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11.
A measuring campaign was conducted in the street canyon 'Runeberg street' in Helsinki in 1997. Hourly concentrations of carbon monoxide (CO), nitrogen oxides (NOX), nitrogen dioxide (NO2) and ozone (O3) were measured at the street and roof levels, and the relevant hourly meteorological parameters were measured at the roof level. The hourly street level measurements and on-site electronic traffic counts were conducted during the whole year 1997, and roof level measurements were conducted during approximately two months, from 3 March to 30 April in 1997. The Operational Street Pollution Model (OSPM) was used to calculate the street concentrations and the results were compared with the measurements. The overall agreement between measured and predicted concentrations was good for CO and NOx, but the model slightly overestimated the measured concentrations of NO2. The database, which contains all measured and predicted data, is available for a further testing of other street canyon dispersion models.  相似文献   
12.
Rats (Rattus norvegicus) were intraperitoneally injected with a 100 mg kg(-1) dosage of benzene, a toxic and carcinogenic agent widely used for industrial purposes. Changes in lactate dehydrogenase (LDH), alkaline phosphatase (ALP), alanine amino transferase (ALT), aspartate amino transferase (AST) activities in serum of rats were investigated at 2, 4, 8, 16, 32, and 64 h following injection. Serum physiological was administered to control group. Activities were measured using autoanalyzer. Benzene caused significant activations in LDH, ALP, and AST activities in the serum at some test hours (p < 0.05). When compared with the control groups, although an increase occurred in ALT activity, it was seem that this increase wasn't significant (p > 0.05).  相似文献   
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Journal of Material Cycles and Waste Management - This study aims to identify the amount of solid waste generation, composition, and characteristics of the Buleleng sub-district waste. The results...  相似文献   
15.
Controversy between alternative uses of forests in Finnish Upper Lapland has been going on for decades, and in recent years it has been escalated to a serious conflict. The core of the conflict is the adverse impacts of forestry on old forests which are important grazing areas for reindeer and which are regarded as intact nature and wilderness areas. This paper describes the experiences of applying multi-criteria decision analysis interview approach on this conflict. The approach provides tools for structuring the problem and preferences of the stakeholders as well as for analyzing the effects of different alternatives in a common framework. We focus on the practical experiences gained from the application of this approach in this context. Multi-criteria decision analysis was found to be a useful approach to evaluate the economic, ecological and cultural aspects of this intense conflict. The obtained experiences also support the view that the approach works best when tightly integrated into the planning process.  相似文献   
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The primary focus of many in-stream restoration projects is to enhance habitat diversity for salmonid fishes, yet the lack of properly designed monitoring studies, particularly ones with pre-restoration data, limits any attempts to assess whether restoration has succeeded in improving salmonid habitat. Even less is known about the impacts of fisheries-related restoration on other, non-target biota. We examined how restoration aiming at the enhancement of juvenile brown trout (Salmo trutta L.) affects benthic macroinvertebrates, using two separate data sets: (1) a before-after-control-impact (BACI) design with three years before and three after restoration in differently restored and control reaches of six streams; and (2) a space-time substitution design including channelized, restored, and near-natural streams with an almost 20-year perspective on the recovery of invertebrate communities. In the BACI design, total macroinvertebrate density differed significantly from before to after restoration. Following restoration, densities decreased in all treatments, but less so in the controls than in restored sections. Taxonomic richness also decreased from before to after restoration, but this happened similarly in all treatments. In the long-term comparative study, macroinvertebrate species richness showed no difference between the channel types. Community composition differed significantly between the restored and natural streams, but not between restored and channelized streams. Overall, the in-stream restoration measures used increased stream habitat diversity but did not enhance benthic biodiversity. While many macroinvertebrates may be dispersal limited, our study sites should not have been too distant to reach within almost two decades. A key explanation for the weak responses by macroinvertebrate communities may have been historical. When Fennoscandian streams were channelized for log floating, the loss of habitat heterogeneity was only partial. Therefore, habitat may not have been limiting the macroinvertebrate communities to begin with. Stream restoration to support trout fisheries has strong public acceptance in Finland and will likely continue to increase in the near future. Therefore, more effort should be placed on assessing restoration success from a biodiversity perspective using multiple organism groups in both stream and riparian ecosystems.  相似文献   
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We give reasons why demographic parameters such as survival and reproduction rates are often modelled well in stochastic population simulation using beta distributions. In practice, it is frequently expected that these parameters will be correlated, for example with survival rates for all age classes tending to be high or low in the same year. We therefore discuss a method for producing correlated beta random variables by transforming correlated normal random variables, and show how it can be applied in practice by means of a simple example. We also note how the same approach can be used to produce correlated uniform, triangular, and exponential random variables.  相似文献   
18.
This paper examines the relation between the results of epidemiologic studies of air pollution mortality and impact indicators that can be informative for environmental policy decisions. Using models that are simple and transparent, yet contain the essential features, it is shown that (1) number of deaths is not meaningful for air pollution, whereas loss of life expectancy (LLE) is an appropriate impact indicator; (2) the usual short-term (time series) studies yield a change in daily number of deaths attributable to acute effects of pollution, without any information on the associated LLE (although some information on this has recently become available by extending the observation window of time series); and (3) long-term studies yield a change in age-specific mortality, which makes it possible to calculate the total population averaged LLE (acute and chronic effects) but not the total number of premature deaths attributable to air pollution. The latter is unobservable because one cannot distinguish whether few individuals suffer a large or many suffer a small LLE. The paper calculates the LLE from exposure to PM10, as implied by the long-term mortality studies of adults and infants; population LLE for infants turns out to be an order of magnitude smaller than for adults. The LLE implied by short-term studies is a small fraction of the total loss implied by long-term studies, even if one assumes a very high loss per death. Applied to environmental policy, taking a permanent 50-70% reduction of PM10 as a reasonable goal, one finds a corresponding increase of average life expectancy in urban areas of the European Union (EU) and the United States of approximately four months.  相似文献   
19.
Forest and agroecosystem fire management in Ghana   总被引:1,自引:0,他引:1  
The threat of wildfires to the economic potential of forestry and agriculture is one of the persistent national and international concerns. Improving and applying indigenous wildfire management (IWM) approaches is seen as one of the main hopes for mitigating and adapting to this threat to rural forest communities. Identifying the contextual causes and adaptation measures practiced by local people is essential for planning an appropriate mechanism for IWM. Yet only limited studies are available on IWM practices and most of those studies were conducted outside of this study region. To fill this gap, this study examined the wildfire mitigation and adaptation methods of forest communities in Ghana using interviews with 266 farming households. Their perceptions of the causes, cost and risk factors were also examined. The result suggests that wildfires are annual events. More than half of the wildfires reported were caused by slash-and-burn land preparation, with hunting-related fires in second place. Forest households loose about 208 Ghana cedi (US$ 231 in 2006) in value due to damaged crops and tree seedlings annually (i.e. about 50% of annual income of a Ghanaian farmer). The respondents had the operational skill and coping abilities to deal with small-scale wildfires and were supported by well-established local arrangements, community rules and silvicutural techniques. In addition, they were well informed about the basic risk factors (e.g. fuel load, climate, and presence of ignition triggers) and how these can interact to cause devastating wildfire. Therefore it is critical that policies and institutions that promote IWM initiatives build on the strong underlying community knowledge and local networks to enhance their effectiveness.  相似文献   
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