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1.
The work presents the radioecological characterization of the new Brazilian uranium mining and milling site located in a semi-arid region of the country. The process characterization demonstrated that in heap leach plants most of the 226Ra remains in the leached ore. Despite the potential higher availability of radium isotopes in the soils of the studied region the lack of precipitation in that area reduces the leaching/mobilization of the radionuclides. High 226Ra and 228Ra concentrations were found in manioc while 210Pb was significant in pasture. It was suggested that a range from 10(-3) to 10(-1) may conveniently encompass most of the transfer factors (TF) values for soil/plant systems (i.e. involving different cultures, different soils and natural radionuclides). Impacts due to aerial transportation of aerosols and radon generated in the mining were proved to be minimal and restricted to an area not greater than 15 km2. Finally, uranium complexation by carbonates was shown to be the main mechanism responding for the elevated radionuclide concentration in groundwater. 相似文献
2.
Many international agreements, such as the 1992 UN Convention on Biological Diversity, posit that successful community-oriented (community-based) wildlife conservation depends on partnerships with stakeholders of different class, ethnicity, and gender. Gender is of particular interest because it often relates to environmental use, attitudes, and knowledge and operates across other key categories. This study uses fieldwork, interviews, and a survey of 52 project heads in India to address two research questions: (1) How are gender issues viewed by supervisors of community-based wildlife conservation projects, in relation to their work? (2) What types of resources would be most useful to project heads seeking to promote gender equity through their conservation work? The results suggest that while there is widespread support for integrating gender equity issues into community-oriented wildlife conservation, many believe that gender may be a potentially distracting and secondary issue. Several reasons for the variation in views were identified including the following: the dearth of relevant empirical research about gender issues in wildlife conservation; ambiguities about the concept of gender itself; and a lack of opportunities to critically discuss the role of gender equity issues for conservation. These factors may contribute to a disconnection between international rhetoric and on-the-ground practice as it relates to gender and community-oriented wildlife conservation. Increased opportunities for professional capacity building among project supervisors and staff members, coupled with increased collaboration between social and natural scientists, will be important for strengthening the links between international conservation policy and on-the-ground practice. 相似文献
3.
The Antarctic region is threatened by three major anthropogenic influences: climatic change brought about by increases in atmospheric carbon dioxide, the effects of persistent pollutants carried into the region via atmosphere and ocean, and the increase in Man's activities. Vulnerable ecosystems can be considered as those which are under direct pressure from Man's activities, whereas fragile ecosystems are the more likely to suffer irreversible change when perturbed, but are not necessarily threatened at present. Three of the main habitat types, terrestrial, inland waters, and islands, are likely to be fragile. However, all these can be conserved reasonably adequately with a system of protected and managed areas, so long as the area covered is adequate and representative. The fourth habitat type, the oceanic ecosystem, contains few fragile elements because it is dominated by the highly dynamic physical oceanic processes. Elements of the ecosystem are vulnerable to further exploitation, and although only the whales and some of the fish stocks can be regarded as fragile, there is considerable uncertainty as what synergistic effects exploitation of apparently key elements of the ecosystem, such as the krill, will have on other important components of the communities. The highly dynamic structure of oceanic environments renders the concept of conservation based on limited protected areas developed for terrestrial environments ineffective in the majority of marine environments. Instead the whole marine environment of the Antarctic region must be considered to be a single entity and managed as such. 相似文献
4.
Wetland ecosystems are of global significance having productive, regulatory and informative function. These wetlands are crucial
for the long-term protection of water sources, as well as the survival of its unique biodiversity. Most of the wetlands of
Turkey are now facing serious threat from the anthropogenic sources and now near to the verge of extinction. This study has
been carried out to monitor vegetation dynamics and ecological status of wetlands of Koyna basin at spatial and temporal scale.
This study has involved MODerate-resolution Imaging Spectroradiometer (MODIS) images of the year 2000, 2004 and 2008 on daily
basis with spatial resolution of 1 km. The MODIS 16 days composite NDVI time series products of 250-m spatial resolution from
year 2000 to 2008 has been utilized to monitor the ecological status of the wetlands. The European Nature Information System
habitat classification map, meteorological data (precipitation, temperature) coupled with field data has been utilized to
validate NDVI values of nine habitats in the wetlands. The time series analyses of NDVI data values have been correlated with
the groundwater level depth from 1996 to 2004. The overall analysis has shown a declining trend of NDVI over the year 2000
to 2008, indicated a degraded wetland condition in span of 9 years. 相似文献
6.
