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81.
The process of deforestation in the Central Development Region (CDR) of Nepal is diverse in space and time, with rapid deforestation still occurring in areas outside the national parks and wildlife reserves. This paper identifies the spatial driving forces (SDFs) of deforestation in the CDR for 1975–2000 using satellite data of 1975 (MSS), 1990 (TM), and 2000 (ETM+) along with socio-demographic and socioeconomic variables. Radiometrically calibrated satellite images are individually classified into seven distinct classes and merged together to cover the entire CDR. Classification accuracies are also assessed. Areas of land use and cover within the areas of each Village Development Committee (VDC) and municipality represented by GIS polygons are calculated from the classified images by overlaying vector files of 1845 polygons representing sections of VDCs and municipalities in 30–1199 m, 1200–2399 m, 2400–4999 m and >5000 m elevation levels. These elevation levels were estimated from the DEM compiled from 24 ASTER scenes taken on different dates. Only the first three elevation levels are used in the analysis because area >5000 m is under permanent snow cover where human related forestry activities are almost negligible. A transition matrix is generated for 1975–1990 using classified images of 1975 and 1990 and then this product is used to further develop another transition matrix for 1990–2000 with the classified ETM+ 2000 images as the final stage. The GIS polygon layer is overlaid on the transition matrices to calculate deforestation areas for 1975–1990 and 1990–2000. Biophysical and socioeconomic information collected from various sources is then brought into a GIS platform for statistical analyses. Six linear regression models are estimated using SAS; in effect, two models for each elevation range representing the 1975–1990 and 1990–2000 periods of change to identify SDF influences on deforestation. These regression analyses reveal that deforestation in the CDR is related to multiple factors, such as farming population, genders of various ages, migration, elevation, road, distance from road to forest, meandering and erosion of river, and most importantly the conversion of forestland into farmland.  相似文献   
82.
Healthcare waste management (HCWM) options are inconsistent in Bangladesh. One of the first critical steps in the process of developing a reliable waste management plan requires a comprehensive understanding of the quantities and characteristics of the waste that needs to be managed. This study took into consideration both the quantity and quality of the generated waste to determine the generation rates and physical properties of healthcare waste (HCW) in Chittagong Medical College Hospital (CMCH) and also to estimate the amount of infectious and non-infectious waste generated in different wards. CMCH, the second largest hospital in Bangladesh, comprises 34 wards, 12 of which were selected randomly. Waste materials were collected from these wards and then segregated and weighed. Waste generation per day was found to be 73.22 kg/ward, 1.28 kg/bed and 0.57 kg/patient. A total of 2490 kg of HCW was produced each day in CMCH (37% being infectious and the rest being non-infectious waste). Infectious waste was 27.07 kg per ward, 0.47 kg per bed and 0.21 kg per patient and the non-infectious waste was 46.15 kg per ward, 0.81 kg per bed and 0.36 kg per patient per day. HCW comprised eight categories of waste materials with vegetable/food waste being the largest component (50.21%) and varied significantly (P < 0.05) among the 12 different wards studied. The greatest amount of HCW was recorded (154 kg) in Orthopaedics followed by 96.66 kg in the Medicine Unit-3 and the smallest amount was recorded in Casualty (8.79 kg). The amount of HCW was positively correlated with the number of occupied beds (rxy = 0.79, P < 0.01). There is no structured form of medical waste treatment in CMCH and most waste materials are dumped in open areas for natural degradation or re-sold by scavengers. It is essential to develop a national policy and implement a comprehensive action plan for HCWM that will provide environmentally sound technological measures to improve HCWM in Bangladesh.  相似文献   
83.
84.
Kinetic analysis of thermally activated phase transformations in drinking water treatment plant (DWTP) sludge suggests its applicability in the materials of construction. The suggested prediction has already been verified on the sludge-based bricks. The present study deals with incorporating the same sludge in the raw meal for the synthesis of Portland cement clinkers. For this purpose, two raw meals are prepared with varying sludge loadings. The sludge effect on reactivity of the crude mixture is evaluated on the basis of the free lime content sintered at various elevated temperatures. The results of chemical and mineralogical and scanning electron microscopic analyses reveal fine mineralogical contents of Portland clinkers calcined at 1450 and 1500 °C. Moreover, the cements prepared from these clinkers by the introduction of certain proportions of gypsum, depict significant durability. The obtained results elucidate that the studied DWTP sludge-incorporated Portland cement shows considerable potential to be commercialized.  相似文献   
85.
Environmental Science and Pollution Research - Cancer is a universal health issue, and many anticancer therapeutic drugs have been isolated from natural products. This study analyzed the cytotoxic...  相似文献   
86.
Although high concentrations of trace organic pollutants were recorded along the Egyptian Mediterranean Coast and its corresponding coastal wetlands, no published data are available for the levels of phenolic compounds. Thus, this work aimed to investigate the levels of phenolic compounds in sediments of a heavily polluted coastal wetland (Lake Maryut, Egypt). For that purpose, a method was optimized for the extraction and detection of chlorophenols, methylphenols, and nitrophenols in sediments using GC-MS. Sediments were extracted with 0.1 M NaOH/methanol by sonication. Cleanup of sediment extracts using liquid–liquid extraction and SPE was found important to remove most of the interfering co-extracts. The proposed analytical methodology was validated by analysis of matrix spikes. Detection limits were 0.063–0.694 μg/kg dw for sediments. Good recoveries (70–110%) and precision values (RSD?<?20%) were obtained from the fortification experiments at the parts per billion level in sediments. The method was applied to investigate the level of contamination with phenols in 19 sediment samples from Lake Maryut. Results revealed that higher concentrations were observed in the main basin (MB) of Lake Maryut affected by the discharge of effluents from a primary wastewater treatment plant, direct discharge of industrial effluents, domestic wastes, and agricultural effluents from Qalaa Drain (QD). Chlorophenols (CPs) were the major group detected in the lake sediments followed by methylphenols (MPs) and nitrophenols (NPs). CPs were dominated by 2-, 4-, and 3-chlorophenols. Concentrations of CPs were higher at the north and northwestern parts of the MB indicating the influence of industrial effluents discharged into the lake. On the other hand, higher concentrations of NPs were observed at the south and southwestern parts of the MB, which is subjected to the discharge of agricultural and domestic effluents via QD. Results of the risk assessment revealed that phenol, cresols, 2,4-dinitrophenol, 4-NP, 2-CP, 2,3,4,6-tetrachlorophenol and 2,4-dimethylphenol are contaminants of concern and that adverse ecological effects could possibly occur to benthic species from the exposure to these pollutants in Lake Maryut and thus phenols should be included in monitoring and pollution prevention programs in the Egyptian aquatic environment affected by anthropogenic activities.  相似文献   
87.
依靠大自然:尼日利亚北部的野生食品   总被引:2,自引:0,他引:2  
引言 在西非半干旱地区,当地农村社区都使用许多野生植物来补充其日常食品的不足,他(她)们的日常食品主要来自靠雨水浇灌种植出来的主食,比如小米、高粱、花生和豇豆等.  相似文献   
88.
Various and diverse industrial safety areas were identified and grouped as under: general areas of safety, Special areas of safety and industry specific areas of safety.

