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51.
Scientific evidence accumulating over the past decade documents that climate change impacts are already being experienced in the US Northeast. Policy-makers and resource managers must now prepare for the impacts from climate change and support implementing such plans on the ground. In this paper we argue that climate change challenges the region to maintain its economic viability, but also holds some opportunities that may enhance economic development, human well-being, and social justice. To face these challenges and seize these opportunities effectively we must better understand adaptation capacities, opportunities and constraints, the social processes of adaptation, approaches for engaging critical players and the broader public in informed debate, decision-making, and conscious interventions in the adaptation process. This paper offers a preliminary qualitative assessment, in which we emphasize the need for (1) assessing the feasibility and side effects of technological adaptation options, (2) increasing available resources and improving equitable access to them, (3) increasing institutional flexibility, fit, cooperation and decision-making authority, (4) using and enhancing human and social capital, (5) improving access to insurance and other risk-spreading mechanisms, and (6) linking scientific information more effectively to decision-makers while engaging the public. Throughout, we explore these issues through illustrative sectoral examples. We conclude with a number of principles that may guide the preparation of future adaptation plans for the Northeast.  相似文献   
52.
The papers in this Special Issue are the primary technical underpinnings for the Northeast Climate Impacts Assessment (NECIA), an integrated regional-scale assessment of projected climate change, impacts and options for mitigation and adaptation across the US Northeast. The consequences of future pathways of greenhouse gas emissions on projected climate and impacts across climate-sensitive sectors is assessed by using downscaled projections from three global climate models under both higher (Alfi) and lower (B1) emissions scenarios. The findings illustrate that near-term reductions in emissions can greatly reduce the extent and severity of regionally important impacts on natural and managed ecosystems and public health in the latter half of this century, and increase the feasibility that those impacts which are now unavoidable can be successfully managed through adaptation.  相似文献   
53.
In this investigation different bioassays were used to detect the physiological and genotoxic effects of water samples of mining lakes. Especially bioassays with higher plants were used like the duckweed bioassay with Lemna minor, the cress bioassay with Lepidium sativum, the Tradescantia‐micronucleus bioassay and the Arabidopsis bioassay. In addition the algae‐motility bioassay with Euglena gracilis were used. All these bioassays were found to be suitable to investigate mining lake samples of extreme acidic character. Four mining lakes (ML 107, ML 111, ML 117, ML F) were selected. They show equally low pH‐values, but differ in size, age, hydro‐chemical and biological state. The results demonstrated that it is possible to differentiate the mining lakes based on the results of bioassays. Samples of ML 107 and 111 showed significant physiological and genotoxic effects. Water samples of both lakes caused severe damages and decreased growth at the same dilution level in all plant bioassays. ML F causes different effects on bioassays. The highest negative effect was observed on root development of L. sativum. ML 117 did not show any effects on duckweed, algae, Tradescantia or Arabidopsis bioassays. There was only a slight effect on the root development in the cress bioassay.  相似文献   
54.
Acrylamide (AMD), a neurotoxin and suspected carcinogen, is present at concentrations of up to 0.05% in linear anionic polyacrylamide, which is under evaluation as a temporary sealant in unlined irrigation canal systems across the United States. We examined the microbially mediated degradation of AMD and diversity of AMD-degrading microbial physiotypes in the Rocky Ford Highline Canal, Colorado to better constrain the potential fate ofAMD in a canal environment. Microorganisms able to use AMD (500 mg L(-1)) as a sole nitrogen source were relatively abundant (2.3 x 10(3) to 9.4 x 10(3) cells mL(-1) in water and 4.2 x 10(3) to 2.3 x 10(5) cells g(-1) in sediment). Only sediment samples contained microorganisms able to use AMD as a sole carbon source. Acrylamide (up to 100 mg L(-1)) was efficiently removed from amended canal water and sediment slurries under aerobic conditions, but no AMD degradation was observed in abiotic controls. Anaerobic degradation of AMD by nitrate-, sulfate-, and iron-reducing microorganisms was also tested, with nitrate reducers affecting the highest amounts of AMD removal (70.3-85%) after 60 d. All representatives (n=15) from a collection of 256 AMD-degrading microbial isolates from Rocky Ford Highline Canal were closely related to well characterized environmental bacteria capable of facultative nitrate respiration. Our results demonstrate that natural microbial populations within this canal are capable of AMD degradation under aerobic and anaerobic conditions and that this degradation is performed by naturally abundant bacteria likely to be present in other freshwater irrigation canals or similar lotic habitats.  相似文献   
55.
