Journal of Environmental Studies
Year:2012 | Volume:37 | Issue:60|Papers Count:18

An increase in energy prices will reduce environmental emissions via two channels. This policy will decrease the fossil fuel consumption and hence will cause emission reductio n. On the other hand, the cost-push will encourage technology improvement for firms and households. These changes in fossil fuel demand and energy use technology will affect the emission level.It is estimated that phasing out fossil fuel subsidies by 2020, will cut the expected growth in carbondioxide emissions by 2 gigatons. Herein, Iran stands in 10th grade by annual CO2 emission in the world and 1st in the MENA. Along with G-20 leaders commitment to “rationalize and phase out inefficient fossil fuel subsidies that encourage wasteful consumption”, Iran is also taking a key step toward reforming energy subsidies and increasing the prices. In early 2010, a law outlining far-reaching subsidy reform was enacted in Iran and is started by December 2010. The subsidy reform law calls for gradual implementation of market-based energy pricing and the replacement of subsidies by targeted assistance to lower income groups.

Problems of environmental degradation that sources in economic activities of man are of crucial worldwide issues. All societies are more or less confronted to these problems and are concerned about their outcomes. Its importance is not only from natural resources aspects, but also from the socioeconomic point of view. Degradation occurs when Earth's natural resources- that is, water, air, and soilare depleted. Degradation also impacts wildlife, plants, animals, and micro-orgasms. Environmental changes and degradations are derived from and are based on many interrelated factors including urbanization, population and economic growth, intensification of agriculture, increase in energy use, and increase in transportation. For example, when trees in forests are cut down in large quantities, so that more homes can be built to dwell the augmented population, the earth is being destroyed. Trees that absorbed carbon dioxide to help the biosphere are now unable to do so. The rapid pace of urbanization and industrialization that is translated in more energy consumption, may lead to serious environmental concerns. Over the past century, natural resources have depleted remarkably resulting from accelerated pace of economic and social transformation all over the world.

Although individuals knowledge and awareness toward natural resources, especially wetlands have recently been increased, optimal consideration toward wetland’s importance, functions and sensitivity are still insufficient. Valuating non-commercial functions of environments like wetlands is important for a number of reasons such as preventing natural resources from being destroyed or overused. Also, enjoying knowledge and understanding about the environmental benefits, clarification of environmental problems of the country and offering them to the country's planners for suitable decision making, measuring the role and importance of environmental resources in supporting humanistic welfare and sustainable development, preventing many of environment–threatening activities, adjusting and correcting national accounts such as gross national product and preventing the destruction and irregular use of natural resources are other reasons for environmental efficiency valuation.

Generally, the word ‘structure’, in forest ecosystem refers to the spatial arrangement of tree’s characteristics (i.e. age, dimension, species, sexuality etc.). Nowadays, studying forest stands spatial structures is extensively used for determining habitat and species diversity. For sustainable forest management, describing stand structure before applying silvicultural and utilization practices, as well as investigation of induced changes as a result of management activities are essential. Commonly, according to Kint et al. (2000), forest spatial structure can be considered at three different levels:1). Positioning or contagion; indicates the spatial distribution of trees under special pattern such as: regular, random, cluster or mixed features of the mentioned patterns;2). Mixture; investigates spatial arrangement of different tree species.

Energy consumption in industry is associated with environmental damages. Steel industry is one of the most energy-consuming industries in the world, which is related to melting furnace resulted in environmental pollution. To reduce these pollutions in different systems, venturi scrubber and electrostatic precipitator (ESP) dust collectors can be applied into different systems. Electrostatic precipitator dust collector separates dusts by using electrostatic forces. Venturi Scrubber dust collector separates dusts by using water spray. Electrostatic precipitator and Venturi Scrubber are used in cement, gypsum, steel and power industry. One of the causes of global warming is the energy consumed by dust collectors installed all over the world.

Principles of Sustainable development have been considered in three dimensions: social, economic and environmental. Problems such as high level of population increase, high level of resources consumption and population concentration in urban areas, make the achievement of sustainable future more difficult.Currently, more than 50% of population live in urban areas, and by 2020, this number will reach to 60%.The role of cities in achieving sustainable development is quite important, since large cities are the consumers of natural resources. In fact they are the producers of pollution sources, and the place of human activities concentration. Thus, urban management is an important issue.One of the controversial issues is urban sprawl. There are numerous definitions of urban sprawl. In summary, urban sprawl has been defined as unplanned sprawl, uncontrolled expansion, mono-functional land use, low density and discontinuous land use. Some of the consequences of urban sprawl are occupying green spaces around cities, high costs of infrastructure, high level of energy use, social segregation, car dependency, traffic increase, pollution, temperature increase and decrease in air and water quality.

Tourism as one of the greatest and the most adhering commercial activities in the world has a tendency to ecotourism in recent decades. The objectives of ecotourism or ecological tourism cannot be achieved without the protection of environment, observing the local inhabitants, their rights and characteristics as hosts, all of which should be considered in this paper.

