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Prioritization of Environmental Sensitive Spots in Studies of Environmental Impact Assessment to Select the Preferred Option, Based on AHP and GIS Compound in the Gas Pipeline Project
2019
Padash, A. | Ataee, S.
Environmental assessments are essential in order to align the process of country's progress towards sustainable development. It is important for the project to be implemented in direction of sustainable development, which is to carry out a project in such a way that in both short and long term, the greatest advantages and the least harm are inflicted on the environment, economy, communities, and culture. Environmental assessment of gas pipelines is classified as a linear projects; therefore, the design and implementation of an appropriate method in accordance with the project's linearity, due to the use of GIS tools and multi-criteria decision-making methods, can be a good innovation for this study, in comparison to previous similar projects. The purpose of this study is to identify the best option for gas pipelines. Once the project's study scope is specified, the study based the sensitive environmental parameters of the area (based on the requirements of environmental impact assessment reports) on two methods of Analyzing Hierarchical Process (AHP) and overlaying methods for sub-parameters, ranking and prioritizing the area of evaluation. Based on the results, the first and second priorities belong to the parameter of distance and position in the protected areas with a weight of 29.9% and hydrology with a weight of 24.7%, followed by slope, vegetation, land use, and fault, which are ranked third to seventh, respectively. After identifying the best map option, the study extracts the critical points for the construction of pipelines, identifies the negative effects of the project, and presents the environmental impacts and preventive measures, reduction and compensation of negative effects in both construction and operation phases, along with a summary of the Environmental Management Program (EMP).
显示更多 [+] 显示较少 [-]Remediation of Lead-Contaminated Soil, Using Clean Energy in Combination with Electro-Kinetic Methods
2019
Hussein, A. A. | Alatabe, M. J. A.
The present study aims at investigating the feasibility of using solar energy as a power source to run electro-kinetic remediation in order to clean-up lead from three types of Iraqi soil. In order to do so, it carries out six tests with enhancement conditions, involving pH control and injection wells. Conducted in the city of Baghdad, Iraq, the experiment, is divided into two groups so that the effect of applying continuous and constant voltage from solar panels study, by means of charge control and battery along with non-continuous and non-constant DC voltage from solar panel could be studied. The DC voltage has been generated by two Solar panels, each with a maximum voltage of 17 volts. All experiments have commenced in March 2017, wherein the soil has been contaminated with a concentration of Pb, equal to 1500 mg/kg as well as initial moisture content equal to 30%. The remediation lasts for seven days, with a potential gradient of about 1.2 V/cm. At the end, the experimental results show that the overall removal efficiencies of 90.7%, 63.3%, and 42.8% have been achieved for sandy, sandy loam, and silty loam soils, respectively, when using solar panels with charge control and battery.
显示更多 [+] 显示较少 [-]Assessment of Pb and Ni contamination in the topsoil of ring roads' green spaces in the city of Hamadan
2018
Sobhan Ardakani, Soheil
Due to rapid industrialization and urbanization, environmental pollution has become a major concern in developing countries; therefore, the main objective of the current study is to determine heavy metal contents of Pb, and Ni for 42 topsoil samples, collected from 14 green spaces along the 1st and 2nd ring roads in Hamedan City in 2016. For this purpose, after determining some chemical properties as well as acid digestion of soil samples, Pb and Ni concentrations have been found in the soil samples with ICP-OES. All statistical analyses have been conducted, using SPSS 18.0 statistical package, with the results showing that the metal levels in soil samples, collected from green space of 1st and 2nd ring road, have been 34.86±10.28 and 41.57±10.08 mg/kg for Pb and 14.0-20.33 and 14.0-20.0 mg/kgfor Ni, respectively. Also the mean concentration of Pb and Ni have been lower than MPL. According to heavy metal concentration maps, the spatial distribution patterns of Pb, and Ni contents in the soil samples are generally similar along the 1st and 2nd ring road. Due to the fact that traffic volume in the 2nd ring was higher than the 1st one, there has been a significant difference in the mean contents of Pb between the topsoil samples, collected from the 1st and 2nd ring roads; therefore, it is recommended to keep environmental health in order to control the anthropogenic sources, causing the pollutants discharge into the environment is recommended.
