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41.
Citizen science has been gaining momentum in the United States and Europe, where citizens are literate and often interested in science. However, in developing countries, which have a dire need for environmental data, such programs are slow to emerge, despite the large and untapped human resources in close proximity to areas of high biodiversity and poorly known floras and faunas. Thus, we propose that the parataxonomist and paraecologist approach, which originates from citizen‐based science, is well suited to rural areas in developing countries. Being a paraecologist or a parataxonomist is a vocation and entails full‐time employment underpinned by extensive training, whereas citizen science involves the temporary engagement of volunteers. Both approaches have their merits depending on the context and objectives of the research. We examined 4 ongoing paraecologist or parataxonomist programs in Costa Rica, India, Papua New Guinea, and southern Africa and compared their origins, long‐term objectives, implementation strategies, activities, key challenges, achievements, and implications for resident communities. The programs supported ongoing research on biodiversity assessment, monitoring, and management, and participants engaged in non‐academic capacity development in these fields. The programs in Southern Africa related to specific projects, whereas the programs in Costa Rica, India, and Papua New Guinea were designed for the long term, provided sufficient funding was available. The main focus of the paraecologists’ and parataxonomists’ activities ranged from collection and processing of specimens (Costa Rica and Papua New Guinea) or of socioeconomic and natural science data (India and Southern Africa) to communication between scientists and residents (India and Southern Africa). As members of both the local land user and research communities, paraecologists and parataxonomists can greatly improve the flow of biodiversity information to all users, from local stakeholders to international academia.  相似文献   
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Environmental Chemistry Letters - Activated carbon is a material for many adsorption applications, combining low-cost and high-quality properties. Many sources of activated carbon have...  相似文献   
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The Natura 2000 network was established across the European Union’s (EU) Member States with the aim to conserve biodiversity, while ensuring the sustainability of human activities. However, to what kind and to what extent Natura 2000 sites are subject to human activities and how this varies across Member States remains unspecified. Here, we analyzed 111,269 human activity records from 14,727 protected sites in 20 Member States. The frequency of occurrence of activities differs among countries, with more than 86 % of all sites being subjected to agriculture or forestry. Activities like hunting, fishing, urbanization, transportation, and tourism are more frequently recorded in south European sites than in northern or eastern ones. The observed variations indicate that Natura 2000 networks are highly heterogeneous among EU Member States. Our analysis highlights the importance of agriculture in European landscapes and indicates possible targets for policy interventions at national, European, or “sub-European” level. The strong human presence in the Natura 2000 network throughout Member States, shows that conservation initiatives could succeed only by combining social and ecological sustainability and by ensuring the integration of policies affecting biodiversity.  相似文献   
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This study proposes the valuation of wetland functions as an alternative to the conventional approach to wetland valuation, in order to derive indicators for decision-making in wetland management. It is illustrated that these functions can be valuated in terms of the goods and services they provide to society. Using a functional approach, the functions are identified and the goods and services they provide are explicitly allocated among them; then, the latter are valuated with the Contingent Valuation method. Statistical analysis of the data provides welfare measures that reflect the value of these functions. It is argued that the values of separate functions are more useful in policy-making than their aggregated value.
Athanasios RagkosEmail: Phone: +30-2310-998826Fax: +30-2310-998828
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Seventeen polycyclic aromatic hydrocarbons (PAHs) were studied in surface waters (including particulate phase) from the Chenab River, Pakistan and ranged from 289-994 and 437-1290 ng l(-1) in summer and winter (2007-09), respectively. Concentrations for different ring-number PAHs followed the trend: 3-rings > 2-rings > 4-rings > 5-rings > 6-rings. The possible sources of PAHs are identified by calculating the indicative ratios; appropriating petrogenic sources of PAHs in urban and sub-urban regions with pyrogenic sources in agricultural region. Factor analysis based on principal component analysis identified the origins of PAHs from industrial activities, coal and trash burning in agricultural areas and municipal waste disposal from surrounding urban and sub-urban areas via open drains into the riverine ecosystem. Water quality guidelines and toxic equivalent factors highlighted the potential risk of low molecular weight PAHs to the aquatic life of the Chenab River. The flux estimated for PAHs contaminants from the Chenab River to the Indus River was >50 tons/year.  相似文献   
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Regional Environmental Change - Existing narratives and population projections of the global-scale Shared Socioeconomic Pathways (SSPs) do not capture regional differences in socioeconomic...  相似文献   
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After the tremendous accidents in European road tunnels over the past decade, many risk assessment methods have been proposed worldwide, most of them based on Quantitative Risk Assessment (QRA). Although QRAs are helpful to address physical aspects and facilities of tunnels, current approaches in the road tunnel field have limitations to model organizational aspects, software behavior and the adaptation of the tunnel system over time. This paper reviews the aforementioned limitations and highlights the need to enhance the safety assessment process of these critical infrastructures with a complementary approach that links the organizational factors to the operational and technical issues, analyze software behavior and models the dynamics of the tunnel system. To achieve this objective, this paper examines the scope for introducing a safety assessment method which is based on the systems thinking paradigm and draws upon the STAMP model. The method proposed is demonstrated through a case study of a tunnel ventilation system and the results show that it has the potential to identify scenarios that encompass both the technical system and the organizational structure. However, since the method does not provide quantitative estimations of risk, it is recommended to be used as a complementary approach to the traditional risk assessments rather than as an alternative.  相似文献   
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Agricultural activities are one of the major drivers of increased nutrient levels such as nitrogen (N) and phosphorus (P) to both terrestrial and aquatic ecosystems. Elevated nutrient concentrations are associated with degraded water quality that can result in potential impacts for human health and the environment. A recent European study has identified elevated concentrations of N and P for many European river monitoring stations. In many cases the management of N and P has been considered separately here we address the multi-dimensional issue of water quality where the simultaneous management and control of both N and P is considered desirable. Using an integrated modelling approach various nutrient management scenarios are examined. It is found that although the control of N and P involve different farm adjustments and induce different land use changes there is a certain degree of complementarity between these two nutrient controls. The policy implication of ignoring such complementarity is that the appropriate environmental taxes to control the required nutrient losses are overestimated, resulting in unnecessary welfare losses to the society.  相似文献   
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