Alpha-autoradiographic and radiochemical studies of the distributions of transuranic nuclides in the tissues and organs of mussels collected from the vicinity of the British Nuclear Fuels plc reprocessing plant at Sellafield, Cumbria, England, appeared to require assessment also of baseline alpha-activities of natural 210 Po levels. Results for the latter were found to be in excess of the anthropogenic activities of Pu and Am isotopes. To ensure that the levels of 210 Po in Cumbrian mussels were not artificially enhanced by local discharges and in the absence of published data, mussels from remote British and French coastal sites were also analyzed. General similarities in 210Po concentrations (111 to 459 Bq kg −1 dry) found in mussels soft parts suggest that the 210Po levels in the Ravenglass mussels (279 Bq kg −1) are natural and largely unsupported by 210Pb; however these levels are as much as four times greater than the present day 239+240Pu concentrations in the same samples. As the transuranic nuclide content of Cumbrian mussels produces a major component of the local critical group radiation exposure from the Sellafield discharges, this finding places in some perspective the significance of the baseline natural radionuclide concentrations in generating total exposure of the public. More specifically, these findings severely limit the usefulness of alpha-autoradiographic studies for transuranic nuclides performed on such samples. Because of the recently lower concentrations of alpha-emitting transuranic nuclides (mainly 238Pu, 239+240Pu and 241Am) in the Ravenglass environment, natural 210Po is now a major contributor to alpha-track distributions in autoradiographic studies. 相似文献
7.
Despite the importance of neotropical cloud forests as providers of ecosystem services to society, they are one of the most threatened ecosystems in the world. We analysed the importance of three cloud forest reserves in central Colombia as providers of ecosystem services, as well as the social support to conservation actions in these ecosystems through willingness to pay (WTP) and willingness to give up time (WTT) estimates. Our results highlight the high commitment of all users of the cloud forest areas towards the conservation of the ecosystem services provided by these strategic ecosystems. We found that the most important perceived ecosystem services were water supply and habitat maintenance for species. Our findings also suggest that the respondents’ ecological knowledge (measured as the awareness of the ecosystem services supplied by cloud forests) was an important factor in determining both WTP and WTT for conserving cloud forests. Moreover, our results indicate that WTT should be a viable technique to explore individual preferences of different stakeholders towards conservation activities in cloud forests. Based on our results, we propose a conservation strategy of cloud forests that considers different users’ socio-economic and environmental characteristics, in which both experimental and experiential knowledge should be incorporated in order to promote collective action. 相似文献
8.
The purpose of this article is to analyze the challenges to, and opportunities for, increasing sustainable development (SD) co-benefits delivered by clean development mechanism (CDM) wind power projects in northeastern Brazil and the resulting implications for climate and energy policies. Five methodological phases were met: First, a documentary research was conducted in the main CDM database; second was a literature review, creating the analytical framework and a survey questionnaire needed to assess the SD co-benefits from the projects; third, documentary research was used to enable ex-ante analysis of the SD co-benefits proposed in the CDM Project Design Documents (PDDs); fourth, survey allowed for the analysis of SD co-benefits perceived by project entrepreneurs (ex-post analysis); and finally, a comparison between the ex-ante and ex-post analyses was completed. The results show the importance of carrying out SD co-benefit studies after the implementation of CDM projects in order to learn lessons for new mechanisms of climate governance. The lowest SD co-benefits were water management improvement in the project influence area, soil pollution prevention, health and safety improvements and technology transfer. The greatest opportunities for increasing SD co-benefits come from the environmental licensing process and the strengthening of Corporate Social Responsibility. The greatest challenges are new technology development, stakeholders’ engagement and SD co-benefit audits. We conclude that the improvement of multi-level climate and energy governance plays a key role in increasing SD co-benefits. 相似文献
10.
农村居民煤炭消费牵涉到农村居民生活方式与能源转型、北方供暖清洁化改革、大气污染治理等重大改革实践,如何准确理解和研判现有的农村居民煤炭消费现状,并进而识别出科学、有效的减煤措施,已成为改善农村居民能源结构、治理农村地区煤炭消费、改善北方地区大气质量的重要手段之一。然而,现有对农村居民煤炭消费的统计数据可能存在一定低估,基础性数据的匮乏与不足严重阻碍了科学研究和公共决策。为了准确了解我国农村居民煤炭消费的现状、特征与空间分布,本文采用第三次中国家庭能源消费调查数据对农村居民的煤炭消费进行了核算,并针对户均煤炭消费量和地区农村居民煤炭消费总量进行了比较,在此基础上还考察了气候差异、资源禀赋、收入水平等因素对农村居民煤炭需求的影响。研究结果表明,2014年中国农村居民生活用煤炭消费总量为6 585.7万tce,平均每户煤炭消费量为347.2 kgce,其中供暖用煤占比96.9%,烹饪用煤占比3.1%。各省的户均煤炭消费和煤炭消费总量呈现显著的空间差异,其中:东北、西部地区农村居民户均煤炭消费量显著高于其他地区,北京及周边的河北、山东、山西、内蒙、辽宁和天津7个省、市的农村居民共消费了全国55%的农村生活用煤,其中北京周边的河北、山东和山西三省农村居民消费了全国46.6%的农村煤炭消费。地区煤炭资源禀赋、农村居民住房面积与供暖用煤需求显著正相关,而冬季户外温度、居民收入水平同煤炭需求之间关系不显著。未来政府应通过改善农村居民民生需求、推动农村能源转型、提高农村能源统计水平等途径来有效治理农村散煤消费。 相似文献
11.