显示更多 [+] 显示较少 [-]Arsenic Health Risk Assessment through Groundwater Drinking (Case Study: Qaleeh Shahin Agricultural Region, Kermanshah Province, Iran)
2018
Sobhanardakani, Soheil
Groundwater resources make up an important portion of potable and irrigation water in Iran, making it important to monitor toxic elements of pollutants in these resources in order to protect the inhabitants' health. The current study has been carried out to assess the health risks, caused by trivalent inorganic arsenic-polluted groundwater in Qaleeh Shahin Plain, an important agricultural region in Kermanshah Province. For this purpose, in total 20 groundwater wells have been chosen randomly. The samples have been filtered (0.45 μm) and preserved with HNO3 to a pH level lower than 2, then to be taken in acid-washed polyethylene bottles and kept at a temperature of 4 °C for further analysis. Finally, As(III) concentration has been determined, using ICP-OES with three replications. Results have shown that mean content of As (ppb) in groundwater samples were 6.0 ± 3.0 for winter and 9.0 ± 6.0 for summer in 2014. Also, according to the results, the computed values of the hazard quotient (HQ) and target risk (TR) of groundwater samples were below 1 and less than 10E-06, respectively; therefore, non-carcinogenic effect (chronic risk) and carcinogenic exposure are not likely for the inhabitants of this study area. However, due to over and long-term use of agricultural inputs in the study area, it is recommended to have some paramount consideration for better management and care of using agricultural inputs, especially chemical fertilizers, arsenical pesticides, or herbicides, and for treatment of As-polluted groundwater with proper removal methods prior to preparation of drinking water.
显示更多 [+] 显示较少 [-]A Review of on Environmental Pollution Bioindicators
2018
Asif, Nayyab | Malik, Muhammad | Chaudhry, F.N.
Qualitative status of the environment is signaled by a group of indicators, known as bioindicators, several of which are responsible for showing progressive impacts of different types of pollutants. Having addressed the influence of various bioindicators in environmental pollution, it has been revealed that bioindicators are sensitive to any disturbance in any environment. With regards to the pollution, the quality of an ecosystem can be judged by an organism, which is actually an indicator and play a key role in monitoring its changes. A reliable and cost effective way to evaluate the changes in the environment is possible by means of indicator species as ecological indicators, yet selecting a specific indicator poses a real challenge, followed by its identification as well as relation among indicators and their particular applications. As a result, environmental, ecological, and biodiversity indicators fulfill their goal of monitoring environmental quality. The current situation requires cost effective bioindicators along with their reliability to detect and mitigate the impacts of pollution in our environment.
显示更多 [+] 显示较少 [-]Review of Heavy Metal Accumulation in Aquatic Environment of Northern East Mediterrenean Sea Part II: Some Non-Essential Metals
2018
Yilmaz, Ayşe | Yanar, Alper | Alkan, Ela
Heavy metals that enter marine environment and remain in the water as well as the sediments are accumulated by aquatic organisms, thus becoming highly good indicators to monitor metal accumulation in the long run. Metals are potentially harmful to humans and most organisms at varied levels of exposure and absorption. Northern East Mediterranean Sea is a crucial region as it is an area, shared by numerous aquatic species with pollutant factors such as heavy marine traffic, transportation ports, industry plants, iron and steel works, oil pipeline installation, and other small factories. While the previous part of this review (Review of heavy metal accumulation on aquatic environment in Northern East Mediterranean Sea part I: some essential metals) evaluated the data from previous studies concerning toxic effects of selected essential metals on seawater, sediment, and different tissues of aquatic animals, collected from different areas in Northern East Mediterrenean Sea since the 1990s, the present part intends to evaluate the data from previous studies on toxic effects of selected non-essential metals. For this purpose, 94 articles and 6 theses have been examined and a good deal of information has been gathered to open a forward-looking view of the studied area’s pollution. Althought there has not been any harmonization, when comparing heavy metals investigations in the bay, all studies have shown that consumption of aquatic species from the region causes no problem to human health.
显示更多 [+] 显示较少 [-]Environmental Management of Oil Pipelines Risks in the Wetland Areas by Delphi and MCDM Techniques: Case of Shadegan International Wetland, Iran
2018
Golbarg, Farhad | Nabi Bidhendi, Gholamreza | Hoveidi, H
The aim of this study is to assess the risk factors of pipelines and prioritize their severity in order to prevent their effects in Shadegan International wetland, Iran. Due to the participatory nature of the managerial affairs, the study employs an integrated approach that combines Analytic Hierarchy Process (AHP) and Delphi Method. Also, Likret Scale has been applied to quantify the qualitative (verbal) data, thus reducing the uncertainty of oil pipelines' risk evaluation. In order to evaluate potential risk factors, Failure Mode Effects Analysis (FMEA) method has been applied. According to the study results, in terms of the likelihood of environmental impacts on the main considered criteria of natural and man-made environments, the former's effect is a priority risk, weighing 0.670 and primarily important. On the other hand, environmental hazards caused by oil pipes of water quality in Shadegan wetland has been ranked first, with a relative weight of 0.389 to contain the highest level of risk. The risk degree for diversity and density of benthos is 12.6 and 6.3for fish, both higher than other parameters of water systems in Shadegan wetland. Considering the recognized factors that lead to probable risks of pipelines along with their most notable outcomes, the paper suggests environmental management plans on how to control and reduce the potential impacts, with an emphasis on elimination of the most likely causes.
