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1.
Effective management refers to the ability of a protected area or indigenous territory to meet its objectives, particularly as they relate to the protection of biodiversity and forest cover. Effective management is achieved through a process of consolidation, which among other things requires legally protecting sites, integrating sites into land‐use planning, developing and implementing management and resource‐use plans, and securing long‐term funding to pay for recurrent costs. Effectively managing all protected areas and indigenous territories in the Amazon may be needed to avoid a deforestation tipping point beyond which regional climatic feedbacks and global climate change interact to catalyze irreversible drying and savannization of large areas. At present, protected areas and indigenous territories cover 45.5% (3.55 million km2) of the Amazon, most of the 60–70% forest cover required to maintain hydrologic and climatic function. Three independent evaluations of a long‐term large‐scale philanthropic initiative in the Amazon yielded insights into the challenges and advances toward achieving effective management of protected areas and indigenous territories. Over the life of the initiative, management of sites has improved considerably, particularly with respect to management planning and capacity building, but few sites are effectively managed and many lack sufficient long‐term financing, adequate governance, support of nongovernmental organizations, and the means to withstand economic pressures. The time and money required to complete consolidation is still poorly understood, but it is clear that philanthropic funding is critical so long as essential funding needs are not met by governments and other sources, which could be on the order of decades. Despite challenges, it is encouraging that legal protection has expanded greatly and management of sites is improving steadily. Management of protected areas in other developing countries could be informed by improvements that have occurred in Amazonian countries.  相似文献   
2.
Following the renewed effort at achieving a new green revolution for Africa, emphasis has been placed on modernizing smallholder agriculture through the deployment of improved inputs especially mechanized technologies. In Ghana, the government has in the last decade emphasized the provision of subsidized mechanized ploughing services to farmers alongside a rapidly growing private sector tractor service market. While mechanized technology adoption rates have increased rapidly, the deployment of these technologies has been without critical analysis of the impacts on production patterns and local agrarian systems. This paper examines the distributional impacts of agriculture mechanization on cropping patterns and farm sizes of smallholder farmers in northern Ghana using Geographic Information Systems (GIS) techniques, and semi-structured interviews with smallholder farmers (n=60). Specifically, comparative analysis of the field sizes and cropping patterns of participant farmers prior to and after the adoption of mechanized technologies was conducted. In-depth interviews were used to contextualize the experiences of smallholder farmers toward understanding how mechanization may be impacting traditional agriculture. Our findings reveal a mechanization paradox in which farm sizes are expanding, while cropping patterns are shifting away from traditional staple crops (pearl millet and sorghum bicolor) to market-oriented crops (maize, rice and groundnuts). This transition we argue, has adverse implications on the cultural dimension of food security, the organization of social life, and climate change adaptation. We recommend a retooling of the current agricultural policy focus to ensure context sensitivity for a more robust battle against food insecurity.  相似文献   
3.
Visibility degradation, one of the most noticeable indicators of poor air quality, can occur despite relatively low levels of particulate matter when the risk to human health is low. The availability of timely and reliable visibility forecasts can provide a more comprehensive understanding of the anticipated air quality conditions to better inform local jurisdictions and the public. This paper describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada’s operational Regional Air Quality Deterministic Prediction System (RAQDPS) for the Lower Fraser Valley of British Columbia. A baseline model (GM-IMPROVE) was constructed using the revised IMPROVE algorithm based on unprocessed forecasts from the RAQDPS. Three additional prototypes (UMOS-HYB, GM-MLR, GM-RF) were also developed and assessed for forecast performance of up to 48 hr lead time during various air quality and meteorological conditions. Forecast performance was assessed by examining their ability to provide both numerical and categorical forecasts in the form of 1-hr total extinction and Visual Air Quality Ratings (VAQR), respectively. While GM-IMPROVE generally overestimated extinction more than twofold, it had skill in forecasting the relative species contribution to visibility impairment, including ammonium sulfate and ammonium nitrate. Both statistical prototypes, GM-MLR and GM-RF, performed well in forecasting 1-hr extinction during daylight hours, with correlation coefficients (R) ranging from 0.59 to 0.77. UMOS-HYB, a prototype based on postprocessed air quality forecasts without additional statistical modeling, provided reasonable forecasts during most daylight hours. In terms of categorical forecasts, the best prototype was approximately 75 to 87% correct, when forecasting for a condensed three-category VAQR. A case study, focusing on a poor visual air quality yet low Air Quality Health Index episode, illustrated that the statistical prototypes were able to provide timely and skillful visibility forecasts with lead time up to 48 hr.

