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211.
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the global environment and are subsequently transported into aquatic sediments. As PAHs are formed by various processes, source identification using diagnostic ratios can provide insight to PAH emission sources to distinguish between pyrogenic and petrogenic PAH sources. PAH diagnostic ratios were applied as a forensic source apportionment technique to assess aggregate historical sediment data from 31 small craft harbors (SCHs) across Nova Scotia, Canada. Multiple diagnostic ratios suggest that PAHs present in Nova Scotia SCH sediments are pyrogenic (combustion) in origin, while consistently suggesting that coal‐related PAH sources are potential dominant specific sources. National Institute of Standards and Technology Standard Reference Materials (SRMs) were used as reference for coal tar, urban dust, and diesel exhaust particulates in ratio applications. The SRM for coal tar was most similar to Nova Scotia SCH sediments in multiple ratio applications. Diagnostic ratio results were corroborated by comparing the PAH profile of sediments to source profiles from the literature. Results indicate that Nova Scotia SCH sediments follow global trends by exhibiting a dominant pyrogenic PAH signature, and the specific coal‐related PAH signature of Nova Scotia SCH sediments may be influenced by contamination inputs related to historical industrial coal mining and combustion activities in the province.  相似文献   
212.
The good governance of institutions and regimes requires accountability suited to the particular context of each institution and regime. The paper examines the nature of accountability in climate change governance using the Caribbean region as a case study. In doing so, the paper makes two original contributions. First, using insights from the environmental governance literature, it presents a conceptual framework that categorises the types (levels, relationships and mechanisms) of accountability in governance that can be used to test accountability. The accountability framework comprises two levels (internal/external accountability); four relationships (normative, relational, decision and behavioural); and four mechanisms or processes through which accountability can be exercised (certification, monitoring, participation by stakeholders in the overseeing of projects and self-reporting). Second, through an analysis of survey and interview responses from Caribbean climate change experts, it reports on the nature of accountability in climate change governance in the context of Caribbean Small Island Developing States. To do this, first it identifies the actors involved in Caribbean climate governance at the regional and national scales. Then, using the framework, it examines which levels, relationships and processes exist within and between climate governance regional institutions, international partners, government agencies, non-governmental organisations and the private sector for climate change adaptation and mitigation efforts. The paper draws two main conclusions: first, generally actors valued accountability as a good governance norm. Secondly, limited resources and the perception that using the accountability mechanisms will retard policy implementation led to low levels of accountability in practice. Finally, the study examined how accountability can be enhanced in the climate change sector by ensuring that each of the elements of the framework is operationalised for both state and non-state climate change projects.  相似文献   
213.
Climate change and accelerating socioeconomic developments increasingly challenge flood-risk management in the Vietnamese Mekong River Delta—a typical large, economically dynamic and highly vulnerable delta. This study identifies and addresses the emerging challenges for flood-risk management. Furthermore, we identify and analyse response solutions, focusing on meaningful configurations of the individual solutions and how they can be tailored to specific challenges using expert surveys, content analysis techniques and statistical inferences. Our findings show that the challenges for flood-risk management are diverse, but critical challenges predominantly arise from the current governance and institutional settings. The top-three challenges include weak collaboration, conflicting management objectives and low responsiveness to new issues. We identified 114 reported solutions and developed six flood management strategies that are tailored to specific challenges. We conclude that the current technology-centric flood management approach is insufficient given the rapid socioecological changes. This approach therefore should be adapted towards a more balanced management configuration where technical and infrastructural measures are combined with institutional and governance resolutions. Insights from this study contribute to the emerging repertoire of contemporary flood management solutions, especially through their configurations and tailoring to specific challenges.  相似文献   
214.
Environmental justice addresses inequitable distributions of health risks from exposure to pollution and other hazards. Appalachian residents of southeastern Ohio who live along the Ohio River are disproportionately subject to industrial pollution. Of particular concern is the DuPont Washington Works plant where perfluorooctanoic acid, or C8, was used to make consumer products. Although company officials became aware in 1984 that the water supply of Little Hocking, Ohio, was tainted with C8 coming from its plant, residents were not notified until 2002. Subsequent studies determined a number of health problems, including cancer, are linked to residents’ exposure. This qualitative study asked Little Hocking residents and environmental regulators if they consider C8 contamination in Little Hocking an injustice. Results indicate a lack of consensus – even among affected residents – concerning DuPont's® actions as constituting an injustice. This finding, among others, is used to argue that many residents in Little Hocking, through their association with DuPont®, benefit from class-based forms of privilege and seek to maintain them in the context of immobility and economic uncertainty. This explains why some communities may be considered an environmental justice community from an academic standpoint, but not self-identify as such. However, maintaining privilege at the local scale in the context of weak regulation enhances exploitation in Little Hocking while contributing to power at extra-local scales. Thus, environmental justice activists in white, working-class communities must overcome the challenge posed by privilege that defends the contaminated status quo.  相似文献   
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216.
