implementation of trade liberalization policy in the studied period had a positive effect on agricultural growth by 1.98 percent. Thus, trade liberalization in the short run leads to growth in exports and in the long run, by increasing production, increases the volume of exports and decreases imports, and hence, leads to economic growth. According to the obtained results, in order to increase the trade potential of the agricultural sector, it is suggested that tariff policies on trade liberalization be developed in line with the objectives of the Perspective Document Programs of the country.

Due to the limited and scarcity of resources, determining the sectors in which investment stimulates the economy and causes more economic growth, has always been focused by many economic planners. Therefore, in the present study, the key sectors in the Iranian economy were determined by calculating the backward and forward linkages based on the 2011 social accounting matrix of the Islamic Parliament Research Center (IPRC). The results showed that in terms of backward linkage in the sectors of industry (4161.9 trillion rials), agriculture (1422.8 trillion rials), trade (1396.6 trillion rials) and services (1280.8 trillion rials) had priority over other sectors while in terms of forward linkage, the sectors of industry (6053.04 trillion rials), construction (2103.3 trillion rials), services (1992.2 trillion rials) and agriculture (1486.2 trillion rials) were respectively prioritized; in addition, the industrial, agricultural, and services sectors ranked higher in both the backward and forward linkages, respectively. Therefore, considering the determination of the mentioned key sectors, it is expected that directing resources and increasing investment in the development of these sectors can contribute to the economic growth of the country.

One of the most obvious aspects of poverty is the apparent link between this phenomenon and the degradation of natural resources, which leads to environmental instability. In the present study, the relationship between poverty and natural resource degradation in Iran was investigated within the VECM model in the period 1994-2018. The study results showed that the first break of poverty had a positive and significant effect on the degradation of natural resources and a one percent increase in the poverty index would increase the amount of natural resources degradation by 0.19 percent, but the value added of agriculture had a negative effect on natural resources degradation and with a one percent increase in value added, the natural resources would be less extracted by 0.20 percent; also, energy price liberalization and trade liberalization had negative effects on the natural resources degradation while the food security index had a positive and significant effect on the natural resources degradation, so that for every one percent increase in the food security index, the rate of natural resources degradation would increase by 0.78 percent. In addition, according to the study results, energy efficiency has a negative effect on the rate of natural resources degradation with a coefficient of -0.21, but this rate is not significant. The coefficient of the ECM variable is equal to -0.59, which is statistically significant at the level of 95 percent and is in accordance with the theory and indicates that in each period, 59.77 percent of the imbalance error will disappear; also, providing the fuel needed by the rural people, providing subsidies and facilities for the use of new technologies to improve productivity as well as supporting producers and consumers in a targeted way to reduce the degradation of natural resources and protect the environment will be helpful.

One of the most important problems in the agricultural sector is the lack or deficiency of processing of agricultural products; however, in processing two products including sugar beet and sugarcane, Iran has a suitable position in the world, being able to expand this activity by creating the necessary infrastructure and attracting private and public investments through the capital market, and provide the ground for relative self-sufficiency in sugar industry. In the present study, by examining and identifying macroeconomic variables affecting the stock returns of the sugar industry in the Iranian Stock Exchange in the period 2010 to 2019 using the genetic function approximation algorithm, the effect of shocks of these variables on the returns of such stocks was examined using panel vector auto-regression method. The study results showed that among the six macroeconomic variables, the variables of government exchange rate, OPEC oil prices and liquidity volume had significantly positive effects on the stock returns of the sugar industry, so that with the increase of these variables, the incentive to invest would increase in the sugar industry; however, land prices had a significantly negative effect on the stock returns of the sugar industry, because with the increase in prices in the land market, the incentive to invest in this market would increase and, consequently, investment to buy shares in the sugar industry would decrease. According to the impulse reaction functions, the reaction of the sugar industry stock returns to the government exchange rate was initially negative and then, from the second period onwards, increased, and the sugar industry stock return reaction to the OPEC oil price shock have been effective and upward up to five periods; and also, the reaction of the sugar industry stocks to the shock of the variables of liquidity volume and land prices at the beginning of the period was upward and then, from the third to the fifth period, was downward. According to the study results, it is suggested that with the increase of government exchange rate, OPEC oil prices and liquidity, the management of the sugar industry should try to attract more financial resources from the capital market so that with more investment, it could pave the ground for the development of this industry and self-sufficiency in processing of this strategic product. Policymakers are also advised to prevent capital outflows by controlling price fluctuations in parallel markets.

