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Urbanization and mass movement of the population from rural areas and small cities to megacities have led to environmental, economic, and social problems in Iran. In dealing with these challenges, assessing resource and environmental carrying capacity (RECC) is considered an effective method to leverage space and capital to achieve sustainable development. This study aimed to rank the provincial RECC in Iran. Toward this purpose, environmental indices were generated from remotely sensed and statistical census data. Then, the provinces were scored in terms of environmental, economic, and infrastructural carrying capacities, and RECC using the mean variance analysis method. Results demonstrated that in most areas, there is no relationship between economic and infrastructural capacities and development. Statistically, a correlation coefficient of −0.53 between economic and environmental carrying capacities indicated excessive use of environmental capacities. Moreover, the spatial distribution pattern of environmental, economic, and infrastructural carrying capacity was entirely heterogeneous between the provinces; there was a northeast–southwest pattern in terms of infrastructural capacity and an economic pattern from north to south. The distribution pattern of RECC is most consistent with the environmental capacity, pointing at the high weight of the indicators of the RECC model. In conclusion, this research offers a new vision for policymakers and provides a theoretical and applicable framework for implementing sustainable strategies in land-use planning. It is recommended that the RECC concept and tools can be used not only for planning but also for measuring the efficiency of spatial development programs and establishing land balances in the region.  相似文献   
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Environmental Economics and Policy Studies - Economists have long argued over the political economy of tradable emission permits, especially the political pressure of lobby groups on international...  相似文献   
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Environment, Development and Sustainability - In this research, 17 implications of changing cropping patterns (CP) to low water demand plants (LWDPs) were identified. Then, the experts were asked...  相似文献   
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Sulfur dioxide (SO2) is considered as a main air pollutant in industrialized areas that can damage vegetation. In the present study, we investigated how exposure to SO2 and foliar application of iron (Fe) would affect certain physiological characteristics of Plantago major. The plant seedlings exposed or unexposed to SO2 (3900 μg m?3) were non-supplemented or supplemented with Fe (3 g L?1) as foliar spray. Plants were exposed to SO2 for 6 weeks in 100 × 70 × 70 cm chambers. Fumigation of plants with SO2 was performed for 3 h daily for 3 days per week (alternate day). Lower leaf Fe concentration in the plants exposed to SO2 at no added Fe treatment was accompanied with incidence of chlorosis symptoms and reduced chlorophyll concentration. No visible chlorotic symptoms were observed on the SO2-exposed plants supplied with Fe that accumulated higher Fe in their leaves. Both at with and without added Fe treatments, catalase (CAT) and peroxidase (POD) activity was higher in the plants fumigated with SO2 in comparison with those non-fumigated with SO2. Foliar application of Fe was also effective in increasing activity of antioxidant enzymes CAT and POD. Exposure to SO2 led to reduced cellulose but enhanced lignin content of plant leaf cell wall. The results obtained showed that foliar application of Fe was effective in reducing the effects of exposure to SO2 on cell wall composition. In contrast to SO2, application of Fe increased cellulose while decreased lignin content of the leaf cell wall. This might be due to reduced oxidative stress induced by SO2 in plants supplied with Fe compared with those unsupplied with Fe.  相似文献   
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This paper presents an efficient methodology for developing pollutant discharge permit trading in river systems considering the conflict of interests of involving decision-makers and the stakeholders. In this methodology, a trade-off curve between objectives is developed using a powerful and recently developed multi-objective genetic algorithm technique known as the Nondominated Sorting Genetic Algorithm-II (NSGA-II). The best non-dominated solution on the trade-off curve is defined using the Young conflict resolution theory, which considers the utility functions of decision makers and stakeholders of the system. These utility functions are related to the total treatment cost and a fuzzy risk of violating the water quality standards. The fuzzy risk is evaluated using the Monte Carlo analysis. Finally, an optimization model provides the trading discharge permit policies. The practical utility of the proposed methodology in decision-making is illustrated through a realistic example of the Zarjub River in the northern part of Iran.  相似文献   
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Environment, Development and Sustainability - The tourism sectors consume a high amount of electrical power, which in most cases is supplied by the electrical grid and diesel generator. As a...  相似文献   
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In order to assess the chemical properties of groundwater and soil in ophiolitic zone of Firuzabad, in east of Shahrood, Iran, 10 soil samples with regard to sensitive points (vicinity to mine, ophiolitic rocks, and villages) and 10 groundwater samples including nine samples from springs, and also one sample from a well in a village of the study area were taken. These samples were analyzed in laboratories using inductively coupled plasma method. The soil samples were also evaluated for grain size. The obtained results show that most of heavy and major elements were exceeding the permissible levels in soil and water samples in the study area. On the subject of soil quality, concentrations of elements Cr, Mn, Fe, Ca, Mg, Ca, Ni, and Zn are above permissible levels. Enrichment factor and index of geoaccumulation have been calculated for heavy and major elements of all soil samples. According to the obtained results, it may be argued that soil samples are contaminated in relation to the above-mentioned indices. Comparing the concentrations of elements with results of grain size analysis illustrates that the concentrations of Cr, Ni, Fe, Mg, and Co are positively correlated with sand fraction and the concentrations of Al, P, Mn, and Pb are directly proportional with clay fraction in soil samples. The study on water contamination suggests that concentrations of elements Cr, Ni, and Mg in groundwater samples of the study area are above the permissible levels. Some indices like metal index and heavy metal pollution index show that most of the water samples include heavy metal contamination.  相似文献   
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A novel nanomaterial has been developed for speciation of Cr(III) and Cr(VI) in water and soil samples. In this study, a new type of alumina-coated magnetite nanoparticles (Fe3O4/Al2O3 NPs) modified by the surfactant Triton X-114 has been successfully synthesized and used in magnetic mixed hemimicelles solid-phase extraction procedure. The procedure was based on the reaction of chromium(III) with 1-(2-pyridilazo)-2-naphtol as a ligand, yielding a complex, which was entrapped “in situ” in the surfactant hemimicelles. The concentration of chromium(III) was determined using flame atomic absorption spectrometry. After reduction of Cr(VI) to Cr(III) by ascorbic acid, the system was applied to the total chromium. Cr(VI) was then calculated as the difference between the total Cr and the Cr(III) content. This method can also be used for complicated matrices such as soil samples without any special pretreatment. Under the optimum conditions of parameters, the recoveries of Cr(III) by analyzing the spiked water and soil samples were between 98.6 and 100.8 % and between 96.5 and 100.7 %, respectively. Detection limits of Cr(III) were between 1.4 and 3.6 ng?mL?1 for water samples and 5.6 ng?mg?1 for soil samples.  相似文献   
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