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51.
Air particulate samples collected during 1995–96 ata background site situated on the east coast of Thar Desert inRajsthan State of India were analysed for atmospheric dustloads (Suspended Particulate Matter) and elemental composition.The values of SPM ranged from 9 g M-3 to 97g M-3 with an average of 43 g M-3 except a fewepisodic values, which were 3 to 5 times higher than the averageduring summer months. The results for elemental composition ofthe particulate samples showed that the concentrations ofanthropogenic toxic trace elements viz. Br, Cr, Pb, Sb, Se and Znare lower by a factor of 2 to 10 as compared to urban areas. Thehigh enrichment factors for anthropogenic elements viz. Br, Pb,Sb and Zn show an input from coal/wood fuel burning andvehicular pollution at the sampling site. The depletion of Si inSPM samples shows long distance transport of dust to the samplingsite.  相似文献   
52.
Studies on marine sediments are extremely important since they act as ultimate sink of anthropogenic pollutants. The present study was conducted near Mumbai city of India to understand andassess the behaviour and fluxes of trace and toxic elements increek sediment. Seven sediment core samples were collected andanalysed for trace and toxic elements such as Fe, Cu, Pb, Zn, Rb and Sr in different sections of the core using EDXRF technique. The fluxes of the elements in each section of the core were calculated using the mass sedimentation rates derivedfrom 210Pb dating technique and the sediment density at each location. The estimated depositional fluxes of Fe, Rb and Sr in Zone-1 and Zone-3 are in the ranges of 0.4–0.5% cm-2yr-1; 4–6 g cm-2 yr-1 and 10–20 g cm-2 yr-1 respectively, where as they were about 3–4 times higher in zone-2 for the same elements. The depositionalfluxes of elements Cu (40–60 g cm-2 yr-1), Zn (35–43 g cm-2 yr-1) and Pb (6–12 g cm-2 yr-1) were also found to be higher in zone-2 compared tozone-1 and zone-3 which can be attributed to the release from thenewly developed chemical zone of Thane-Belapur industrial belt.  相似文献   
53.
Abstract: The International Union for Conservation of Nature (IUCN) Red List of Threatened Species was increasingly used during the 1980s to assess the conservation status of species for policy and planning purposes. This use stimulated the development of a new set of quantitative criteria for listing species in the categories of threat: critically endangered, endangered, and vulnerable. These criteria, which were intended to be applicable to all species except microorganisms, were part of a broader system for classifying threatened species and were fully implemented by IUCN in 2000. The system and the criteria have been widely used by conservation practitioners and scientists and now underpin one indicator being used to assess the Convention on Biological Diversity 2010 biodiversity target. We describe the process and the technical background to the IUCN Red List system. The criteria refer to fundamental biological processes underlying population decline and extinction. But given major differences between species, the threatening processes affecting them, and the paucity of knowledge relating to most species, the IUCN system had to be both broad and flexible to be applicable to the majority of described species. The system was designed to measure the symptoms of extinction risk, and uses 5 independent criteria relating to aspects of population loss and decline of range size. A species is assigned to a threat category if it meets the quantitative threshold for at least one criterion. The criteria and the accompanying rules and guidelines used by IUCN are intended to increase the consistency, transparency, and validity of its categorization system, but it necessitates some compromises that affect the applicability of the system and the species lists that result. In particular, choices were made over the assessment of uncertainty, poorly known species, depleted species, population decline, restricted ranges, and rarity; all of these affect the way red lists should be viewed and used. Processes related to priority setting and the development of national red lists need to take account of some assumptions in the formulation of the criteria.  相似文献   
54.

Climate change has become one of the most compelling fields of empirical research over the last couple of decades, partly due to its socio-economic impacts. Using a meta-analysis of 235 peer-reviewed articles published between January 2010 and July 2020, this paper appraises climate change adaptation (CCA) research in Nepal and draws lessons for future adaptation planning. The number of research is observed to have increased significantly in recent years (2015–2020) although there is no consistent pattern over the review period and at the thematic level. Findings submit that the agriculture and food security has the highest number of publications (37%) followed by gender equality and social inclusion (18%) and forest, biodiversity and watershed management (16%). There are no studies found in rural and urban settlement theme. Geographic distribution of CCA studies revealed that over 40% studies were carried out from central Nepal, while no study was conducted in ten districts of eastern and western Nepal. The study focus was also discrete, and the perception and attitude and impact assessment of climate change were common agendas; however, the drivers of change and options for adaptation were understudied. CCA with multipronged initiatives provide a broader understanding of dynamics and governance of climate change that not only affects rural livelihoods, but also influences regional and global environments and biodiversity.

