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871.
Paul Ekness Timothy Randhir 《Journal of the American Water Resources Association》2007,43(6):1468-1482
Abstract: Spatio‐temporal linkages between hydrologic and ecologic dimensions of watersheds play a critical role in conservation policies. Habitat potential is influenced by variation along longitudinal and lateral gradients and land use disturbance. An assessment of these influences provides critical information for protecting watershed ecosystems and in making spatially explicit, conservation decisions. We use an ecohydrologic approach that focuses on interface between hydrological and ecological processes. This study focuses on changes in watershed habitat potentials along lateral (riparian), and longitudinal (stream order) dimensions and disturbance (land use). The habitat potentials were evaluated for amphibians, reptiles, mammals, and birds in the Westfield River Watershed of Massachusetts using geographic information systems and multivariate analysis. We use a polynomial model to study nonlinear effects using robust regression. Various spatial policies were modeled and evaluated for influence on species diversity. All habitat potentials showed a strong influence along spatial dimensions and disturbance. The habitat potential for all vertebrate groups studied decreased as the distance from the riparian zone increased. Headwaters and lower order subwatersheds had higher levels of species diversity compared to higher order subwatersheds. It was observed that locations with the least disturbance also had higher habitat potential. The study identifies three policy criteria that could be used to identify critical areas within a watershed to conserve habitat suitable for various species through management and restoration activities. A spatially variable policy that is based on stream order, riparian distance, and land use can be used to maximize watershed ecological benefits. Wider riparian zones with variable widths, protection of headwaters and lower order subwatersheds, and minimizing disturbance in riparian and headwater areas can be used in watershed policy. These management objectives could be achieved using targeted economic incentives, best management practices, zoning laws, and educational programs using a watershed perspective. 相似文献
872.
Celina Ramjoué 《Journal of Agricultural and Environmental Ethics》2007,20(5):419-436
The regulatory structures underlying United States and European Union policies regarding genetically modified (GM) food and crops are fundamentally different. The US regulates GM foods and crops as end products, applying roughly the same regulatory framework that it does to non GM foods or crops. The EU, on the other hand, regulates products of agricultural biotechnology as the result of a specific production process. Accordingly, it has developed a network of rules that regulate GM foods and crops specifically. As a result, US regulation of GM foods and crops is relatively permissive, whereas EU regulation is relatively restrictive. Why are genetically modified food policies in the United States and the European Union so strikingly different? In the light of the recent World Trade Organization dispute on agricultural biotechnology, it may seem that economic interests are the driving force behind policies. While they are certainly part of the picture, the issue is far more complex. This paper argues that three different elements help explain differences between US and EU GM food policies. First, an investigation of US and European policies of the 1970s and 1980s on recombinant DNA research and of events leading up to early GM food and crop regulation allows a deeper understanding of current policy. Second, scrutinizing underlying values and norms can uncover the beliefs that condition current GM food and crop policy. Third, an analysis of involved actors’ views and levels of success in influencing policy is essential to understanding US and EU policies. 相似文献
873.
The traditional vision of the role science should play in policy making is of a two stage process of scientists first finding
out the facts, and then policy makers making a decision about what to do about them. We argue that this two stage process
is a fiction and that a distinction must be drawn between pure science and science in the service of public policy. When science
is transferred into the policy realm, its claims to truth get undermined because we must abandon the open-ended nature of
scientific inquiry. When we move from the sphere of science to the sphere of policy, we pick an arbitrary point in the open-ended
scientific process, and ask our experts to give us the answer. The choice of the endpoint, however, must always be arbitrary
and determined by non-scientific factors. Thus, the two stages in the model of first finding the facts, and then making a
decision about what to do, cannot be clearly separated. The second stage clearly affects the first. This conclusion will have
implications about existing scientific policy institutions. For example, we advocate that the environmental assessment process
be radically overhauled, or perhaps even let go. It will be our position that ultimately a better model for the involvement
of scientists in public policy debates is that of being participants in particular interest groups (“hired guns”), rather
than as supposedly unbiased consultants to decision-makers. 相似文献
874.
Chemical Characteristics of Urban Stormwater Sediments and Implications for Environmental Management, Maricopa County, Arizona 总被引:2,自引:0,他引:2
On the basis of published guidelines, urban stormwater sediments do not appear to constitute a major regional environmental
problem with respect to the chemical characteristics investigated here. At individual sites, high concentrations of organic
compounds—chlordane, dieldrin, PCBs, and toxaphene—may require some attention. The possible environmental hazard presented
by low-level organochlorine contamination is not addressed in this paper; however, high levels of toxicity in urban sediments
are difficult to explain. Sediment toxicity varied significantly with time, which indicates that these tests should be evaluated
carefully before they are used for management decisions. 相似文献
875.