显示更多 [+] 显示较少 [-]Increasing Level of Ammonia in the Surface Raw Water Source at Dhaka, Bangladesh
2018
M., Serajuddin | Chowdhury, Aktarul | Hussain, M.M.
In 2004,ammonia concentration in raw water of Sitalakhya River at the eastern periphery of Dhaka was found higher than the expected rate of 4 mg/Lforecasted in feasibility studies,with a value of about 8 mg/L, which could not be removed by conventional treatment chain employed at Dhaka, hence, recentlyan ammonia removal plant has been constructed. This important background has ledto the current study on ammonia, a single quality parameter to understand the trend of deterioration, its probable causes, and the probable remedy.Water samples have been collected and tested for ammonia for a period of fifteen years, from 2002 to 2017, mostly in the laboratory of the existing plant. Ammonia levels have been found generally below 4 mg NH4-N/L in the wet season,though during the dry season they rise up to 20 mg NH4-N/L (sometimes more). The maximum and average values of concentration follow a more or less similar pattern with time, withboth average and maximum values, increasing around 1 mg/L annually,suggesting a similar trend in future which will make the existing treatment process inadequate. This needs attention in terms of both regulatory measures and proactive strategies on how to handle the resulting future challenges.
显示更多 [+] 显示较少 [-]Analysis of the Stringency of Drinking Water Quality Standards of Bangladesh in Comparison to the USA, EU, Japanese, and Indian Standards
2018
Islam, Kamrul | Zahra, Fatima-Tuz- | Chowdhury, Md. Arif | Biswas, Suvo Moy
Water is one of the most crucial substances for life. In order to maintain their public health, each and every country has defined standards of drinking water quality, beyond which the water is considered harmful for human health. The current study compares physical, chemical, and biological standards of drinking water quality for the USA, EU, Japan, India, and Bangladesh, considering 4 physical parameters (namely, color, odor, taste, and turbidity), 35 chemical parameters (such as Calcium (Ca), Magnesium (Mg), Phosphate (PO43-), Sodium (Na), Phenolic compounds, Nitrite (NO2-), Arsenic (As), Aluminum (Al), etc.) and 2 biological parameters (i.e., Coliform (Fecal) and Coliform (Total)). The data has been collected from several secondary sources and since processes of data collection for water quality differ from one another, this aspect has been ignored. No variation has been found in biological water quality standards along with physical quality standards of the considered regions. In order to find out the differences in chemical parameters, standard ANOVA and pair-wise F-test have been conducted. There was no disparity among chemical parameters in ANOVA test. Moreover, thanks to the few excessive values of the standards (as in case of Bangladesh), the COD value is 4 mg/L, whereas in other countries this parameter is much less. However, the chemical parameters of water quality standards in Bangladesh vary significantly from other countries. Besides, there has been no variation among the standards of other countries, even though they are located in different continents. Most interestingly, despite being neighbors, Bangladesh and India differ significantly in this regard.
显示更多 [+] 显示较少 [-]Acoustic Environment in the Bus: an Empirical Study
2018
Swain, Bijay | Goswami, Shreerup
Traffic snarl-up or traffic jam is a common phenomenon in Puri, one of the imperative pilgrimage sites for Hindus as well as a popular tourist destination in India. Traffic congestion inevitably produces traffic noise, in turn annoying the drivers, leading to road rage. Keeping this in mind, the present article has monitored and assessed different noise descriptors in 7 different types of buses, totally involving 35 buses in and around Puri, for three years, from 2014 to 2016. The minimum and maximum noise levels have been more than 65.3 dB and 90 dB, respectively. Also, Leq is beyond 80dB, demonstrating a noisy environment inside the bus. The result of Karl Pearson’s Correlation Co-efficient clearly indicates that in general, the noise levels have gradually increased from 2014 to 2016. Furthermore, it has conducted a survey to reveal opinions of 156 passengers and 50 drivers of the buses concerning their annoyance from noise pollution.
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