  相似文献   
55.
This paper presents a comparative study of 222Rn emanation from the ore and backfill tailings in an underground uranium mine located at Jaduguda, India. The effects of surface area, porosity, 226Ra and moisture contents on 222Rn emanation rate were examined. The study revealed that the bulk porosity of backfill tailings is more than two orders of magnitude than that of the ore. The geometric mean radon emanation rates from the ore body and backfill tailings were found to be 10.01?×?10?3 and 1.03 Bq m?2 s?1, respectively. Significant positive linear correlations between 222Rn emanation rate and the 226Ra content of ore and tailings were observed. For normalised 226Ra content, the 222Rn emanation rate from tailings was found to be 283 times higher than the ore due to higher bulk porosity and surface area. The relative radon emanation from the tailings with moisture fraction of 0.14 was found to be 2.4 times higher than the oven-dried tailings. The study suggested that the mill tailings used as a backfill material significantly contributes to radon emanation as compared to the ore body itself and the 226Ra content and bulk porosity are the dominant factors for radon emanation into the mine atmosphere.  相似文献   
56.
In recent years, organizations are becoming environment conscious due to stringent laws, competitive advantages and increasing awareness of customers. They are integrating environmental practices into their operations to curb carbon emissions. Regulatory bodies are also imposing carbon policies to check emission. In this paper, we developed three models considering three carbon policies (I. carbon tax, II. strict cap and III. cap-and-trade) and have determined the optimal order quantity and number of shipments for a two-echelon supply chain. The objective is to minimize the total supply chain cost which comprises the ordering, setup, production, inventory holding and transportation costs. In Model I tax on carbon emissions has been included in the cost function; in Model II we have considered a strict carbon cap on the total carbon emission; and in Model III trading price of carbon is included in the cost function. A numerical study is given to illustrate the solution procedure. Further, sensitivity analyses are performed to examine the impact of the various parameters on the total cost and total emission.  相似文献   
57.
Deforestation in the biosphere reserves, which are key Protected Areas has negative impacts on biodiversity, climate, carbon fluxes and livelihoods. Comprehensive study of deforestation in biosphere reserves is required to assess the impact of the management effectiveness. This article assesses the changes in forest cover in various zones and protected areas of Nilgiri Biosphere Reserve, the first declared biosphere reserve in India which forms part of Western Ghats-a global biodiversity hotspot. In this study, we have mapped the forests from earliest available topographical maps and multi-temporal satellite data spanning from 1920’s to 2012 period. Mapping of spatial extent of forest cover, vegetation types and land cover was carried out using visual interpretation technique. A grid cell of 1 km?×?1 km was generated for time series change analysis to understand the patterns in spatial distribution of forest cover (1920–1973–1989–1999–2006–2012). The total forest area of biosphere reserve was found to be 5,806.5 km2 (93.8 % of total geographical area) in 1920. Overall loss of forest cover was estimated as 1,423.6 km2 (24.5 % of the total forest) with reference to 1920. Among the six Protected Areas, annual deforestation rate of >0.5 was found in Wayanad wildlife sanctuary during 1920–1973. The deforestation in Nilgiri Biosphere Reserve is mainly attributed to conversion of forests to plantations and agriculture along with submergence due to construction of dams during 1920 to 1989. Grid wise analysis indicates that 851 grids have undergone large-scale negative changes of >75 ha of forest loss during 1920–1973 while, only 15 grids have shown >75 ha loss during 1973–1989. Annual net rate of deforestation for the period of 1920 to 1973 was calculated as 0.5 followed by 0.1 for 1973 to 1989. Our analysis shows that there was large-scale deforestation before the declaration of area as biosphere reserve in 1986; however, the deforestation has drastically reduced after the declaration due to high degree of protection, thus indicating the secure future of reserve in the long term under the current forest management practices. The present work will stand as the most up-to-date assessment on the forest cover of the Nilgiri Biosphere Reserve with immediate applications in monitoring and management of forest biodiversity.  相似文献   
58.
Environmental Science and Pollution Research - Non-small cell lung cancer (NSCLC) is reported to have a high incidence rate and is one of the most prevalent types of cancer contributing towards 85%...  相似文献   
59.
Environmental Science and Pollution Research - Mutagens present in the environment manifest toxic effects and are considered as serious threat for human health and healthcare. Recent reports reveal...  相似文献   
60.
Environmental Science and Pollution Research - Coronavirus disease 2019 (COVID-19) is an infectious disease associated with the respiratory system caused by the SARS-CoV-2 virus. The aim of this...  相似文献   
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