General areas of safety are common to all industries and special areas of safety are relevant only if the selected industry has such nature of work or hazard and whereas the industry specific areas of safety refers to process safety of the industry. Three separate modules were prepared along with contents.

For conduction of the programme, the selected industry must be studied and the designed safety education programme modules have to be adapted by leaving irrelevant areas in special and industry specific areas of the designed safety modules. The implementation of safety education programme was carried out at Bharath Heavy Electricals Ltd, Trichy and Southern Railway workshop, Trichy, by adapting the designed modules to suit these industries as mentioned above.

Effectiveness is measured by the increase in safety awareness of the selected industrial workers (sample), who had already undergone such programmes with short falls conducted within the industry itself. Research Tool was prepared based on the contents of the adapted safety education modules and pre-test and post-test were conducted, data collected and analysed.

The results were statistically significant as confirmed by t-test analyses.  相似文献   

89.
Regional Environmental Change - The soils of the Mediterranean Basin are the products of soil processes that have been governed by a unique convergence of highly differentiated natural and...  相似文献   
90.
Grabens are formed under the influence of extensional forces in a normal fault system. The Gulf of Gökova is an active graben located in SW Turkey. Active grabens such as the Gökova enclose highly faulted rocky coasts. Despite the existence of these rocky coasts, examination of google earth images, field studies, DEM analysis and previous studies in the Gulf of Gökova graben revealed that there could be different types of coasts in the region. In this study the factors causing the occurrence and potential environmental effects of the diverse coast types are evaluated. By using the Fairbridge (2004) coastal classification system, the coast types identified in the Gulf of Gökova graben can be classified as; A. Soft-less consolidated-erodible; A1: relatively Insoluble: detrital and loose beach, A2: soluble: beachrock and eolinite B. hard-cliffed-rocky, B1: longevity of hard-rock coast and B2: fault controlled cliffs. The percentages of these classes generally decreased from B1 (79%), A1 (12.4%), B2 (8.3%) and A2 (0.3%) in the study area. As a result of longshore currents, A1-type coasts usually develop as large plain adjacent streams and also in pocket beaches as narrow-long strips near rocky coasts. A2 type is observed in one location within the Gökova region, possibly due to local environmental conditions. However, B1 type developed in peridotites, cherty limestone and cliffs probably because of the active fault system and where the fault plane cut the coast, B2 type occurred. Possible threats to the Gökova region can be attributed to sea level rise owing to tectonism and global warming. It is anticipated that inundation, coastal erosion and salt water intrusion may also affect it.  相似文献   
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