مجله اقتصاد منابع طبیعی
پیاپی 4 (بهار 1393)

Power plants، as the most important section of electricity industry، are the most environmental pollutants and bring a wide range of environmental pollution such as air، water، soil and sound pollutions. Among them، Air pollution، arising from power plants، is the most important than mentioned pollutions. In this regard، this research is looking for the study of power plants effect on Air pollution in Iran. Alongside with the study of the power plants’ role، as one of the effective factors in Air pollution، we consider the role of other effective factors such as the number of vehicles، economic openness and Gross Domestic Product (GDP) between 1985 and 2010 (1364 -1389) in Iran using the econometric Auto Regressive Distributed Lags (ARDL). The findings show that forsaid variables have a positive and significant effect on diffusion of Co2 in Iran and respectively GDP، power plants، the number of vehicles، trade openness، have the most effects on Air pollution in Iran.

In this article، the behavior of GECF organization has been studied as a two-part cartel. Based on this، the supply side of world natural gas market considered as a monopolistic market in which GECF plays the role of the price maker firm. In the cartel، due to significant differences in the level of reserves of members، we face with a two-part cartel that each of the two parts in the c1artel tends to be leader. However، both know that they cannot be leader in the cartel simultaneously. Then they try to find an optimal solution about the production and pricing that resulted from cooperation and agreement. This study uses annual data from 2010-1980، and optimized the cartel behavior until 2070. To obtain the supply of each of the two parts within the cartel Nash product was used. To solve the Nash product requires an initial point. In this study، unlike previous studies that have used the threat point، a new point has been used that we have called it encouragement point. The results indicate that at first second group is responsible for the majority of extraction in the cartel; and with approaching to check out the group reserves، the first group will became the dominant group in the cartel. Because the second group in compared with the first group has less reserves and higher discount rate، prefer that extract the reserves earlier than the first group. Thus in the first period the second group responds to the growing demand; and then the first group increases the production and will become dominant on the supply side of the market.

As an option for spending leisure time، urban parks bear important recreational values. In this study to estimation theeconomic valuepalatabilityShahidZare Sari Forest Park، recreational value in the area in 2011 years، was estimation using contingent valuation and economic-social factors affecting to them was determinedusing the Logit model. The mean of willingness to pay for recreational value of this park is RLs5081. 05 per visitAlso the recreational annual value is estimated 21523690. 73RLs/ha. The findings also show that the involved variables، visitors’ offer rate، income، read visit and education، were significant at a 1% level statistically and they were the most effective factors in visitors’ WTP for using ShahidZareForest Park. Visitors’ distance was the next effective factors in their WTP in a way that it was found to be significant at a 5% level. Results revealed that forest parks had considerable recreational value that this point can help to programmers and managers of executive، social & economic in the preservation planning and sustainable utilization of natural resources.

Position of the energy sector in the economy with regard to the role of infrastructure، so it is obvious the importance and necessity of planning in the energy sector as part of planning the whole economy to achieve sustainable development will be visible between the energy carrier electricity than other energy carrier، while being effective role in the production and consumption، important in decision making process is economic and social. Two dimensions of electricity supply and demand-based planning in this sector makes up. Therefore، understanding the factors affecting these two dimensions is essential. On the other hand the implementation of legislation targeted subsidies to the electricity prices by eliminating subsidies on domestic electricity demand affects domestic demand must be examined. The aim of this study is that the effect of the bill by targeted subsidies on domestic electricity demand is detected purpose household electricity demand function in two modes is estimated in the first case، using income، price of domestic electricity and natural gas prices And at the second case electricity prices by eliminating subsidies and domestic use of international price ARDL method is estimated is needed to explain the basis or Ranh study the difference between domestic and international prices has been on. The results show that consumer reactions after the elimination of subsidies on electricity prices than domestic income، domestic price of electricity and gas price increases to Tyby. Estimation results about the effects of subsidy removal from two scenarios with abrupt removal and elimination of subsidies within five years، were studied in both scenarios household electricity demand by more than 10 percent reduction does not mean that this is the rising cost of household electricity consumption. The results also show that in the before and after removal of subsidies had the greatest effect on electricity demand of the household income and income effects of policy from politics is more precious.

The phenomenon of air pollution is a consequence of industrial and economic development that is sharply increasing day by day by population and urbanization increase development of transporting and extremely use of fossil fuels. Today this phenomenon has been converted to critical problem of metropolitan. Air Quality Index (AQI) is an enhanced index of Pollutant Standard Index (PSI) and it''s air quality index that indicates that whether air is polluted or not. This index explains the influence of different levels of air pollution on public health and precautions when levels of air pollution increase. The object of this research is to analyze and study on AQI and criteria pollutants changes of air pollution from 1381 to 1391. The results of this research indicate that density of carbon monoxide has been decreased in last decade that is a result of appropriate policy in the field of transport. By the way the mass of pullutions that enter to Tehran is way different with international standards.

The aim of the present study was to determine the causality between economic growth and environmental quality. The variables under study were economic growth، government expenditure، openness degree of the economy، capital stock، population، average export of contaminants، and carbon dioxide (CO2) emissions during the time period from 1977 to 2010 for the Iranian economy. The results suggested that there is a two-way relationship between economic growth and environmental quality. Besides، economic growth was found to have the greatest impact on air pollution.