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171.
Environmental Science and Pollution Research - The pervasiveness of microplastics in aquatic ecosystems has become a major environmental issue in recent years. The gradual dumping of plastic...  相似文献   
172.
This research had been conducted during year 2012 to review existing data on hospital waste management for some of Khartoum town hospitals and to try to produce appropriate proposals acceptable for waste management and final treatment methods. The overall status of hospital waste management in Khartoum has been assessed through direct visits and designated questionnaires. Eight main hospitals were covered in the study with an overall bed capacity of 2,978. The current waste management practice observed at all studied hospitals was that most of waste, office, general, food, construction debris, and hazardous chemical materials were all mixed together as they are generated, collected, and finally disposed of. Only a small portion of waste in some hospitals (part of potentially infectious, body parts, and sharps) are collected separately and treated in a central incinerator. The estimated value of per bed generation rate in the studied hospitals was found to be 0.87 kg/day, which lies within the range for the low-income countries. In all studied hospitals, it was found that workers were working under very poor unsafe conditions with very low salaries ($35 to $45 per month on average). About 90 % were completely illiterate or had very low education levels. At the national level, no laws considering hospital waste, or even hazardous waste, were found; only some federal general environmental regulations and some procedures from town and city localities for controlling general municipal waste exist. At the hospital level, no policies or rules were found, except in the radiotherapy center, where they manage radioactive wastes under the laws of the Sudanese Atomic Agency. Urgent actions are needed for the remediation and prevention of hazards associated with this type of waste.  相似文献   
173.
Rates of shoreline change along the coast of Bangladesh   总被引:1,自引:0,他引:1  
Bangladesh, at the confluence of the sediment-laden Ganges and Brahmaputra Rivers, supports an enormous and rapidly growing population (>140 million in 2011), across low-lying alluvial and delta plains that have accumulated over the past few thousand years. It has been identified as one of the most vulnerable places in the world to the impacts of climate change and sea-level rise. Although abundant sediment supply has resulted in accretion on some parts of the coast of Bangladesh, others are experiencing rapid erosion. We report a systematic assessment of rates of shoreline change over a 20-year period from 1989 to 2009, using Landsat satellite images with pixel resolution of 30 m on the ground. A Band ratio approach, using Band-5 divided by Band-2, discriminated the water line on images that were largely cloud-free, adequately registered, and at comparable tidal stages. Rates of shoreline change were calculated for >16,000 transects generated at 50 m intervals along the entire mainland coastline (>1,100 km) and major islands, using the End Point Rate (EPR) method in the Digital Shoreline Analysis System (DSAS) extension in ArcGIS®. Erosion characterises most of the seaward margin of the Sundarbans in western Bangladesh. Retreat rates of up to 20 m/yr are typical, with little evidence that local devastation of the mangrove fringe by Cyclone Sidr in November 2007 had resulted in uncharacteristic long-term rates of retreat where it made landfall. Erosion exceeded accretion in the Barguna Patuakhali coastal zone, most of which eroded at up to 20 m/yr, but with truncation of the southern tip of the Patharghata Upazila at up to 100 m/yr. In Bhola, erosion at rates of up to 120 m/yr were observed along much of the coast, but in the Noakhali Feni coastal zone, similar rates of erosion were balanced by rapid accretion of the main promontory by more than 600 m/yr. Rates of change were more subdued in the Chittagong and Cox’s Bazar coastal zones of southeast Bangladesh. Islands in the Meghna estuary were especially dynamic; Hatiya Island accreted along some of its shoreline by 50 km2 between 1989 and 2009, but lost 65 km2 through erosion elsewhere, resulting in the island moving south. Similar trends were observed on adjacent islands. The overall area changed relatively little across the entire coastline over the 20-year period with accretion of up to 315 km2, countered by erosion of about 307 km2.  相似文献   
174.
Palm oil production is one of the major industries in Malaysia and this country ranks one of the largest productions in the world. In Malaysia, the total production of crude palm oil in 2008 was 17,734,441 tonnes. However, the production of this amount of crude palm oil results in even larger amounts of palm oil mill effluent (POME). In the year 2008 alone, at least 44 million tonnes of POME was generated in Malaysia. Currently, the ponding system is the most common treatment method for POME but other processes such as aerobic and anaerobic digestion, physicochemical treatment and membrane filtration may also provide the palm oil industries with possible insights into the improvement of POME treatment processes. Generally, open ponding offers low capital and operating costs but this conventional method is becoming less attractive because the methane produced is wasted to the atmosphere and the system can not be certified for Carbon Emission Reduction trading. On the other hand, anaerobic digestion of POME provides the fastest payback of investment because the treatment enables biogas recovery for heat generation and treated effluent for land application. Lastly, it is proposed herewith that wastewater management based on the promotion of cleaner production and environmentally sound biotechnologies should be prioritized and included as a part of the POME management in Malaysia for attaining sustainable development. This paper thus discusses and compares state-of-the-art POME treatment methods as well as their individual performances.  相似文献   
175.
The objective of this study is to provide a perspective on the extremes of sea-level variability and predictability for the U.S.-Affiliated Pacific Islands (USAPI) on seasonal time-scales. Based on the Generalized Extreme Value (GEV) model, the L-moments method has been used to estimate the model parameters. The bootstrap method has been used to define the exceedance probability level of upper and lower bounds of the return periods at the 90% confidence interval. On the basis of these return calculations and expected extremes of high sea level, the seasonal maxima of sea level and the varying likelihood of extreme events have been estimated. For analyzing the predictability of the extremes of sea-level, a canonical correlation analysis (CCA) statistical model has been developed. Findings reveal that there is seasonal climatology of extreme events in the vicinity of USAPI that are variable on temporal and spatial scales. Some of the islands (Yap and Saipan) display considerably higher seasonal extremes than the others for 20 to 100 year return periods because of typhoon-related storm surges. These surges are likely to cause huge tidal large sea-level inundations and increased erosion to low-lying atolls/islands and result in considerable damage to roads, harbors, unstable sandy beaches, and other major infrastructures. Finally, the need for evaluating the extreme events and associated typhoons from a regional perspective has been stressed for coastal hazard management decision analyses in the USAPI.  相似文献   
176.
Environmental Fluid Mechanics - Buoyant turbulent plumes are often categorized by their geometry and described as either round plumes, issuing from a point source, or line/planar plumes, issuing...  相似文献   
177.
Environmental Science and Pollution Research - The water quality index is one of the prominent general indicators to assess and classify surface water quality, which plays a critical role in river...  相似文献   
178.
Environmental Science and Pollution Research - The study’s goal is to investigate the impact of foreign direct investment (FDI), tourism, electricity consumption, and economic development on...  相似文献   
179.
Environmental Science and Pollution Research - Adolescent females are often environmentally exposed to pesticides by living near agricultural fields, by using pesticides at home, or by having...  相似文献   
180.
Environmental Science and Pollution Research - Several studies have reported the toxicological implications of exposure to petroleum hydrocarbon fumes in animal models. There is little...  相似文献   
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