In recent years, Turkey has experienced rapid economic and population growth coupled with both an equally rapid increase in
energy consumption and a vast disparity in welfare between socioeconomic groups and regions. In turn, these pressures have
accelerated the destruction of productive, assimilative, and regenerative capacities of the ecosystems, which are essential
for the well-being of the people and the economy. This paper describes the structure and function of major ecosystem types
in Turkey and discusses the underlying causes of environmental degradation in the framework of economy, energy, environment,
and ethics. From a national perspective, this paper suggests three sustainability-based policies necessary for Turkey's long-term
interests that balance economic, environmental, and energy goals: (1) decoupling economic growth from energy consumption growth
through the development of energy-efficient and renewable energy technologies; (2) linking economic efficiency and distributive
justice of wealth and power through distributive and participatory public policies; and (3) integrating the economic and ecological
systems through the internalization of externalities and ecosystem rehabilitation. 相似文献
876.
Kaufman MM 《Environmental management》2000,26(1):89-97
/ To test the effectiveness of Michigan's soil erosion control law, 30 construction sites were evaluated in the east-central part of the state. The analytical framework lumped nine best management practices (BMPs) most closely related to the law into three categories: slope stabilization, soil stabilization, and water management. All sites were in the land clearing or foundation/framing stage of construction and were evaluated within 2 days after a rainfall event. Only four of the sites performed above the mean of the scoring scale, with the categorical scoring of BMPs indicating the worst performance for slope stabilization measures. The poor results suggest a failure to integrate scientific knowledge of erosion control with policy. A fundamental problem is the lack of basic site data on soil, topography, and hydrology, resulting in the incorrect application of BMPs, such as staging, filter fences, and berms. The current institutional framework for soil erosion control also provides disincentives to mitigate local erosion problems. 相似文献
877.
Minimal models and agroecological policy at the regional scale: An application to salinity problems in southeastern Australia 总被引:2,自引:0,他引:2
John M. Anderies 《Regional Environmental Change》2005,5(1):1-17
A minimal dynamical systems model that couples agricultural activity, native vegetation, and hydrological processes is developed to explore policy options regarding regional-scale soil and water salinization in southeastern Australia. The analysis suggests that although considerable revegetation is required to restore catchment water balance, the current value of water in uses other than agriculture is too low for revegetation to be economically viable. In contrast, groundwater pumping generates significant short-term gains by preventing soil salinization but is not a viable long-term solution. Thus, effective salinity management policy must include mechanisms to increase the value of water in uses other than irrigated agriculture to achieve sufficient long-term revegetation. These results are robust over a wide range of parameter values and thus provide a basis for policy action in the face of uncertainty about groundwater flow characteristics. 相似文献
878.
冯德清 《中国安全生产科学技术》2006,2(4):65-69
在安全管理越来越得到重视的今天,安全责任追究力度越来越大,政府和官员对安全管理更多倾向于采取自我保护式的高压和严惩。这种管理模式在各方利益主体的博弈下,使得安全管理的目标与结果产生变异,甚至会产生不愿看到的结果。事实上安全管理制度运行的成本是巨大的,单靠严惩是不能解决问题的。本文运用博弈理论、新制度经济学、信息经济学、机制设计理论等经济学方法,对安全管理的运行机制进行分析,认为安全管理必须理性预防,堵疏结合,通过设计符合客观规律的安全管理运行机制,方能确保安全生产。 相似文献
879.
污水处理行业的技术经济特性决定了污水处理行业政府规制的必要性.明确的规制目标是建立污水处理行业政府规制体制的基本前提.在详细分析了污水行业技术经济特性的基础上,提出了当前污水处理行业政府规制目标,并结合当前污水处理行业政府规制现状,做了相关政策的分析研究,为政府监管规制建设做了有益的探索. 相似文献
880.
Franck L. B. Meijboom Tatjana Visak Frans W. A. Brom 《Journal of Agricultural and Environmental Ethics》2006,19(5):427-442
The many well-publicized food scandals in recent years have resulted in a general state of vulnerable trust. As a result, building consumer trust has become an important goal in agri-food policy. In their efforts to protect trust in the agricultural and food sector, governments and industries have tended to consider the problem of trust as merely a matter of informing consumers on risks. In this article, we argue that the food sector better addresses the problem of trust from the perspective of the trustworthiness of the food sector itself. This broad idea for changing the focus of trust is the assumption that if you want to be trusted, you should be trustworthy. To provide a clear understanding of what being trustworthy means within the food sector, we elaborate on both the concept of trust and of responsibility. In this way we show that policy focused on enhancing transparency and providing information to consumers is crucial, but not sufficient for dealing with the problem of consumer trust in the current agri-food context. 相似文献