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111.

India and Canada share a common heritage in natural resources management. Both have a colonial background, settlers and indigenous peoples; there is a history of management agencies with utilitarian attitudes, and a history of treating public lands as commodities for commerce rather than as resources for local livelihoods. This historical context guided the overall goal of this study, which was policy development for the sustainable use of mountain environments. Interviews, workshops and seminars were held with local people and resource management professionals in a comparative case study in two regions; the Kullu area in Himachal Pradesh, India and the Arrow Lakes area in British Columbia, Canada. The paper is organized around two main objectives of the work relating to the successes and failures of mountain environment resource management policies and the development of criteria for assessing and monitoring sustainability in mountain environments, in particular, criteria for examining relevant crosscultural dimensions of sustainable development in these environments. By way of conclusion the paper considers further ways in which traditional resource policy development and implementation is being challenged by changing values and priorities; ecosystems management with people; and co-management and public participation.  相似文献   
112.
Challenges to interdisciplinary research in ecosystem-based management   总被引:1,自引:0,他引:1  
Despite its necessity, integration of natural and social sciences to inform conservation efforts has been difficult. We examined the views of 63 scientists and practitioners involved in marine management in Mexico's Gulf of California, the central California coast, and the western Pacific on the challenges associated with integrating social science into research efforts that support ecosystem-based management (EBM) in marine systems. We used a semistructured interview format. Questions focused on how EBM was developed for these sites and how contextual factors affected its development and outcomes. Many of the traditional challenges linked with interdisciplinary research were present in the EBM projects we studied. However, a number of contextual elements affected how mandates to include social science were interpreted and implemented as well as how easily challenges could be addressed. For example, a common challenge is that conservation organizations are often dominated by natural scientists, but for some projects it was easier to address this imbalance than for others. We also found that the management and institutional histories that came before EBM in specific cases were important features of local context. Because challenges differed among cases, we believe resolving challenges to interdisciplinary research should be context specific.  相似文献   
113.
Despite the vast amount of research on threatened and endangered green turtle populations, some uncertainty regarding stage durations, growth rates, and age at maturation remains. We used skeletochronology to address this gap in knowledge for green turtle populations in the North Atlantic Ocean that use coastal waters along the southeastern U.S. as developmental habitat. Oceanic stage duration was estimated at 1–7 years ( [`(\textX)] \overline{\text{X}}  = 3 years). Several growth models, including von Bertalanffy, logistic, Gompertz, and power functions were evaluated for describing sex-specific length-at-age data. Ages at maturation estimated using mean size at nesting for females from each genetic sub-population contributing juveniles to this neritic foraging area were 44 years (Florida), 42.5 years (Costa Rica), and 42 years (Mexico), which were higher than previously reported ages. This implies that nesting populations comprising primarily individuals utilizing foraging grounds in the southeastern U.S. may take longer to recover than previously estimated.  相似文献   
114.
The photovoice research project, “At the water's edge”, which gives voice to communities exploring the threats and impact of climate change and rising sea levels on coastal communities, was conducted during an environmental art symposium in the Noosa Biosphere Reserve, Australia in June 2009. Photos by participants illustrated both local and global threats and reflected psychological tension between global and local action. This research partnership with the local people demonstrated an innovative visualisation technique which can be used to collaboratively build capacity and consensus about adaptation to climate change. It also contributed to the Biosphere Reserve's educational and cultural aims in relation to climate change.  相似文献   
115.
The impacts of strategically located contour prairie strips on sediment and nutrient runoff export from watersheds maintained under an annual row crop production system have been studied at a long-term research site in central Iowa. Data from 2007 to 2011 indicate that the contour prairie strips utilized within row crop-dominated landscapes have greater than proportionate and positive effects on the functioning of biophysical systems. Crop producers and land management agencies require comprehensive information about the Best Management Practices with regard to performance efficacy, operational/management parameters, and the full range of financial parameters. Here, a farm-level financial model assesses the establishment, management, and opportunity costs of contour prairie strips within cropped fields. Annualized, depending on variable opportunity costs the 15-year present value cost of utilizing contour prairie strips ranges from $590 to $865 ha?1 year?1 ($240–$350 ac?1 year?1). Expressed in the context of “treatment area” (e.g., in this study 1 ha of prairie treats 10 ha of crops), the costs of contour prairie strips can also be viewed as $59 to about $87 per treated hectare ($24–$35 ac?1). If prairie strips were under a 15-year CRP contract, total per acre cost to farmers would be reduced by over 85 %. Based on sediment, phosphorus, and nitrogen export data from the related field studies and across low, medium, and high land rent scenarios, a megagram (Mg) of soil retained within the watershed costs between $7.79 and $11.46 mg?1, phosphorus retained costs between $6.97 and $10.25 kg?1, and nitrogen retained costs between $1.59 and $2.34 kg?1. Based on overall project results, contour prairie strips may well become one of the key conservation practices used to sustain US Corn Belt agriculture in the decades to come.  相似文献   
116.