Portman ME  Nathan D  Levin N 《Ambio》2012,41(7):670-681
Marine protected areas (MPAs) are critical to the well-being of threatened ecosystems and thus can be highly beneficial to humans, especially to those residing nearby. We explore the qualities of 117 MPAs in the Mediterranean basin and develop a taxonomy of their characteristics. We relate the spatial distribution of the MPAs to the various characteristics of the taxonomy (size, distance from shore, protection levels, management regimes, etc.) and to areas of high human impact and influence levels. To do this we use information on biogeographic regions and information from two different human influence models; one model developed for the marine environment and one covering the littoral terrestrial environment. Our analysis provides insights to planners and managers working in a regional capacity and trying to build MPA networks. Generally, current MPAs have not been established in high impact areas despite their being close to shores containing intense human activity. Decision-makers wishing to design and establish new MPAs may seek out areas of high cumulative human impacts (near the marine-terrestrial interface) or avoid them depending on marine conservation objectives, including the desire to vary types of MPAs within a network. Limitations of our analysis and methodology indicate areas for further research.  相似文献   
217.
ABSTRACT: Shallow ground water in areas of increasing urban development within the Upper Colorado River Basin was sampled for inorganic and organic constituents to characterize water‐quality conditions and to identify potential anthropogenic effects resulting from development. In 1997, 25 shallow monitoring wells were installed and sampled in five areas of urban development in Eagle, Grand, Gunnison, and Summit Counties, Colorado. The results of this study indicate that the shallow ground water in the study area is suitable for most uses. Nonparametric statistical methods showed that constituents and parameters measured in the shallow wells were often significantly different between the five developing urban areas. Radon concentrations exceeded the proposed USEPA maximum contaminant level at all sites. The presence of nutrients, pesticides, and volatile organic compounds indicate anthropogenic activities are affecting the shallow ground‐water quality in the study area. Nitrate as N concentrations greater than 2.0 mg/L were observed in ground water recharged between the 1980s and 1990s. Low concentrations of methylene blue active substances were detected at a few sites. Total coliform bacteria were detected at ten sites; however, E. coli was not detected. Continued monitoring is needed to assess the effects of increasing urban development on the shallow ground‐water quality in the study area.  相似文献   
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219.
High selenium (Se) concentrations have been found in surface waters in the Kendrick Reclamation Project, Wyoming. Precipitation and irrigation water moving over seleniferous soils are contributing causes, and drought may exacerbate this. This study surveyed Se concentrations and discharges in local surface streams, irrigation drains, and the delivery canal. Sites were sampled monthly and analyzed for Se and total suspended solids (TSS). A completely randomized design with two factors (soil parent material and location, inside or outside irrigation district) was used. Mean Se concentrations were 64 μg L???1 inside the irrigation district on shale soils, 17 μg L???1 inside the district off shale soils, 5 μg L???1 outside the district on shale soils, and 3 μg L???1 outside the district off shale soils. Correlations between discharge and Se concentrations were generally negative, while correlations between discharge and Se load were generally positive. There was little correlation between load and concentration, and little correlation between TSS and Se. A comparison of Se concentrations in streams and drains showed Se concentrations were significantly higher (p?<?0.001) in streams during the irrigation season, but not in the off-season (p?=?0.515). We conclude that higher discharges decrease Se concentration, but increase load. Conversion from flood to sprinkle irrigation may increase Se concentrations by reducing discharge, but decrease Se loads going into the N. Platte River, and will likely alter the timing and magnitude of flows. Both load and concentration should be considered when implementing Se regulations and standards.  相似文献   
220.
The quality of the water in a uranium-ore-mining area located in Caldas (Minas Gerais State, Brazil) and in a reservoir (Antas reservoir) that receives the neutralized acid solution leaching from the waste heaps generated by uranium mining was investigated. The samples were collected during four periods (October 2008, January, April and July 2009) from six sampling stations. Physical and chemical analyses were performed on the water samples, and the data obtained were compared with those of the Brazilian Environmental Standards and WHO standard. The water samples obtained from waste rock piles showed high uranium concentrations (5.62 mg L?1), high manganese values (75 mg L?1) and low average pH values (3.4). The evaluation of the water quality at the point considered the limit between the Ore Treatment Unit of the Brazilian Nuclear Industries and the environment (Consulta Creek) indicated contamination by fluoride, manganese, uranium and zinc. The Antas reservoir showed seasonal variations in water quality, with mean concentrations for fluoride (0.50 mg L?1), sulfate (16 mg L?1) and hardness (20 mg L?1) which were low in January, evidencing the effect of rainwater flowing into the system. The concentrations for fluoride, sulfate and manganese were close or above to the limits established by current legislation at the point where the treated mining effluent was discharged and downstream from this point. This study demonstrated that the effluent discharged by the UTM affected the quality of the water in the Antas reservoir, and thus the treatments currently used for effluent need to be reviewed.  相似文献   
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