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31.
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Environmental quality for environmental health has been examined visually by describing general conditions and drinking water supply, sanitation and solid waste treatment conditions and practices in six South-East Asian villages with a dense population. The environmental review was supplemented by discussions with local people and political and administrative decision makers. Some drinking water analyses were done in order to show the water quality to the local people. The quality of the general conditions and the conditions and practices of drinking water supply, excreta disposal and solid waste treatment practices have been graded with the grading system presented below. The grading could be done in 1 or 2 days in each area by two persons, of which one was an environmental scientist and the other a social scientist, who also knew the local culture and worked as a translator.  相似文献   
33.
用蚕豆根尖细胞微核技术检测乌鲁木齐河水质   总被引:2,自引:0,他引:2  
应用蚕豆根尖细胞微核技术对乌鲁木齐水质进行检测,测定各样点水样诱导的蚕豆根尖微核千分率及综合污染指数,并进行F检验,结果表明,各样点MCN‰有显著性差异,20个样点中有11个样点 的综合污染指数大于2,4个样点水样的综合污染指数大于3.5,和对照组相比有显著差异。所获得数据表明乌鲁木齐河水质受到较为了严重的致突变性污染。  相似文献   
34.
Madhupur National Park is renowned for severe resource ownership conflicts between ethnic communities and government authorities in Bangladesh. In this study, we applied the Institutional Analysis and Development framework to identify: (i) past and present informal institutional structures within the ethnic Garo community for land resource management; (ii) the origin of the land ownership dispute; (iii) interaction mechanisms between formal and informal institutions; and (iv) change in land management authority and informal governance structures. We identify that the informal institutions of the traditional community have undergone radical change due to government interventions with implications for the regulation of land use, informal institutional functions, and joint-decision-making. Importantly, the government’s persistent denial of the role of existing informal institutions is widening the gap between government and community actors, and driving land ownership conflicts in a cyclic way with associated natural resource degradation.  相似文献   
35.
Malaria continues to be a public health problem in Bangladesh, despite efforts in the 1960s to eradicate the vectors through the use of DDT. At one point, eradication of malaria was acclaimed but later on it reappeared. The use of DDT is no more legally allowed in Bangladesh, which has been officially replaced by a number organophosphates and/or synthetic pyrethroids and their combinations in addition to the integrated vector management (IVM) package. IVM being a community approach is still to go a long way to be mass popular. Adulticides, larvicides, residual sprays, mosquito coil, insecticide-impregnated curtain, aerosol, etc. still serve as the major weapons of mosquito control. Thus, mosquito control still mostly depends on chemical insecticides. Although the use of DDT is banned in Bangladesh, there are reports on its illegal use in different forms. Moreover, there is tons of leftover DDT in Bangladesh, which is likely to cause several diseases. As per one report, about 500 MTs of DDT stockpiles are lying in the Medical Sub-Depots at Chittagong for over a period of 26 years. DDT is a persistent organic pollutant pesticide, which can cause diseases like cancer, endocrine disorder, disruption of immune system, embryonic abnormality, reproductive disorder, etc. Other chemical insecticides, which are replacing DDT, are also not free of hazardous impacts. IVM thus appears to be a wise approach requiring concerted efforts for the management of mosquito to control malaria. Such an IVM comprises use of Bacillus thuringiensis Berliner var. israelensis, methoprene, biocontrol agents, cleaning of breeding sites, pyrethroid-impregnated curtain, etc. Therefore, a wise effort should be adopted to completely stop the use of DDT, eliminate its stockpiles wherever they are in Bangladesh and to popularise the IVM, not the chemicals-based alternatives throughout the country.  相似文献   
36.
This study investigated the removal of parabens, N,N-diethyl-m-toluamide (DEET), and phthalates by ozonation. The second-order rate constants for the reaction between selected compounds with ozone at pH 7 were of (2.2 +/-0.2) X 10(6) to (2.9 +/-0.3) X 10(6) M 1/s for parabens, (2.1+/- 0.3) to (3.9 +/-0.5) M-1/s for phthalates, and (5.2 +/-0.3) M-1/s for DEET. The rate constants for the reaction between selected compounds with hydroxyl radical ranged from (2.49 +/-0.06) x 10(9) to (8.5 +/-0.2) x 10(9) M-1/s. Ozonation of selected compounds in secondary wastewater and surface waters revealed that ozone dose of 1 and 3 mg/L yielded greater than 99% depletion of parabens and greater than 92% DEET and phthalates, respectively. In addition, parabens were found to transform almost exclusively through the reaction with ozone, while DEET and phthalates were transformed almost entirely by hydroxyl radicals (.OH).  相似文献   
37.
A framework is presented showing the process of integrated resource planning in the electric power sector. This takes into account the traditional utility planning process, and shows how the use of advanced decision analysis tools would facilitate the integration of demand-side management (DSM) and environmental factors. The concept of influence diagram is introduced in the utility planning arena. Using the interdependent data analysis (IDA) technique, a way is shown to provide the probability estimates necessary for the influence diagram. The IDA technique allows the use of expert opinions and intuitive judgements to develop the necessary probability estimates. A sample case study is presented where the issue of environmental impact from stack emissions is incorporated. A base case coal option is compared against a gas turbine combined cycle (GTCC) alternative. Energy costs from these two options are compared by taking into account the capital, licensing, fuel, operation and maintenance, and emissions related costs.  相似文献   
38.
Toxic activity of leaf extracts of Polygonum hydropiper L. and Pogostemon parviflorus Benth. were tested in the laboratory against tea termite, Odontotermes assamensis Holm. Both the tested extracts caused mortality of the termite. The highest toxic activity (100%) was found in the 2.0% chloroform extracts of P. hydropiper. The chloroform extract of P. hydropiper was explored for possible mammalian toxicological effects. The LD50 was 758.58 mg/kg in male albino mice. Subcutaneous injection of sub-lethal dose of extract into male mice once a week for 6 weeks failed to express any significant influence on WBC, RBC count and blood cholesterol.  相似文献   
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40.
The aim of the study is to assess the agricultural drought risk condition in the context of global climate change in the western part of Bangladesh that covers about 45% area of the country for the period of 1960–2011. Drought Index (DI) and Drought Hazard Index (DHI) have been calculated by Markov Chain analysis and that of Drought Vulnerability Index (DVI) from socioeconomic and physical indicators. The DI values show that the northern part in general is more drought-prone, having less crops prospect, whereas the southern part is less drought-prone with high crop potentiality. The probability of extreme drought occurrence increases in recent decades in some parts as a result the drought events become more frequent in the areas. The DHI ranges from 15 to 32, and northern part suffers from more extreme drought hazards than that of southern part. DVI also indicates that northern part is exposed to high to very high drought vulnerability as higher percentage of illiterate people are involved in agricultural practices and high percentage of irrigation to cultivable land, but southern part exposed to moderate to low vulnerability because of low values of vulnerability indicators. Finally, agricultural drought exists at high risk condition in northern part and low in southern parts and 21.63, 26.54 and 29.68% of the area poses very high, high and moderate risk, respectively. So, immediate adaptation measures are needed keeping in mind climate features like rainfall and temperature variability, drought risk and risk ranking to make viable adaptation measures.  相似文献   
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