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921.
- Sustainable chemistry - Section editors: Klaus Günter Steinhäuser, Steffi Richter, Petra Greiner, Jutta Penning, Michael AngrickBackground, Aim and Scope Recent developments in European chemicals policy, including the Registration, Evaluation and Authorization of Chemicals (REACH) proposal, provide a unique opportunity to examine the U.S. experience in promoting sustainable chemistry as well as the strengths and weaknesses of existing policies. Indeed, the problems of industrial chemicals and limitations in current regulatory approaches to address chemical risks are strikingly similar on both sides of the Atlantic. We provide an overview of the U.S. regulatory system for chemicals management and its relationship to efforts promoting sustainable chemistry. We examine federal and state and examine lessons learned from this system that can be applied to developing more integrated, sustainable approaches to chemicals management.Main Features There is truly no one U.S. chemicals policy, but rather a series of different un-integrated policies at the federal, regional, state and local levels. While centerpiece U.S. Chemicals Policy, the Toxic Substances Control Act of 1976, has resulted in the development of a comprehensive, efficient rapid screening process for new chemicals, agency action to manage existing chemicals has been very limited. The agency, however, has engaged in a number of successful, though highly underfunded, voluntary data collection, pollution prevention, and sustainable design programs that have been important motivators for sustainable chemistry. Policy innovation in the establishment of numerous state level initiatives on persistent and bioaccumulative toxics, chemical restrictions and toxics use reduction have resulted in pressure on the federal government to augment its efforts.Results and Conclusions It is clear that data collection on chemical risks and phase-outs of the most egregious chemicals alone will not achieve the goals of sustainable chemistry. These alone will also not internalize the cultural and institutional changes needed to ensure that design and implementation of safer chemicals, processes, and products are the focus of the future. Thus, a more holistic approach of ‘carrots and sticks’ – that involves not just chemical producers but those who use and purchase chemicals is necessary. Some important lessons of the US experience in chemicals management include: (1) the need for good information on chemicals flows, toxic risks, and safer substances.; (2) the need for comprehensive planning processes for chemical substitution and reduction to avoid risk trade-offs and ensure product quality; (3) the need for technical and research support to firms for innovation in safer chemistry; and (4) the need for rapid screening processes and tools for comparison of alternative chemicals, materials, and products.  相似文献   
922.
Riparian buffer zones can improve water quality and enhance habitat, but a comprehensive yet rapid method that can assist the resource manager in assessing the effectiveness of buffers is not available. The aim of this paper is to describe and illustrate the use of a newly developed field-based evaluation tool for riparian buffer zones in agricultural catchments. The Buffer Zone Inventory and Evaluation Form (BZIEF) incorporates criteria-based scoring systems developed from literature review, subsequent peer-review, and then a pilot field study. Use of the BZIEF is demonstrated by comparing buffer zones in three catchments established for water quality and habitat improvement under the Water Fringe Option agrienvironment scheme in England in order to assess whether the buffers were likely to provide environmental enhancement. Results among the three catchments were generally similar; buffer zones scored highly for their abundant vegetation cover, lack of erosion, stream habitat quality, and sufficient width. Furthermore, previous grassland or arable land use did not substantially affect buffer zone ratings. However, the BZIEF indicated that inappropriate soil characteristics in one catchment were likely to constrain buffer zone effectiveness for improving water quality. In another catchment, poor riparian vegetation diversity and structure may yield ineffective habitat enhancement, according to the BZIEF. It was concluded that the BZIEF might be a useful tool for buffer zone comparison and monitoring, even though more work is needed to test and validate the method. For example, the BZIEF could be used to target appropriate locations for buffer zones and is flexible, so could be adapted for different policies, objectives and regions.  相似文献   
923.
When ecosystems are threatened or scientific knowledge of the effects of human action is uncertain, legislative prohibition is often adopted. This paper examines how the criminalization of mangrove tree use affects ecosystem management outcomes. We explore the biological, economic and social sustainability effects of the legal ban on mangrove use on the coast of Bragança, Pará, north Brazil. There are two main categories of mangrove users in this area: firstly, local subsistence users who also derive some financial incomes from mangrove sale. Their mangrove use is intertwined with household livelihood strategies and they display self-initiated planning and action towards sustainable management; secondly, more mobile, purely commercial users who are responsible for most commercial mangrove exploitation and who employ regionally sequential, predatory resource exploitation strategies. These users are typically based at some distance from the exploited areas and share neither local livelihood strategies nor sustainability agendas. The current outright ban on any utilization of mangrove flora seems to undermine biological sustainability, is economically inefficient and generates normative insecurity, conflict and social polarization. The ineffectiveness of the outright legal prohibition of mangrove tree use in terms of sustainable coastal management leads us to investigate alternative management options. We suggest that the legalization of local mangrove utilization and the strengthening of local users rights and responsibilities to control outsiders in a co-management framework, as proposed in the Brazilian extractive reserves (RESEX) approach, is most likely to advance ecologically, economically and socially sustainable mangrove management. It is demonstrated that a legal recognition of local entitlements to mangrove trees would reduce social vulnerability and therefore move forest management outcomes into more desirable directions.
Marion GlaserEmail: Fax: +49-421-2380030
  相似文献   
924.