Crop and livestock losses to wildlife are a concern for people neighboring many protected areas (PAs) and can generate opposition to conservation. Examining patterns of conflict and associated tolerance is important to devise policies to reduce conflict impacts on people and wildlife. We surveyed 398 households from 178 villages within 10 km of Ranthambore, Kanha, and Nagarahole parks in India. We compared different attitudes toward wildlife, and presented hypothetical response scenarios, including killing the problem animal(s). Eighty percent of households reported crop losses to wildlife and 13 % livestock losses. Higher crop loss was associated with more cropping months per year, greater crop variety, and more harvest seasons per year but did not vary with proximity to the PA, suggesting that PAs are not necessarily “sources” for crop raiders. By contrast, complaints of “depredating carnivores” were associated with people-grazing animals and collecting resources from PAs. Many households (83 %) engaged in mitigation efforts. We found that only fencing and guard animals reduce crop losses, and no efforts to lower livestock losses. Contrary to our expectations, carnivores were not viewed with more hostility than crop-raiding wildlife. Households reported greater inclination to kill herbivores destroying crops or carnivores harming people, but not carnivores preying on livestock. Our model estimated crop loss was 82 % across surveyed households (highest in Kanha), while the livestock loss experienced was 27 % (highest in Ranthambore). Our comparative study provides insights into factors associated with conflict loss and tolerance, and aids in improving ongoing conservation and compensation efforts.  相似文献   
117.
In contrast to an open environment where a specific celestial cue is predominantly used, visual contrast of canopies against the sky through the gap, known as canopy cues, is known to play a major role for visually guided insect navigators in woodland habitats. In this paper, we investigated whether a subsocial shield bug, Parastrachia japonensis, could gauge direction using canopy cues on a moonless night. The results show that they could perform the round trip foraging behaviour even in an experimental arena with only an artificial round gap opened in the ceiling of the arena and adjust their homing direction for a new azimuth when the gap was rotated. Thus, P. japonensis can use slightly brighter canopy cues as a compass reference but not complex landmarks during nocturnal homing behaviour.  相似文献   
118.
Applying 3DCE to environmentally responsible manufacturing practices   总被引:1,自引:0,他引:1  
A review of recent literature in the fields of operations, supply chain, and management indicates there is on-going interest in improving new product development (NPD) performance. Three-dimensional concurrent engineering (3DCE), the simultaneous design of product, process and supply chain have been proposed as a way to improve traditional NPD outcomes, such as reduced time to market, lower costs, and improved customer acceptance. There appears to be a lesser concern associated with the environmental impacts of new products. Environmentally responsible manufacturing (ERM) on new product development focuses on reduced emissions, hazardous materials elimination, and lower product weight without sacrificing functionality. This paper explores the following issue: will employing 3DCE to integrate NPD and ERM yield better benefits than the separate and uncoordinated application of environmental goals and NPD initiatives?  相似文献   
119.
Because of the similarities in European and North American dietary exposure, it has been suggested that the order of magnitude higher body burdens in North Americans may be due to international variations in exposure via ingestion of indoor dust. Furthermore, ingestion of indoor dust has been suggested as a possible source of PBDEs in the blood serum of New Zealanders. Hence, polybrominated diphenyl ethers (PBDEs) were measured in domestic indoor dust from: Amarillo/Austin, Texas, US; Birmingham, UK; Toronto, Canada; and Wellington, New Zealand. Concentrations of BDE 209 in two UK samples were - at 520,000 and 100,000 ng g(-1) - the highest ever recorded in a domestic (or office) indoor dust sample. Median concentrations in ng g(-1) were: in Canada 620 and 560 for Sigmatri-hexa-BDEs and BDE 209 respectively; in New Zealand 96, BDE 209 not determined; in the UK 59 and 2,800; and in the US 1600 and 1300. With respect to BDE 209, concentrations were in the order: UK approximately US>Canada. For Sigmatri-hexa-BDEs, the order of concentrations was US approximately Canada>New Zealand approximately UK. Combined with principal component analysis of congener patterns, this suggests that, while North American dusts are contaminated by both Deca- and Penta-BDE commercial formulations, UK dusts are contaminated predominantly by Deca-BDE. The Octa-BDE formulation appears of minimal importance in accordance with available market demand figures. Despite the commercial formulations of PBDEs never having been manufactured in, nor imported into New Zealand, their presence in dusts from that country suggests international trade in PBDE-containing goods is an important pathway effecting their global distribution.  相似文献   
120.
Whether information and communication technology (ICT) constitutes a threat or a cure to environment??s deterioration is controversially discussed. Empirical evidence on the impacts of ICT is rare, so that generalizable lessons can hardly be drawn. This study provides empirical results on the role of ICT in research for environmental sustainability, but instead of ascertaining the impact of ICT on environmental protection, we conduct an analysis of the use of ICT in sustainability research. We assess the preferences of experts in different thematic sustainability fields for applying ICT tools, and we investigate ways to improve the application of these tools in order to augment their returns with respect to environmental protection research. This analysis is based on a set of surveys that were administered to international experts to evaluate the importance of ICT in environmental sustainability research and the research demands in key environmental sectors, such as climate change, natural resources, energy and biodiversity. The methodological framework is built on the analysis of users?? preferences for future developments in ICT tools using stated preferences techniques. Overall results suggest that ICT tools need to be developed in specific contexts, taking into account users?? needs and expectations. Our analysis shows that the use of ICT in environmental research is of great importance in the scientific community, but it can also play a crucial role in the policy context.  相似文献   
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