Implications: This study describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada’s operational Regional Air Quality Deterministic Prediction System. The main applications include tourism and recreation planning, input into air quality management programs, and educational outreach. Visibility forecasts, when supplemented with the existing air quality and health based forecasts, can assist jurisdictions to anticipate the visual air quality impacts as perceived by the public, which can potentially assist in formulating the appropriate air quality bulletins and recommendations.  相似文献   

4.
The figure of the Health and Safety Coordinator (HSC), as a necessary and competent engineer in the construction sector, emerged in Spain on December 25, 1997 as a result of the implementation of European Directive 92/57/EEC. The coming of age of this figure is a sufficient period of time for determining its implementation and impact within the construction sector. The research carried out in this article arose from the analysis of statistical data obtained through Public Authorities and Professional Bodies. The quantitative study of the data extracted is complemented by the creation of specific benchmark indicators which connect four fundamental variables in the construction industry: the number of accidents, volume of workers employed, building units, and health and safety coordination posts. Furthermore, the legislation governing the HSC engineer in each of the 28 Member States of the European Union is studied. The results show a high implementation rate for the figure of the HSC, as well as a positive impact in relation to the reduced accident rate in the construction sector. Likewise, an update to the procedures of the various authorities is considered to be necessary in order to make the data concerning the actual work of the health and safety coordinators public. Finally, a review of the Spanish legislation concerning the HSC Coordinator is considered to be inevitable, in order to bring it up to the levels of professional skill and competence defined by the majority of European Union Member States.  相似文献   
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6.
Firms engaged in industrial ecology hope to reduce environmental impacts and costs, improve resource efficiency, and create symbiotic relationships that reduce transaction costs and enhance information flow. However, current LCA tools do not explain firms' incentives to implement the principles of industrial ecology, or how an individual or firm can affect the products and processes at other firms. Game theory, on the other hand, allows investigation of the willingness of producers and consumers to seek strategies that promote the common interest of the system while not harming their own interests. This paper applies game theory to the lifecycle of bottle packaging, and presents a framework for analysis of the choice between refillable and disposable bottles. Although refillable bottles may be more cost effective in the long run, bottlers only have incentive to use refillable bottles when they are sure that consumer return rates will be reasonably high. It has been found that consumers who keep or dispose of refillable bottles, or respond to deposit/refund return incentives by reducing their demand, may drive costs up and encourage adoption of disposables. A simple model is provided which finds the optimal bottler strategy as a function of the bottler's expectations for consumer cooperation.  相似文献   
7.
8.
