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51.
The 1990s have seen a dramatic shift in capital flows into the developing world. Despite pledges made at the 1992 UNCED Conference in Rio de Janeiro, official development aid has declined in real terms. At the same time, private direct investment and lending to developing countries has risen from $44 billion at the beginning of this decade to $256 billion in 1997, supporting a record economic boom in the developing world. Developing countries have become significant sources of capital, as well as hosts to transnational corporations.
Cases illustrating the negative impacts of large investments under environmentally lax conditions are contrasted with the rise of environmental screening of funds by commercial entities, such as banks, insurance companies and investors. Although the new inflows of foreign capital may have brought the spread of Western consumerism, this new economic potential has also contributed cutting-edge environmental technologies, that may assist developing countries leapfrog over the most damaging phases of industrialization.
The article discusses the role of public lending agencies, international organizations and NGOs in setting the investment climate that determines the effects of foreign capital on the natural resources base, communities and the environment. Various mechanisms for defining environmental standards are discussed, and a more active role for governments and the United Nations is advocated.  相似文献   
52.
The author looks at economic and technical factors involved in the reuse of materials from demolition within the construction industry. Past experience in the use of such materials is reviewed and the results of a survey of the present usage of demolition materials in this country are presented. The prospects for increased utilisation are discussed in the light of the need to ensure the durability of building materials made from them.  相似文献   
53.
Ambient O3 concentrations in California's South Coast Air Basin (SoCAB) can be as much as 55% higher on weekends than on weekdays under comparable meteorological conditions. This is paradoxical because emissions of O3 precursors (hydrocarbons, CO, and nitrogen oxides [NOx]) are lower on weekends. Day-of-week emissions activity data were collected and analyzed to investigate the hypothesized causes of the "weekend O3 effect." Emission activity data were collected for various mobile, area, and point sources throughout the SoCAB, including on-road vehicles, lawn and garden equipment, barbecues, fireplaces, solvent use, and point sources with continuous emission monitoring data. The results of this study indicate significant differences between weekday and weekend emission activity patterns and emissions. Their combined effect results in a 12-18% decrease in reactive organic gases (ROGs) and a 35-41% decrease in NOx emissions on Saturdays and Sundays, respectively, relative to weekdays in summer 2000. These changes in emissions result in an increase of more than 30% in the ROG/NOx ratio on weekends compared with weekdays, which, along with lower NOx emissions, leads to increased O3 production on weekends.  相似文献   
54.
A methodology for rating the suitability of sites forthe location of industrial facilities is formulated and appliedto the case of a coal-fired power plant location. The methodologycomprises two major interlinked components: the environmentalplant location indexing component, which involves theidentification, scaling and weighting of environmentalsensitivity factors; and the impact analysis component, whichinvolves the superimposition of the pollution generation impactsof an industrial facility on spatially gridded zones of variousenvironmental sensitivities. For each rectangular areal unitdefined by a square grid, the Unit Pollution Potential Index isdetermined by the severity and distribution of key environmentalsensitivity factors and the coverage of superimposed pollutanteffects as determined by contaminant fate and transport models.For any alternative site of a planned facility, the summation ofthe unit indices over the area of influence of the facilityprovides the quantitative Pollution Index, which can be used as abasis for comparison of alternative sites for planned facilities.For this paper, this methodology is applied to the hypotheticalcase of the siting of a coal-fired power plant in thenortheastern region of the United States, in which threealternative sites are considered. The three sites: A, B and Cyielded indices of 47.83, 47.91 and 47.6, respectively, indicatingthat site C is the most suitable for siting the power plant.  相似文献   
55.
Forecast‐based drought early warning/early action has been hampered by both inadequate decision‐making frameworks and a lack of appropriate funding mechanisms. Rural communities in Nicaragua and Ethiopia that have participated in resilience‐building interventions of varying durations demonstrate the value of community‐based actions informed by early warning, forecasts and drought management advice, both before and during the agricultural season. While drought affected all crops negatively, participants were better able to mitigate impacts, were more organised in accessing relief and recovered more effectively. These results are consistent with other research on the cost/benefit of anticipatory actions, use of climate services and appropriate drought management advice. They also confirm the importance of embedding short‐term early action in long‐term resilience‐building. Despite this, formal systems, national and local, remain essentially unimplemented. Systems being developed at global level now need to be operationalised and translated into effective local drought management standard operating procedures for the most vulnerable.  相似文献   
56.