In streams and creeks, the aquatic flora is exposed to fluctuating concentrations of herbicides during and following their application. Peak concentrations of herbicides, like the chloroacetanilide S-metolachlor, are usually detected following rain events. In this study, we assessed the effect of S-metolachlor pulse exposure on the algae Scenedesmus vacuolatus. We measured the time-dependency of effects during exposure on algae population and identified the algae development stage most sensitive to S-metolachlor. Furthermore, we assessed the time-to-recovery of the algae following exposure. A 6h pulse exposure at 598mugl(-1) was sufficient to inhibit cell reproduction by 50%. However, the exposure period had to coincide with the cell development stage specifically inhibited by S-metolachlor, which is the end of the cell growth phase. In algae populations composed of cells at all development stages, we initially observed an increase in the size of some algal cells, ultimately leading to an inhibition of the growth rate. In these experimental conditions, effects were observed after 18h of exposure and greatly increased with time. The recovery of algae following exposure to strongly inhibiting S-metolachlor concentrations was delayed and only occurred after 29h. These findings suggest that peak exposure to S-metolachlor may affect the growth of sensitive alga in surface waters, considering that the effects extend beyond the period of exposure.  相似文献   
56.
This study explores potential adaptation approaches in planning and management that the United States Forest Service might adopt to help achieve its goals and objectives in the face of climate change. Availability of information, vulnerability of ecological and socio-economic systems, and uncertainties associated with climate change, as well as the interacting non-climatic changes, influence selection of the adaptation approach. Resource assessments are opportunities to develop strategic information that could be used to identify and link adaptation strategies across planning levels. Within a National Forest, planning must incorporate the opportunity to identify vulnerabilities to climate change as well as incorporate approaches that allow management adjustments as the effects of climate change become apparent. The nature of environmental variability, the inevitability of novelty and surprise, and the range of management objectives and situations across the National Forest System implies that no single approach will fit all situations. A toolbox of management options would include practices focused on forestalling climate change effects by building resistance and resilience into current ecosystems, and on managing for change by enabling plants, animals, and ecosystems to adapt to climate change. Better and more widespread implementation of already known practices that reduce the impact of existing stressors represents an important “no regrets” strategy. These management opportunities will require agency consideration of its adaptive capacity, and ways to overcome potential barriers to these adaptation options.  相似文献   
57.
Adverse effects of agrochemicals on earthworms’ burrowing behaviour can have crucial impacts on the entire ecosystem. In the present study, we have therefore assessed short- and long-term effects on burrowing behaviour in the earthworm species Aporrectodea caliginosa and Lumbricus terrestris after exposure to a range of imidacloprid concentrations (0.2-4 mg kg−1 dry weight (DW)) for different exposure times (1, 7, 14 d). 2D-terraria were used for the examination of post-exposure short-term effects (24-96 h), while post-exposure long-term effects were assessed by means of X-ray burrow reconstruction in three dimensional soil cores (6 weeks). For the latter each core was incubated with two specimens of L. terrestris and four of A. calignosa. Short-term effects on the burrowing behaviour (2D) of A. caliginosa were already detected at the lowest test concentration (0.2 mg kg−1 DW), whereas such effects in L. terrestris were not observed until exposure to concentrations 10 times higher (2 mg kg−1 DW). For both species tested in the 2D-terraria, “total burrow length after 24 h” and “maximal burrow depth after 24 h” were the most sensitive endpoints. 3D reconstructions of the burrow systems made by both earthworm species in the repacked soil cores revealed a significant linear decrease in burrow volume with increasing imidacloprid concentration.Since many of the observed effects occurred at imidacloprid concentrations relevant to natural conditions and since reduced activities of earthworms in soils can have crucial impacts on the ecosystem level, our results are of environmental concern.  相似文献   
58.