Groundwaters from the Sebkhet Essijoumi drainage basin, situated in northern Tunisia, West of the city of Tunis, were sampled and analyzed for uranium and radium isotopes. Low (234)U/(238)U activity ratios coupled with relatively high (228)Ra and (238)U concentrations were found in the Manouba plain phreatic aquifer, at the northern part of the basin, where remote sensing has indicated that this plain corresponds to the main humid zone of the area. Low (234)U/(238)U ratios probably reflected short residence time for waters in the Manouba plain, and high ratios longer residence time in the south, where water reaching the phreatic aquifer seems to have previously circulated in rocks constituting the southern hills. Assuming that, in the Manouba plain aquifer, the groundwater flows downstream from the Oued Lill pass area to the South-West of the Sebkha, the difference in the (228)Ra/(226)Ra activity ratio suggests that the residence time of water has been 2.8 years longer near the Sebkha than upstream. 相似文献
12.
Traditional research into sustainable design has typically focused on reducing the environmental impact of products during the manufacture and disposal stages of a products' lifecycle. The last decade, however, has seen an explosion of research into understanding and moderating user behaviour during the use phase of a products' lifecycle; often the most resource-intensive phase. One of the biggest factors that affects behaviour is a users cultural context; however, the effect of cultural context on design for sustainable behaviour has had little exploration in this relatively new research field. 相似文献
13.
The phosphate region located in the Northeast of Brazil covers an area of approximately 150 km long with an average width of 4 km, along the coast of the states of Pernambuco and Paraíba. The inhabitants of this area are exposed to natural radioactivity levels higher than the background values recorded in the literature, mainly due to the presence of uranium and its decay products in the phosphatic sediments. The main aim of this study was to determine the activity concentration of uranium and (226)Ra in foodstuffs cultivated in this area, where the phosphate mineral has been extracted. The activity concentrations found for uranium and (226)Ra in the foodstuffs analyzed varied from 13 to 186 mBq kg(-1) (wet weight), with a mean value of 46 mBq kg(-1) and from 43 to 2209 mBq kg(-1) (wet weight), with a mean value of 358 mBq kg(-1), respectively. The annual intake of these radionuclides, for rural residents, was 7.45 Bq for uranium and 69.3 Bq for (226)Ra. 相似文献
15.
我国现阶段65岁以上老年人享有较好的社会保障体系,具有一定的物质基础和精神需求,对出行旅游具有强烈的欲望.在我国人口老龄化趋势逐渐加重的驱使下,刺激老年人出行旅游能够极大的促进消费,带动内需增长.为了科学制定拉动老年人旅游的政策措施,本文从《中国统计年鉴》(2006-2013年)中选取65岁以上人口比、老年抚养比、城镇人口比重、城镇基本养老保险基金支出、文盲人口占15岁及以上人口、接受高等教育人数、以及地区最终消费支出作为主要的比较指标;从《中国旅游统计年鉴》(2006-2013年)中选取65岁以上旅游人数比与65岁以上人口旅游消费支出作为主要参考指标,分别对相关数据进行了灰色关联分析.分析结果显示,选取的比较指标与参考指标之间呈现了中等以上强度的关联性,关联度均在0.6以上,65岁以上人口、老年抚养比、城镇人口比重相对2个参考指标关联度最强,城镇人口数量与受教育情况业是影响65岁以上旅游人数的重要因素,分析结论可以作为国家和地方政府在制定养老产业相关政策时的重要参考.本研究的最后,提出了完善社会福利保障体系和旅游业法律法规,提高养老保险水平,保障老年人旅游市场安全及制定差异化价格战略等措施. 相似文献
16.
The study focuses on evaluating factors that farmers consider relevant in adopting cassava production in five semi-arid zone
of West African countries. The study is based on primary data randomly collected as part of collaborative study of cassava
in semiarid zones of Africa (COSCASSA) village level survey from five West African countries namely: Nigeria, Ghana, Chad,
Niger and Burkina Faso. This study models effects of farm, farmer and technology specific factors on the decision of semi
arid farmers to adopt cassava into their farming system. By way of threshold decision models—Probit and Logit models, the
estimation of each country and the pooled data adoption models reveal different adoption models for the countries considered.
