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111.

Background

Globally, every year several hundred million tons of problematic, e.g. chemical, wastes are generated stemming to more than 90% from the 25 OECD countries. Due to their partly considerable toxicity special and often expensive measures are required for their disposal. According to the Secretary of the ‘Basel Convention on the Control of Transboundary Movements of Hazardous Waste and Their Disposal’ annually at least 8.5 million tons of wastes are transboundarily traded. Although the ‘Basel Convention’ has set up rules how to handle international waste streams, certain waste amounts are illegally transported from the OECD countries to developing countries — basically for reasons of expenses. Often an environmental safe treatment of toxic waste is not ensured or even not possible in the receiving countries. As set forth in a report of the European Network for the Implementation and Enforcement of Environmental Law (IMPEL) published in 2006, the illegal trade with toxic waste has steadily increased. 3000 shipping documents of 17 European seaports were examined and 258 cargo holds were inspected showing that 68 of 140 waste shippings were illegal. Preventing illegal transports of waste meets with various obstacles. Controlling measures require considerable personal, technical, and logistic resources that are not sufficiently available in each country concerned. Missing or ineffective administrative structures hamper fast actions to stop illegal waste disposal. Partly, the political will to take the necessary steps is lacking. An additional problem is the fact that waste that is obtained from the regular shipping business is not subject to the Basel Convention but to the ‘International Convention for the Prevention of Pollution from Ships’. The implementing statures are summarized in the document MARPOL 73/78; the International Maritime Organization (IMO) is responsible. Identifying the origin of waste and thus defining the responsibility occasionally raises difficulties. This background provides a basis to try to reconstruct the course of events concerning the disposal of chemical waste in Abidjan.

Methods

Several information sources were utilized to reconstruct the course of events at Abidjan in August 2006; e.g. public press, declarations of international governmental organizations, especially of the UN and of its subsidiary organizations, communiqués of the Secretary of the Basel Convention, and statements of several NGOs. Nevertheless a complete reconstruction of the incident is impossible, since a detailed and reliable historical report is not available. Furthermore the responsible politicians have not undertaken significant efforts to shed light upon the incident. Additionally relevant documents of the participating companies are not available to the public.

Conclusions

The analyzed incident makes obvious that the control mechanisms of the Basel Convention can be circumvented. It remains unclear who has to take the political responsibility for the death of 10 people and for the health defects of thousands of humans. Possible civil and criminal consequences are not foreseeable for the actors and company owners involved in the illegal waste dumping. The people of Abidijan are confronted with unresolved questions regarding the occurrence of chronic diseases and possible long-term effects of remaining waste portions.