Proliferation of macroalgal mats is a frequent consequence of nutrient-driven eutrophication in shallow, photic coastal marine ecosystems. These macroalgae have the potential to significantly modify water quality, plankton productivity, nutrient cycling, and dissolved oxygen dynamics. We developed a model for Ulva lactuca and Gracilaria tikvahiae in Greenwich Bay, RI (USA), a shallow sub-estuary of Narragansett Bay, as part of a larger estuarine ecosystem model. The model predicts the biomass of both species in units of carbon, nitrogen, and phosphorus as a function of primary production, respiration, grazing, decay, and physical exchange, with particular attention to the effects of biomass layering on light attenuation and suppression of metabolic rates. The model successfully reproduced the magnitude and seasonal cycle of area-weighted and peak biomass in Greenwich Bay along with tissue C:N ratios, and highlighted the importance of grazing and inclusion of self-limitation primarily in the form of self-shading to overcome an order of magnitude difference in rates of production and respiration. Inclusion of luxury nutrient uptake demonstrated the importance of internal nutrient storage in fueling production when nutrients are limiting. Macroalgae were predicted to contribute a small fraction of total system primary production and their removal had little effect on predicted water quality. Despite a lack of data for calibration and a fair amount of sensitivity to individual parameter values, which highlights the need for further autecological studies to constrain formulations, the model successfully predicted macroalgal biomass dynamics and their role in ecosystem functioning. Our formulations should be exportable to other temperate systems where macroalgae occur in abundance.  相似文献   
57.
Prevention measures to reduce deaths and injuries due to domestic fires have included the provision of self-closing fire doors within dwellings. Such an approach however, is reliant on a behavioural response on behalf of the occupier(s). This research examined occupier behaviour in relation to self-closing fire doors. Forty semi-structured interviews were conducted with individuals inhabiting a new home. In all of the properties with self-closing fire doors, the occupants reported interfering with the self-closing mechanism of the doors. A quantitative survey was subsequently undertaken to obtain frequency data. In the majority of dwellings with fire doors occupiers reported propping these open in some way, or removing the self-closing mechanism from the door. The accounts suggest that, for fire doors to be an effective safety measure within dwellings, a greater emphasis needs to be placed on encouraging occupiers to adopt safe practices in relation to fire doors. Alternatively, other measures will need to be found to address the fire risk.  相似文献   
58.
The application of digital technology in conservation holds much potential for advancing the understanding of, and facilitating interaction with, the natural world. In other sectors, digital technology has long been used to engage communities and share information. Human development—which holds parallels with the nature conservation sector—has seen a proliferation of innovation in technological development. Throughout this Perspective, we consider what nature conservation can learn from the introduction of digital technology in human development. From this, we derive a charter to be used before and throughout project development, in order to help reduce replication and failure of digital innovation in nature conservation projects. We argue that the proposed charter will promote collaboration with the development of digital tools and ensure that nature conservation projects progress appropriately with the development of new digital technologies.  相似文献   
59.
Because the rise of cities in North America was much later than in many other parts of the world, their connections to the hinterland were influenced early in their development by railroads and steam-powered water transport. These fossil fuel-based links made it possible to widely separate the ??upstream?? autotrophic supporting systems from the heterotrophic cities. Here, we take a different look at the connection between a city (Providence, RI, USA) and its supporting natural systems by focusing on the export of industrial and metabolic wastes from the city to the ??downstream?? coastal ecosystem in Narragansett Bay. In this way, we can track the history of a city by examining the concentrations of nutrients, metals, and hydrocarbons in the water and sediments of the estuary. In the greater Providence metropolitan area at the head of Narragansett Bay, there was rapid population and industrial expansion during the 1800s without the proper infrastructure to deal with water supply for public safety and health. On the other hand, the absence of a public water supply kept industrial and metabolic wastes largely on land. However, from the fall of 1871, on with the construction of a public water supply and sewer system, human wastes began flowing into the estuary. By reconstructing the historical record of metals and other pollutants, we illustrate clear temporal and spatial gradients of urban impact on the bay. Unfortunately, while numerous studies during the 1970s and 1980s focused on documenting metal and hydrocarbon pollution in the bay, there has been little effort to quantify the impact of mitigation efforts that have greatly reduced the input of metals and hydrocarbons to the system. Nutrient reductions are more recent and ongoing.  相似文献   
60.
Whilst future air temperature thresholds have become the centrepiece of international climate negotiations, even the most ambitious target of 1.5 °C will result in significant sea-level rise and associated impacts on human populations globally. Of additional concern in Arctic regions is declining sea ice and warming permafrost which can increasingly expose coastal areas to erosion particularly through exposure to wave action due to storm activity. Regional variability over the past two decades provides insight into the coastal and human responses to anticipated future rates of sea-level rise under 1.5 °C scenarios. Exceeding 1.5 °C will generate sea-level rise scenarios beyond that currently experienced and substantially increase the proportion of the global population impacted. Despite these dire challenges, there has been limited analysis of how, where and why communities will relocate inland in response. Here, we present case studies of local responses to coastal erosion driven by sea-level rise and warming in remote indigenous communities of the Solomon Islands and Alaska, USA, respectively. In both the Solomon Islands and the USA, there is no national government agency that has the organisational and technical capacity and resources to facilitate a community-wide relocation. In the Solomon Islands, communities have been able to draw on flexible land tenure regimes to rapidly adapt to coastal erosion through relocations. These relocations have led to ad hoc fragmentation of communities into smaller hamlets. Government-supported relocation initiatives in both countries have been less successful in the short term due to limitations of land tenure, lacking relocation governance framework, financial support and complex planning processes. These experiences from the Solomon Islands and USA demonstrate the urgent need to create a relocation governance framework that protects people’s human rights.  相似文献   
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