For each country, different variables appeared as major adoption shifters. Comparatively, the adoption models for Nigeria
and whole region appear to have the highest significance variables, being seven in number. This is followed by Chad (6), Ghana
(4), and Burkina Faso and Niger with three each. For the variables considered, distance to nearby urban market appears a major
adoption shifter in all the country, except for Niger. This is closely followed by contact with extension, variety, pest/disease
resistance and livestock feeds, which appear significant in four of the countries. Membership of cooperative societies appears
as the least adoption predictor, which is only significant in Chad republic. The study therefore recognizes the importance
of varietial characteristics and farmers’ characteristics in acceptance of cassava as a major root tuber crop in the semi
arid region of West Africa.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
17.
Parabens are alkyl esters of p-hydroxybenzoic acid and are used as antimicrobial preservatives in a range of consumer products, including cosmetics, pharmaceuticals, and foodstuffs. Despite their widespread use, prior to this study, paraben concentrations in foodstuffs from China and human dietary exposure to these chemicals have been unknown. In this study, concentrations of six parabens were determined in 13 categories of food samples ( n = 282), including cereals and cereal products, meat, fish and seafood, eggs, dairy products, bean products, fruits, vegetables, cookies, beverages, cooking oils, condiments, and others, collected from nine cities in China. Almost all (detection rate: 99%) food samples contained at least one of the parabens analyzed, and the total concentrations (ΣParabens; sum of six parabens) ranged from below limit of quantification (LOQ) to 2530 ng/g fresh weight, with an overall mean value of 39.3 ng/g. Methyl paraben (MeP), ethyl paraben (EtP), and propyl paraben (PrP) were the major paraben analogs found in foodstuffs, and these compounds accounted for 59%, 24%, and 10%, respectively, of ΣParaben concentrations. Although the mean concentrations of ΣParabens varied among different categories of food items (from 0.839 ng/g in beverages to 100 ng/g in vegetables), the concentrations were not statistically significant among the 13 food categories, including canned foodstuffs. Estimated daily intake (EDI) of parabens was based on the measured concentrations in foods and the corresponding daily food ingestion rates. The mean and 95th percentile values for EDI were 1010 and 3040 ng/kg body weight (bw)/day for adult men and 1060 and 3170 ng/kg bw/day for adult women, respectively. 相似文献
18.
Fences are very common in rural areas, and represent important landscape elements in both tropical and temperate climate regions.
In spite of their marked presence and importance, fences have been little studied, principally in Brazil. The present study
examined the types of fences, the diversity of species used in their construction, as well as the diversity of their uses
in a rural community in the municipality of Caruaru, Pernambuco State, northeastern Brazil. Fifty meters of fence-line in
each of 50 rural properties in the community were examined, noting the diameter, height and identity of all vegetation elements
used in their composition. Semi-structured interviews were also held with their builders in order to obtain information concerning
fence uses. In the total of 2,500 linear meters of fence-line, 4,953 individual plant elements were identified, belonging
to 51 different species. A majority of the fence elements were non-living fence posts, although the number of living posts
was high. Of the total number of fence elements, 66.7% were native to the caatinga region. The large number of native species used as non-living fence posts indicates an intensive use of the caatinga vegetation and suggests the need to stimulate the use of living fence posts for conservation purposes. 相似文献
19.
Regional Environmental Change - The Middle East and North Africa (MENA) region emerges as one of the hot spots for worsening extreme heat, drought and aridity conditions under climate change. A... 相似文献
20.
Tourism is an activity of a person which includes traveling and staying in places that are outside of their location for business, vacation and other purpose. Large-scale tourism in developed and developing countries has positive and negative effects on the regional and national economies, local culture, physical infrastructure and environment. There are considerable gaps in research regarding tourism and livelihood in developing countries like Nepal. This research work aims at fulfilling such gap by assessing the impact of tourism on livelihood in Manaslu conservation area (MCA) of Nepal. We interviewed 76 household followed by three focus group discussions and five key informant interviews. The first-hand information collected at the site is complimented by socioeconomic and tourism-related secondary information. Socioeconomic variables such as marital status, size of household, education and landholding status had positive effect on tourism participation while livestock-holding status and occupation of the household had negative effect on tourism participation. Number of visitors is increasing in MCA in recent years, and tourism participation is helping local people to earn more money and improve their living standard. So, awareness and education related to tourism, gender empowerment of women, advertisement and publicity on tourism promotion, adequate subsidy and training on ecotourism and skill development trainings on handicraft are recommended. 相似文献
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