Over the last two decades, water markets have been considered as a desirable demand management strategy to address water scarcity. Accordingly, it is important to assess the impacts of water market formation on the livelihood of farmers in order to plan for the implementation of this policy in the agricultural sector. In the present study, the effects of water market formation on the changes in crop pattern and farmers' gross margin were investigated. The required data were collected in a multi-stage random sampling method from 100 farm-operators with water quota in Ramjerd Plain Irrigation Network; then, the positive mathematical planning (PMP) model was prepared and the water market formation scenario was implemented, considering an equilibrium price. The results showed that the formation of the water market would increase the area under cultivation of high-yielding crops with high water requirements including rice, tomatoes and sugar beets by 40.67, 23.17 and 10.45 percent, respectively. Also, with the formation of the water market, the gross margins of agricultural activities in all parts of the Ramjerd Plain would increase; accordingly, the gross margins of the total plans of lands with water network quota would improve from about 2194.200 to 2013.080 billion rials (equivalent to nine percent). Therefore, creating a water market can improve the economic efficiency of the region, which obviously requires the adoption of effective rules and regulations and close monitoring of this market. Establishing and strengthening local agricultural water institutions and organizations with legal positions can pave the ground for establishing and monitoring the water market.

In today's world, water supply and demand management plays a pivotal role in organizing and planning the drinking water supply of urban and rural residents as well as the water supply of farmers and industrialists, especially in the current situation which all countries are facing the consequences of climate change. Therefore, in this study, the water demand of the agricultural sector of the Caspian littoral provinces was predicted by Markov-Switching method and compared with the Artificial Neural Network model using seasonal data for the period 2001: 1 to 2018: 4. Comparing the efficiency of water demand models estimated by Markov-Switching and ANN methods using Mean Square Error (MSE), Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and Mean Absolute Percentage Error (MAPE) Showed that Markov-Switching approach was more efficient than water ANN models for predicting water demand. In addition, the forecast of agricultural water demand for both seasonal and annual periods was made for the periods of 2019: 1 to 2023: 4 and 2019 to 2023, respectively.

Iran's economy has been hit hard by economic sanctions over the past four decades with varying degrees of intensity. Despite the lack of direct sanctions on the agricultural sector, it is expected that the macro variables of this sector, including its economic growth, will not be immune to the secondary and indirect effects of sanctions. Therefore, this study aimed at investigating the effects of economic sanctions on the economic growth of Iran's agriculture by estimating the linear ARDL model using the statistics of 1992-2019. The study results indicated, on the one hand, the positive and significant impact of net agricultural capital inventory, agricultural labor and productivity of net agricultural capital inventory and on the other hand, no significant impact of economic sanctions on Iran's agricultural value added in the short and long run. In order to maintain the economic growth of the agricultural sector in the face of sanctions, it is suggested that increasing investment in the agricultural sector, reducing agricultural depreciation, increasing the employment of agricultural graduates and adopting policies to support agricultural production might be emphasized by the policy-makers.

Agriculture is one of the most important economic sectors in Iran and its growth is important for food security. Therefore, it is necessary to identify the determinants of agricultural sector. One of these factors is bank credits that provide investment opportunities for entrepreneurs. Some economists believe that the type of bank ownership (public or private) affects the relationship between the variables of bank credit and economic growth. Some of them are in favor of more government intervention and others are against government intervention in the payment of banking facilities. However, in previous domestic studies, the role of bank ownership has rarely been considered. Thus this study aimed at investigating the effect of bank credits on the growth of the agricultural sector with emphasis on the role of bank ownership. For this purpose, ARDL and Fuzzy-ARDL methods as well as quarterly data from winter 2009 to spring 2018 were used. The study findings showed that in Iran, investment enhanced the growth of the agricultural sector, but the increase in labor had a negative effect on it. In addition, the results showed that the facilities granted by state-owned banks were more effective than the facilities of private banks on the growth of the agricultural sector; this finding is in line with the views of the proponents of government intervention in the provision of banking facilities. Therefore, it is suggested that the share of state-owned banks in granting banking facilities to the agricultural sector be higher than that of private banks.For this purpose, the ARDL and Fuzzy-ARDL method is used. The used quarterly data cover winter 2009 to spring 2018. The results show the credit of state banks have more effect on agricultural growth in comparison to the credit of private banks.