Recommendations and Perspectives

The incident demonstrates that the control of the transboundary transport and disposal of hazardous waste needs to be enforced and legal grey areas should be eliminated. It should be a task of the OECD countries and of all other economically and technically developed countries and organizations to support the developing countries’ efforts to build up the personal, technical, and infrastructural capacities for an efficient control of waste imports.  相似文献   
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113.
The yearly influx of Sargassum onto the beaches of northwest Florida is considered a nuisance to some and a necessity to others. In Pensacola Beach, the Santa Rosa Island Authority rakes the wrack with mechanical beach cleaners to improve the aesthetic quality for beachgoers. The purpose of this study was three-fold: to evaluate the local faunal use of Sargassum wrack, to gauge public perception of Sargassum on the beach, and to test whether public perception of the beauty of the beach, the necessity of raking, and the likelihood of visiting could be influenced by a simple educational sign. A two-part methodology consisted of 1) systematic observation of faunal use, and 2) interviews of 200 beachgoers via a detailed pre-post/post only public use survey. Results showed that 11 of the 22 species of shorebirds documented, including two uncommon migrants, were observed using Sargassum wrack to forage, rest, and hide. Public survey results demonstrated that although beachgoers generally considered themselves to be “ecofriendly”, their perceptions of Sargassum wrack can be positively influenced through environmental education such as informative signage on the beach. In conclusion, Sargassum wrack provides valuable additional habitat to shorebirds and other critters, and that leaving the beach wrack to naturally become part of the ecosystem would not deter most beachgoers (70%) from visiting Pensacola Beach. This research contributes valuable information to coastal managers and other stakeholders for improved ecosystem protection and management.  相似文献   
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115.
Climate change is a fundamental aspect of the Anthropocene. Climate assessments are frequently undertaken to evaluate climate change impacts, vulnerability, and adaptive capacity. Assessments are complex endeavors with numerous challenges. Five aspects of a climate assessment that can be particularly challenging are highlighted: choice of assessment strategy, incorporation of spatial linkages and interactions, the constraints of climate observations, interpretation of a climate projection ensemble, uncertainty associated with weather/climate dependency models, and consideration of landscape–climate influences. In addition, a climate assessment strategy that incorporates both traditional “top-down” and “bottom-up” methods is proposed for assessments of adaptation options at the local/regional scale. Uncertainties associated with climate observations and projections and with weather/climate dependency (i.e., response) models are incorporated into the assessment through the “top-down” component, and stakeholder knowledge and experience are included through the “bottom-up” component. Considerable further research is required to improve assessment strategies and the usefulness and usability of assessment findings. In particular, new methods are needed which better incorporate spatial linkages and interactions, yet maintain the fine grain detail needed for decision making at the local and regional scales. Also, new methods are needed which go beyond sensitivity analyses of the relative contribution of land use and land cover changes on local/regional climate to more explicitly consider landscape–climate interactions in the context of uncertain future climates. Assessment teams must clearly communicate the choices made when designing an assessment and recognize the implications of these choices on the interpretation and application of the assessment findings.  相似文献   
116.
Rats are major reservoirs of leptospirosis and considered as a main threat to biodiversity. A recent introduction of Rattus rattus to the island of Futuna (Western Polynesia) provided the opportunity to test if a possible change in species composition of rat populations would increase the risk of leptospirosis to humans. We trapped rodents on Wallis and Futuna and assessed Leptospira carriage in 357 rodents (Rattus norvegicus, R. rattus, Rattus exulans, and Mus domesticus) from 2008 to 2012. While Leptospira prevalence in rodents and the composition of rat populations on Futuna fluctuated with rainfall, the biomass of Leptospira-carrying rodents has been continuously rising from 2008 to 2012. Our results suggest that the introduction of R. rattus increases the risk to humans being infected with leptospirosis by rats.  相似文献   
117.
Marine protected areas (MPAs) provide an important tool for conservation of marine ecosystems. To be most effective, these areas should be strategically located in a manner that supports ecosystem function. To inform marine spatial planning and support strategic establishment of MPAs within the California Current System, we identified areas predicted to support multispecies aggregations of seabirds ("hotspots"). We developed habitat-association models for 16 species using information from at-sea observations collected over an 11-year period (1997-2008), bathymetric data, and remotely sensed oceanographic data for an area from north of Vancouver Island, Canada, to the USA/Mexico border and seaward 600 km from the coast. This approach enabled us to predict distribution and abundance of seabirds even in areas of few or no surveys. We developed single-species predictive models using a machine-learning algorithm: bagged decision trees. Single-species predictions were then combined to identify potential hotspots of seabird aggregation, using three criteria: (1) overall abundance among