Landscape and land uses are rapidly changing in different areas due to urbanization growing and population increasing. There are several economic, social and environmental consequences for this phenomenon. Urbanization expanding and increasing of construction by human cause underlying changes in ecology and function of landscape structure and spatial pattern causes gradual changes in landscape.Now spatial analysis and structural characteristics are important issues in patches formed according to interpretation and modeling of landscape changes in space-time. Development studies, such as remote sensing, geographic information systems and landscape ecology, are increasing Inattention to environmental considerations and attitudes in land management planning and simplified patterns of nature finally causes serious damages to the natural systems. The management principle says "what cannot be quantitative is not manageable". In recent years, a lot of effort has been done in order to quantify appropriate development methods and processes.

Development of urban green spaces and rational distribution of neighborhoods, especially in city centers, in a way that fits urban construction is considered as one of the major challenges of contemporary metropolises. Since open and green spaces in urban areas often seem to lack direct economic values, expanding the manufacturing of precaution instruments in short term produces higher profits in local government investment. Thus, public sector will have to increase land uses in the short term economic interests, and financial support for the development of urban green spaces is less in comparison with other investments. This problem exists in both developed and developing countries, especially in city centers.However, in developing countries, due to urban management of short term economic interests, the presence of the problem is highlighted more.Obligations of developed countries to environmental agreements and the pressure of public opinion seem to have more conscious of environmental issues that have created an incentive to identify new solutions towards the development of urban green spaces. On the other hand, the private sector developers in the construction sector to reduce costs and gain more profit in making buildings, the percentage of which dedicated to green spaces in different ways is added to the whole infrastructure. This content in zones with high density class (both in terms of building and in terms of traffic volume) is featured in the construction of residential buildings with parks and green natural landscape in large scale with the rapid development of large cities seems impossible.

The Caspian Sea is facing severe oil pollution due to exploitation and transportation of oil. Although currently there is no oil extraction along the Iranian coasts of the Caspian Sea, however, during the last two decades Iran has been importing processed oil productions through the sea. Therefore, the coastal areas adjacent to the importing ports were exposed to oil pollution caused by accidental leakage of oil at oil terminals or illegal discharges of oil wastes from different types of vessels.Anzali Port is the oldest port of Iran in the Caspian Sea which is located at the western part of the southern coast of the Caspian. The Port has always been very active with a large amount of shipping.Anzali port connects the Anzali Wetland to the Caspian Sea and consists of two rubble mound breakwaters which constitute the basin of the port.

Surfactants are amphiphilic molecules consist of a hydrophilic head and a hydrophobic tail. They are the active ingredients found in soaps and detergents with the ability to concentrate at the air-water interface and are commonly used to separate oily materials from a particular media. Surfactants increase the aqueous solubility of non-aqueous phase liquids (NAPLs) by reducing their surface and interfacial tension at air-water and water-oil interfaces. As the interfacial tension is reduced and the aqueous surfactant concentration increased, the monomers aggregate to form micelles. The concentration at which micelles first begin to form is known as the critical micelle concentration (CMC). This concentration corresponds to the point where the surfactant first shows the lowest surface tension. Many physical properties used to characterize surfactants, depend on the CMC such as: emulsion formation, oil solubility, foaming and detergency, interfacial and surficial tensions. These properties may be used to assess surfactant suitability for environmental remediation works such as soil washing.

Dyes, as they are intensively colored, cause special problems in effluent discharge, and their effects are both aesthetically displeasing and hazardous. They can prevent sunlight penetration, decreasing photosynthetic activity in aquatic environments. Some azo dyes that cause effluent to be colored have been implicated as being mutagenic/carcinogenic as well as toxic to aquatic life. Thus, it is necessary to eliminate dye from wastewater before it is discharged.

In water treatment processes, because of complicated and nonlinear relationships between a number of physical, chemical and operational parameters, using analytical models with the ability to capture underlying relationships using examples of the desired input-output mapping is quite suitable. Artificial Neural Networks (ANN) has been increasingly applied in the area of environmental and water resources engineering. The main advantage of Artificial Neural Networks over physical-based models is that they are data-driven.

The Contamination of environment by toxic elements is a worldwide problem, since these elements are indestructible and most of them have toxic effects on living organisms, when they exceed a certain concentration. Sediments, as the largest resources of heavy metals, play a rather important role in the transformation of toxic elements.

Nowadays, diseases caused by water pollution are one of the main reasons of death. Currently, in most southern cities of Iran, water treatment at home has become a popular culture. Activated carbon is the original material in such water treatment filtrations. Widespread use of activated carbon increases the cost of treatment. Absorption isotherms of the present model are used for the modified mass balance for each time constant. In this research, Rafsanjan Pistachio shell as a local and inexpensive adsorbent to remove nickel from aqueous solution is introduced. Also, the impact of changing the adsorbent mass on balance time and the absorption efficiency will be investigated. In addition, Ni uptake kinetics parameters of the models are to be determined and introduced.