T. Ikeda 《Marine Biology》1992,113(2):313-318
The fate of the polycyclic aromatic hydrocarbon [3H]benzo[a]pyrene (BaP) was examined in two species of scleractinian corals, Favia fragum (Esper) and Montastrea annularis (Ellis and Solander), which were collected in the patch reefs surrounding Alina's Reef (25°23.25N; 80°09.8W) in Biscayne National Park, Florida, USA, in July, 1990. Corals were exposed to initial concentrations of 5 g/l in a simple static system for 25 h. BaP uptake was estimated from the disappearance of BaP from the water. Uptake rates were 6.5±0.7 and 10.8±0.2 g BaP cm-2h-1 for F. fragum and M. annularis, respectively, at initial BaP concentrations and were directly proportional to the concentration of BaP in the water. The separation of zooxanthellae from coral tissue revealed that zooxanthellae can accumulate up to 53 and 64% of the total BaP-derived radioactivity present in F. fragum and M. annularis, respectively. Both corals metabolized BaP slowly, as most of the accumulated radioactivity was present as the unmetabolized chemical. However, aqueous and organic-soluble metabolites were found in both the animal and zooxanthellae fractions. Analysis by high-performance liquid chromatography (HPLC) revealed that both species of corals metabolized BaP to various tetrols, triols, dihydrodiols, quinones and phenols, although the pattern of metabolites differed between species. Zooxanthellae contained some of the same Phase I metabolites found in the animal tissue; however, tetrols and triols were absent in extracts from the zooxanthellae. The elimination of BAP from corals was also slow; approximately 38 and 65% of the accumulated radioactivity was still present in F. fragum and M. annularis, respectively, 144 h following the transfer of exposed corals to an uncontaminated flow-through seawater system.  相似文献   
9.
In 1991, a collaborative project to revise the terrestrial component of a national ecological framework was undertaken with a wide range of stakeholders. This spatial framework consists of multiple, nested levels of ecological generalization with linkages to existing federal and provincial scientific databases. The broadest level of generalization is the ecozone. Macroclimate, major vegetation types and subcontinental scale physiographic formations constitute the definitive components of these major ecosystems. Ecozones are subdivided into approximately 200 ecoregions which are based on properties like regional physiography, surficial geology, climate, vegetation, soil, water and fauna. The ecozone and ecoregion levels of the framework have been depicted on a national map coverage at 1:7 500 000 scale. Ecoregions have been subdivided into ecodistricts based primarily on landform, parent material, topography, soils, waterbodies and vegetation at a scale (1:2 000 000) useful for environmental resource management, monitoring and modelling activities. Nested within the ecodistricts are the polygons that make up the Soil Landscapes of Canada series of 1:1 000 000 scale soil maps. The framework is supported by an ARC-INFO GIS at Agriculture Canada. The data model allows linkage to associated databases on climate, land use and socio-economic attributes.  相似文献   
10.
This paper argues on both theoretical and empirical grounds that, beyond a certain point, there is an unavoidable conflictbetween economic development (generally taken to mean 'materialeconomic growth') and environmental protection. Think for a moment of natural forests, grasslands, marine estuaries, salt marshes, and coral reefs; and of arable soils, aquifers, mineraldeposits, petroleum, and coal. These are all forms of 'natural capital' that represent highly-ordered self-producing ecosystemsor rich accumulations of energy/matter with high use potential (low entropy). Now contemplate despoiled landscapes, eroding farmlands, depleted fisheries, anthropogenic greenhouse gases,acid rain, poisonous mine tailings and toxic synthetic compounds.These all represent disordered systems or degraded forms of energy and matter with little use potential (high entropy). The main thing connecting these two states is human economic activity. Ecological economics interprets the environment-economyrelationship in terms of the second law of thermodynamics. The second law sees economic activity as a dissipative process. Fromthis perspective, the production of economic goods andservices invariably requires the consumption of available energy and matter. To grow and develop, the economynecessarily 'feeds' on sources of high-quality energy/matter first produced by nature. This tends to disorder and homogenizethe ecosphere, The ascendance of humankind has consistently been accompanied by an accelerating rate of ecological degradation, particularly biodiversity loss, the simplificationof natural systems and pollution. In short, contemporary political rhetoric to the contrary, the prevailing growth-oriented global development paradigm is fundamentally incompatible with long-term ecological and social sustainability. Unsustainability is not a technical nor economic problem as usually conceived, but rather a state of systemic incompatibilitybetween a economy that is a fully-contained, growing, dependent sub-system of a non-growing ecosphere. Potential solutions fly inthe face of contemporary development trends and cultural values.  相似文献   
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