species, (2) importance of specific areas ("core areas") to individual species, and (3) predicted persistence of hotspots across years. Model predictions were applied to the entire California Current for four seasons (represented by February, May, July, and October) in each of 11 years. Overall, bathymetric variables were often important predictive variables, whereas oceanographic variables derived from remotely sensed data were generally less important. Predicted hotspots often aligned with currently protected areas (e.g., National Marine Sanctuaries), but we also identified potential hotspots in Northern California/Southern Oregon (from Cape Mendocino to Heceta Bank), Southern California (adjacent to the Channel Islands), and adjacent to Vancouver Island, British Columbia, that are not currently included in protected areas. Prioritization and identification of multispecies hotspots will depend on which group of species is of highest management priority. Modeling hotspots at a broad spatial scale can contribute to MPA site selection, particularly if complemented by fine-scale information for focal areas.  相似文献   
118.
Mandatory or voluntary reductions in ship speed are a common management strategy for reducing deleterious encounters between large ships and large whales. This has produced strong resistance from shipping and marine transportation entities, in part because very few studies have empirically demonstrated whether or to what degree ship speed influences ship-whale encounters. Here we present the results of four years of humpback whale sightings made by observers aboard cruise ships in Alaska, representing 380 cruises and 891 ship-whale encounters. Encounters occurred at distances from 21 m to 1000 m (x = 567 m) with 61 encounters (7%) occurring between 200 m and 100 m, and 19 encounters (2%) within 100 m. Encounters were spatially aggregated and highly variable across all ship speeds. Nevertheless a Bayesian change-point model found that the relationship between whale distance and ship speed changed at 11.8 knots (6.1 m/s) with whales encountering ships, on average, 114 m closer when ship speeds were above 11.8 knots. Binning encounter distances by 1-knot speed increments revealed a clear decrease in encounter distance with increasing ship speed over the range of 7-17 knots (3.6-8.7 m/s). Our results are the first to demonstrate that speed influences the encounter distance between large ships and large whales. Assuming that the closer ships come to whales the more likely they are to be struck, our results suggest that reduced ship speed may be an effective management action in reducing the probability of a collision.  相似文献   
119.
Same-sex sexual behaviors are well documented in both captive and wild animals. In monogamous species, these behaviors are often exclusive, each individual having only one same-sex partner. A bias in sex ratio has been proposed as a social context yielding same-sex pair-bonding, but this hypothesis has rarely been tested. Focusing on a life-long pair-bonding songbird, the zebra finch Taeniopygia guttata, we tested whether same-sex pairing results from a shortage of individuals of the opposite sex. By experimentally skewing the sex ratio towards members of one sex, we observed a greater proportion of same-sex pair-bonds of that sex. Moreover, we assessed whether the quality and stability of social interactions were equivalent in same-sex and male–female pairs. Male–male and female–female same-sex bonds display the same behavioral characteristics as male–female ones: they are intense, highly selective, and stable affinitive relationships involving the same behavioral displays already described in wild birds. Moreover, same-sex male bonds were sufficiently strong not to split up when individuals were given the opportunity to reproduce with females. Because the pair-bond in socially monogamous species represents a partnership that may give advantages for survival (e.g., resources defense, fighting against predators, etc.), we propose that same-sex pairing in the zebra finch may result from the pressure to find a social partner.  相似文献   
120.
Many annual cropping lands are being converted to perennial pasture in humid and subhumid areas of the USA as the economic, social, and environmental benefits of managed grazing become evident. Recent evidence about the positive effects of plant diversity on productivity is driving farmers towards management for more complex species mixes than were promoted historically for grazed pastures, but this emphasis has highlighted a lack of understanding about plant community management in pastures. To better understand this system we examined sources of variability in the plant community of a subhumid grassland that was subjected to combinations of disturbance (graze or burn), and amendment (nitrogen, carbon, or ambient), and native grass seeding treatments over 3 years (2004 to 2006). We estimated species cover five times during the study period and ordinated these data with nonmetric multidimensional scaling (NMS). The ordination explained 80% of the variation in the plant community data set. Variance in ordination site scores was ascribed to management (disturbance, soil amendment, and native grass seeding time), the environment (year, season within year, and block), or unexplained (residual) realms with a linear mixed-effects model. The overwhelming source of variability in the plant community (62–99%) was attributed to management. Ordination results illustrated that plant groups sorted out along management gradients: burned plots were shifted towards grasses while forbs and clovers were associated with grazed plots. We demonstrate how a community-level approach can be used to evaluate management regimes in agroecosystems. Our results indicate that disturbance and soil amendments can be used to shape plant communities in subhumid grasslands for specific agronomic and conservation goals.  相似文献   
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