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121.
In the last three decades, the industrial and human activities in the coastal area of Saudi Arabia have increased dramatically and resulted in the continuous invasion of different types of pollutants including heavy metals. Seven sediment cores were collected from three major industrialized areas; Jeddah, Rabigh and Yanbu, along the coast of Saudi Arabia to determine the spatial and temporal distribution of metals and to assess the magnitude of pollution and their potential biological effects. Sediments were analyzed for texture, calcium carbonate contents, organic matter and metals (Al, Fe, Mn, Cd, Cr, Cu, Ni, Pb and Zn). Some metals like, Cr, Mn, Ni and Zn, were enriched in the upper 15 cm of core samples (recent deposition of sediments). Cadmium concentrations showed high fluctuations with depth and reverse pattern to that for Al, Fe and Mn which indicated land based sources of this element to the studied areas. Elevated concentrations of lead were recorded in the bottom layers of cores in Jeddah that indicated the most dramatic increase in usage of gasoline in early 1970s. The calculated contamination factors (CF's) were found in the following sequences: Cd > Pb > Ni > Cu > Zn > Cr > Mn for all studied areas. Results of Pollution Load Index (PLI) revealed that Jeddah is the most polluted area, followed by Rabigh while Yanbu is the least contaminated area. Except for Ni, the concentrations of most metals in the majority of sediment samples were believed to be safe for living organisms. As no data were available on the concentration of metals in core sediments in the coastal area of Saudi Arabia, the results of this study would serve as a baseline against which future anthropogenic effects can be assessed.  相似文献   
122.
Many drainage schemes and salinity control projects have been executed world wide. Pipe drainage has widely been used in Pakistan, Egypt and India to control waterlogging. The impact of pipe drainage on land and water was evaluated in this paper using data of three pipe drainage projects in Pakistan namely Khushab Salinity Control and Reclamation Project, Fourth Drainage Project in Faisalabad and Swabi Salinity Control and Reclamation Project. Data by regular monitoring of these projects were collected. The effect of pipe drainage on water table depth at these three locations has been compared. Water quality and soil salinity improvement due to the pipe drainage has also been investigated. Data, related to water table depths and discharges from drain pipes/wells, was collected. Observation wells, installed at various places by the Water and Power Development Authority, were used for collection of this data. To evaluate the impact of the projects on salinity, soil samples from all the three locations were tested. A questionnaire was prepared to get the view of the people about the projects. It was revealed that in these areas, due to subsurface pipe drainage, the percentage of the abandoned land has been considerably decreased. Over drainage was observed in a few places of the projects. The farmers at such places were asked to change their cropping patterns. Ultimately, there has been an increase in area under cultivation, crop yields and cropping intensity in the projects’ area.  相似文献   
123.
Physico-chemical groundwater (GW) parameters were evaluated to understand the hydrogeochemical processes in the Siwalik plains of Jammu and Kashmir, India. During the 2012–2013 post-monsoon (POM) and pre-monsoon (PRM) seasons, GW samples (n = 207) from deep bore wells and shallow open wells were chemically analysed. Cations (Ca2+, Mg2+, Na+, K+ and Fe2+) and anions (HCO3 ?, Cl?, SO4 2? and F?) showed a wide spatio-temporal variation. Results suggest that weathering and dissolution of carbonates and silicate rocks is the main source of water mineralization. The major hydrochemical facies is characterized by Ca-Mg-HCO3 and Ca-HCO3 during the PRM and POM seasons respectively. The presence of sulphate-bearing water in a large number of the samples indicates a significant role of gypsum dissolution and anthropogenic contamination of the GW. Factor analysis (FA) and hierarchical cluster analysis (HCA) revealed that the variability of hydrochemistry is mainly related to rock-water interaction, dissolution of carbonates and other lithological units as well as the influence of anthropogenic activities in the area. Overall, it was found that the GW quality is within the limits of human consumption. The higher concentration of a few chemicals indicates an increasing trend of industrial contamination of the GW. For sustainable development of the portable GW in Siwaliks, it is necessary to minimize the adverse impacts of the anthropogenic and industrial contamination on the GW resources through best management practices and prevent its further contamination to a level that could make GW unsuitable for human uses.  相似文献   
124.
The present study was undertaken to examine the drinking water quality of Rawal Treatment Plant, Rawalpindi and its distribution network by collecting samples from eight different locations. The aim was to determine potential relationship between the presence of microorganisms and chlorine residual in the distribution network. Quantification of chlorine residual, turbidity, standard plate count (SPC), fecal and total coliforms by Most Probable Number (MPN) was performed. Three different forms of chlorine were measured at each sampling station such as free chlorine, residual chlorine, chloramines and total chlorine residual. A critical evaluation of data presented indicated that pH generally ranged from 7.02–7.30; turbidity varied from 0.34–2.79 NTU; conductivity fluctuated from 359–374 μS/cm; and TDS values were found to be ranging between 180–187 mg/l. Station # 7 was found to be most contaminated. The value of total chlorine was found to be 0.86 to1.7 mg/l at Station # 3 and 6, respectively. Highest standard plate count was 62 CFU/ml at Station # 7. Total coliforms were less than 1.1 MPN/100 ml at almost most of the stations except at Station # 3 where it was found to be greater than 23.0 MPN /100 ml. Overall aim of this study is to create awareness about contamination of drinking water in the water distribution networks and to make recommendations to provincial agencies such as EPA, CDA and WASA that regular monitoring should be carried out to ensure that the chlorine residual is available at consumer end.  相似文献   
125.
126.
根据乌鲁木齐市的经济社会和城市规划建设现状,研究与构建乌鲁木齐城市生态框架,整治城市环境污染,提高环境质量,健全气流通道,协调水利,并通过绿色通道及“绿楔”、“绿脉”形成通畅的气流,恢复城市外部范围生物的正常输入和市中心区生物基因的自然调节使城市动植物群落之间相适宜,把乌鲁木齐市建成空气清新、景观秀丽、环境宜人的生态城市。  相似文献   
127.
This review provides an innovative approach of treating palm oil mill effluent (POME) from open pond and closed anaerobic sludge reactor for generation of green energy in the form of biogas containing methane. Improper techniques for the treatment and management of POME produce hazards to people and contribute to global warming. In all over the world, the total crude oil palm production in the countries like Malaysia, Indonesia, Africa, Latin America, Asian countries, Solomons and other were around 51, 31, 7, 6, 3, 2 and 1% compared with soya 41.8% and coconut 3.48%, respectively. In the year 2014–15, Malaysia generated at least 87.8 million tonnes of palm effluent per year. Various studies reveal that about 80% of palm effluent is disposed off partially treated in open dumps. The generated certified emission reductions (CERs) estimated and favoured the treatment of POME in anaerobic reactor by replacing open lagoon of aerobic system for cleaner production. The clean development mechanism (CDM) encourages the utilisation of upflow anaerobic sludge blanket reactors for POME treatment and methane capture to earn CER credits as a source of revenue.  相似文献   
128.
Environment, Development and Sustainability - In the current study, we investigate the dynamic association of tourism, renewable energy, income, foreign direct investment (FDI), and carbon dioxide...  相似文献   
129.
Environmental Economics and Policy Studies - This paper examines the relationship between institutional pressure of national carbon pricing policy and the voluntary environmental disclosures (VED)...  相似文献   
130.
Journal of Polymers and the Environment - Nanocomposite membranes promoted by mimic enzyme was developed and optimized for biogas upgrading at moderately high pressure applications up to...  相似文献   
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