Integrated management and policy models suggest that solutions to environmental issues may be linked to the socioeconomic and political characteristics of a nation. In this study, we empirically explore these suggestions by applying them to the wetland management activities of nations. Structural equation modeling was used to evaluate a model of national wetland management effort and one of national wetland protection. Using five predictor variables of social capital, economic capital, environmental and political characteristics, and land-use pressure, the multivariate models were able to explain 60% of the variation in nations' wetland protection efforts based on data from 90 nations, as defined by level of participation in the international wetland convention. Social capital had the largest direct effect on wetland protection efforts, suggesting that increased social development may eventually lead to better wetland protection. In contrast, increasing economic development had a negative linear relationship with wetland protection efforts, suggesting the need for explicit wetland protection programs as nations continue to focus on economic development. Government, environmental characteristics, and land-use pressure also had a positive direct effect on wetland protection, and mediated the effect of social capital on wetland protection. Explicit wetland protection policies, combined with a focus on social development, would lead to better wetland protection at the national level.  相似文献   
925.
The New York Bight is perhaps one of the most used and abused coastal areas in the world as a consequence of urbanization and the disposal of the waste of some 20 million people who reside by its shores and surrounding bays and estuaries. A variety of sources, including those associated with sewage wastes, industrial wastes, contaminated dredged material, urban runoff, and atmospheric fallout contaminate these coastal waters. Many of the stresses of excess population and industrialization as measured by pollutant loadings and ecosystem impacts can be crudely quantified in terms of use impairments-use impairments that have measurable social and economic relevance. Five broad categories of impairment attributed to pollution in the Bight that are causing significant losses of ecological, economic, or social values are: beach closures, unsafe seafoods, hazards to commercial and recreational navigation, loss of commercial and recreational fisheries, and declines in birds, mammals and turtles. These impairments are generally caused by floatable wastes, nutrients, toxicants, pathogens and habitat loss. Measures of such impairments are not standard, nor in many cases totally quantifiable. We have examined specific subsets of these impairments in terms of their spatial and temporal changes and as a first approximation determined the economic and social significance of these changes. the cost of these impaired uses of the Bight are measured in terms of billions of dollars annually for New York and New Jersey.  相似文献   
926.
This article attempts to analyse the social interface between formal institutions and local fishing communities along the Pamba‐Achankovil River Basin in Kerala, India. It examines primarily the nature of the relationship between state agencies and traditional fishing communities in the context of (i) enforcing certain formal regulations of resource use and (ii) implementing resource enhancement programmes. The article also analyses the nature of social interfaces that emerge when local level formal organizations, such as cooperatives and gram panchayats, take up resource management or community welfare schemes on behalf of the traditional fisherfolk in the study region. Social interfaces can be understood in terms of social processes, such as cooperation, accommodation and conflicts between various actors involved in fisheries management. The article is based on ethnographic fieldwork. Interview guides and focus group discussions were the primary tools of data collection. The findings show that the relationships between formal institutions and traditional riverine fishing communities lack mutual trust. Conflicts between fishing communities and state agencies emerge when the formal institutions threaten or contradict those elements of local culture that sustain livelihood needs. Conflicts and discontent with a particular formal institution can also lead to the modification or violation of coexisting institutional arrangements.  相似文献   
927.
Residential mobility and personal well-being   总被引:1,自引:0,他引:1  
This research examines the relationship between personal mobility rate (number of lifetime moves/respondent's age) and health status. A contextual analysis is proposed in which the health consequences of relocation depend not only on the immediate circumstances surrounding a move, but also on the broader context of the individual's residential history, current life situation, and aspirations for the future. Two hundred and forty-two adult employees completed an initial survey of lifetime residential history, current residential desirability, employment experience, and perceived housing options for the future. Three months later, a panel group of 121 respondents completed a follow-up survey of emotional and physical well-being. Frequent relocation was directly associated with a greater number of illness-related symptoms, but the impact of mobility rate was largely mediated by psychological factors. Health problems were more prevalent among high-mobility individuals characterized by low rather than high levels of environmental exploratory tendency; among low-mobility persons reporting low versus high levels of residential choice and congruence; and among low residential-quality individuals who perceived future residential options to be unavailable rather than available.  相似文献   
928.
The paper analyses the costs and benefits of conserving wildlife and reports part of a wider research project which aims to estimate the benefits of certain ecological types and habitats, and to compare the outcome of different techniques used to value wildlife. The authors outline a range of philosophical, technical and methodological problems in deriving cardinal measures of costs and benefits.  相似文献   
929.
Environmentalism and elitism: a conceptual and empirical analysis   总被引:2,自引:0,他引:2  
The frequent charge that environmentalism is elitist is examined conceptually and empirically. First, the concept of elitism is analyzed by distinguishing between three types of accusations made against the environmental movement: (a)compositional elitism suggests that environmentalists are drawn from privileged socioeconomic strata, (b)ideological elitism suggests that environmental reforms are a subterfuge for distributing benefits to environmentalists and/or costs to others, and (c)impact elitism suggests that environmental reforms, whether intentionally or not, do in fact have regressive social impacts.The evidence bearing on each of the three types of elitism is examined in some detail, and the following conclusions are drawn: Compositional elitism is an exaggeration, for although environmentalists are typically above average in socioeconomic status (as are most sociopolitical activists), few belong to the upper class. Ideological elitism may hold in some instances, but environmentalists have shown increasing sensitivity to equity concerns and there is little evidence of consistent pursuit of self-interest. Impact elitism is the most important issue, and also the most difficult to assess. It appears that there has been a general tendency for environmental reforms to have regressive impacts. However, it is increasingly recognized that problems such as workplace pollution and toxic waste contamination disproportionately affect the lower socioeconomic strata, and thus reforms aimed at such problems will likely have more progressive impacts.This is Michigan Agricultural Experiment Station Journal article no. 11508.  相似文献   
930.
高压水射流清洗机清洗质量的FUZZY评价   总被引:3,自引:0,他引:3  
根据模糊集的基本理论,构造了一个评价高压水射流清洗机清洗质量的数学模型,并给出了模糊评价应用范例。  相似文献   
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