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561.
山东省生物多样性保护进展 总被引:1,自引:0,他引:1
分析了山东省生物多样性现状及国家重点保护动植物物种保护状况,论述了自然保护区、森林公园和风景名胜区建设与管理特征,指出了外来物种入侵和生物多样性保护存在的问题。 相似文献
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563.
The debate over snowmobiling and other types of motorized recreation in US national parks signals the need for a better understanding of the meanings of these experiences. The fundamental issue facing many parks is whether snowmobiling is an appropriate activity. The matter of appropriateness is anchored in two questions: (1) Does snowmobiling in national parks cause unacceptable biophysical and social impacts? (2) Are snowmobiling experiences consistent with the fundamental purposes of national parks? This article particularly addresses the appropriateness issue and presents the findings of an interpretive study of the meanings of snowmobiling experiences in Yellowstone National Park (YNP). Sixty-five semistructured interviews were conducted with winter visitors who used snowmobiles in the park during the winter season of 1999. Overall, the study findings reveal that visitors on snowmobiles view YNP as a place to experience its wildland attributes, such as natural scenery, geothermal features, and, especially, wildlife. Snowmobiling is perceived as a mode of transportation rather than the experience in and of itself. The results challenge the popular image of snowmobiles as thrill-craft and snowmobilers as thrill-seekers. The study demonstrates that snowmobiling in YNP affords highly meaningful recreational experiences, grounded in appreciating the park’s unique natural features and attributes. 相似文献
564.
A Forest Planning Language and Simulator (FORPLAN) has been developed to facilitate the use of simulation for integrating fire into the land management planning process.FORPLAN incorporates unique characteristics of previous systems, links numerous models and data bases, allows selection of variable resolution levels, and permits discrete time simulation of disturbances on plants, fuels, and animals. No previous computer experience is required of the user, sinceFORPLAN recognizes simple English words and phrases. 相似文献
565.
D. L. Anderson P. C. Rosendahl 《Journal of the American Water Resources Association》1998,34(2):235-249
ABSTRACT: South Florida and the Everglades have been under intensive development since 1850 by Federal and State governments who encouraged and financed extensive drainage and hydraulic changes, primarily for agricultural settlement. Agricultural development of the sugar industry in the northern Everglades adjacent to Lake Okeechobee rapidly progressed only after the 1900s. Political and resource management conflicts have arisen because policies which once favored development are now being reversed by policies and regulation efforts to restore and conserve natural ecosystems. Currently, the environmental and ecological impacts of agricultural land use adjacent to natural wtlands of the Everglades are being assessed. The objectives of this paper are: (1) to outline the historical development of south Florida and the sugar industry, (2) to relate this history to political and management policy changes occurring as it pertains to ecosystem restoration and the multiuser competition for water/land resources, and (3) to propose how integrated resource management might be utilized for a sustainable Everglades and south Florida. This paper outlines the historical paradox of urban settlement, land development, and agricultural production, with efforts in the recent decade to acquire, manage, and preserve land and water resources for natural areas conservation. Only though the use of integrated resource management will the defined resource conflicts be mediated. 相似文献
566.
Alicia L. Carriquiry F. Jay Breidt P. G. Lakshminarayan 《Environmental management》1998,22(4):505-515
/ Evaluating the environmental and economic impacts of agricultural policies is not a simple task. A systematic approach to evaluation would include the effect of policy-dependent factors (such as tillage practices, crop rotations, and chemical use) as well as the effect of policy-independent covariates (such as weather, topography, and soil attributes) on response variables (such as amount of soil eroded or chemical leached into the groundwater). For comparison purposes, the effects of these input combinations on the response variable would have to be assessed under competing policy scenarios. Because the number of input combinations is high in most problems, and because policies to be evaluated are often not in use at the time of the study, practitioners have resorted to simulation experiments to generate data. However, generating data from simulation models is often costly and time consuming; thus, the number of input combinations in a study may be limiting even in simulation experiments. In this paper, we discuss the problem of designing computer simulation experiments that require generating data for just a fraction of the possible input combinations. We propose an approach that is based on subsampling the 1992 National Resources Inventory (NRI) points. We illustrate the procedure by assessing soil erosion in a situation where there are "observed" data [reported by the Natural Resources Conservation Service (NRCS)] for comparison. Estimates for soil erosion obtained using the procedure we propose are in good agreement with NRCS reported values.KEY WORDS: Metamodel; National Resources Inventory; Nonpoint source pollution 相似文献
567.
568.
One of the major management problems in protected areas of developing nations is the ever more intensifying land use disputes with local, often native, people. The customary rights oflocal people over natural resources, if curtailed by the establishment of national parks, and their disregard by decision-makers, have given rise to open conflicts, thus jeopardizing conservation goals. These conflicts have tremendous impact on the management of natural resources, not only within the park ecosystem but also in its surroundings. To attain the interdependent goals of conservation and sustainable development, such disputes must be promptly and consensually settled. This paper briefly discusses the paradigm of national park establishment and its impact on local livelihood. It then highlights major sources of conflict which have occurred in national parks in developing countries. Some theoretical approaches to conflict resolution as relevant to national parks are summarized, and several strategies, as employed in particular situations, are discussed. It is concluded that an in-depth understanding of human ecology beyond the boundaries of parks and the conceptualization of strategies to resolve the innate problems are imperative. The integration of several strategies is deemed essential in order to address issues comprehensively and on a larger scale. 相似文献
569.
《Environmental Communication: A Journal of Nature and Culture》2013,7(4):462-468
In his recurrent examination of what makes Americans “American,” documentary filmmaker Ken Burns has particularly focused on the twin themes of democracy and improvisation. The National Parks: America's Best Idea links the national park ideal with America's “democratic spirit.” Through an examination of its visual methods, I argue that the “Ken Burns gaze” is more consistent with the contemplative and magisterial visuality that shaped the origins of the national park movement—a visuality that sees nature as “out there” and a “finished product”—than it is with the improvisational spirit that both democracy and ecology demand in our time. 相似文献
570.
Large amounts of waterborne nutrients are major problems for society since they can cause harmful algal blooms in surface water bodies. Consequently, there are a variety of national and international guidelines, e.g. Swedish National Environmental Quality Objectives and the EU Water Framework Directive, which include targets to be achieved within a certain time frame. This paper uses the example of a large Swedish lake to show that national and international targets must be adapted to the local situations. Despite decreasing nutrient concentrations, cyanobacterial blooms in the lake have increased over recent years. We found that these blooms coincide with depleted nitrate–nitrogen concentrations and increased water temperatures. We propose a simple model with water temperature, nitrate–nitrogen and total phosphorus concentrations as input variables as a basis for formulation of regional eutrophication targets. Political decisions should be preceded by open discussion between policymakers and scientists to differentiate between real knowledge, assumptions or feelings. For optimal results, recommendations for reducing nutrient load should consider all sources, including urban stormwater and wastewater from rural houses, and should be founded on a balanced reduction in emissions of algae-available nutrients. In addition, climate change calls for more effective environmental policy to protect surface water resources. 相似文献