The capacity of a concentrating solar thermal power (CSP) plant can be considered flexible and firm, just like that of a conventional steam cycle power station. Periods without sunshine can be bridged by thermal energy storage or fuel, enabling a CSP plant to deliver power on demand at any time. To this technical quality is added the economic quality of electricity costs that will be stable for a lifetime because they are mainly composed of capital costs, spare parts and personnel. CSP is competitive with power from fuel oil and moving to break even in costs with natural gas by around 2020 and steam coal by around 2025. Carbon dioxide emissions of 10–40 tons/GWh, land use of 250–550 m²/GWh and water consumption of 250 m³/GWh (using dry cooling) compare favorably with other energy sources. Environmental benefits, the technical imperative of firm and at the same time flexible power supply, and the economic targets of affordability and cost stability are the main reasons for a significant role for CSP in a sustainable future electricity mix. Two case studies show the different roles CSP can play north and south of the Mediterranean Sea, in one case importing CSP to Germany for flexible power and in the second case using CSP in Jordan to provide firm and at the same time renewable power capacity for the quickly growing electricity demand.  相似文献   
59.

The concluding document of the Rio conference in 1992, Agenda 21 for sustainable development, is implemented mainly at the local level in Germany. 'Sustainable development' is a model for the socially fair, economically competitive and ecologically viable development of the world. Local Agenda 21 (LA21) is a new municipal urban development process in which cities and their inhabitants orientate themselves to the model of sustainable development. Analysis of the LA21 process in Germany, and in particular that of the city of Osnabrück, shows deficits between the requirement of achieving sustainability and its practical realisation. Only a marginal development in the direction of sustainability has taken place. Concepts are lacking and the LA21 process is insufficiently integrated into conventional urban planning. Suggestions for the improvement of the LA21 process include the development of a concrete concept, together with the continuation of practical examples, the integration of four main areas (the environment, the social, the economy and the less developed world) and the strengthening of the popular themes in the LA21 process (such as climate protection and less developed countries' politics). El documento final de la conferencia de Rio en 1992 "La Agenda 21 para el desarrollo sostenible", es inplementado principalmente a nivel local en Alemania. "Desarrollo Sostenible" es una modelo para el desarrollo del mundo socialmente justo, ecónomicamente competitivo y ecológicamente viable. La "Agenda Local 21" es un nuevo proceso de desarrollo urbano municipal, en el cual las ciudades y sus habitantes se orientan hacia el modelo de desarrollo sostenible. El análisis del proceso de la Agenda Local 21 en Alemania y en particular el de la ciudad de Osnabrück muestra deficits entre el requerimiento de logro de sostenibilidad y su realización práctica. Solo un desarrollo marginal en la dirección de sostenibilidad ha sido llevado a cabo. Hay carencia de conceptos y el proceso de la Agenda Local 21 es insuficientemente integrado en la planeacio´n urbana convencional. Sugerencias para un mejoramiento del proceso de la AL 21 incluyen el desarrollo de un concepto concreto junto con la continuación de ejemplos practicos, integración de cuatro áreas principales (ambiental, social, económica, y el mundo menos desarrollado) y fortalecimiento de temas populares en el proceso de la AL 21 (tales como protección del clima y políticas de paises menos desarrollados).  相似文献   
60.
The authors introduce the concept of leader‐signaled knowledge hiding (LSKH) and conduct two studies observing what happens when leaders signal employees that knowledge hiding (KH) is practiced, tolerated, and expected. Social learning theory provides the basis for predicting that LSKH encourages subordinates to hide knowledge, even though they suffer from negative job attitudes in reaction. In Study 1, data measured at two time points (N = 1,162) shows that LSKH positively predicts KH among subordinates. The KH dimensions of evasive hiding and playing dumb (but not rationalized hiding) negatively relate to job satisfaction and positively affect turnover intentions. Study 2 (N = 1,169) replicates these results with cross‐sectional data. Moreover, Study 2 demonstrates that evasive hiding and playing dumb negatively affect empowerment, whereas rationalized hiding has a positive effect. Both studies reveal that subordinates will show less KH when they work under leaders who avoid LSKH and in turn have more job satisfaction, feel more empowered, and harbor fewer turnover intentions. The results in this study provide important practical implications for knowledge management activities.  相似文献   
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