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341.
The flagship of the Environmental Protection Agency's regulatory reinvention initiative, Project XL has been touted as a regulatory
blueprint for a site-specific, performance-based pollution-control system, but widespread complaints about the costs of the
program beg the question of whether the costs of tailoring regulations to individual facilities are manageable. To address
this question, this paper presents original survey data on a sample of 11 XL projects. We find that the fixed costs of putting
in place XL agreements are substantial, averaging over $450,000 per firm. While stakeholder negotiations are widely cited
as the principal source for these costs, we find that they actually arise mainly from interaction between participating facilities
and the EPA. Moreover, EPA management problems are perceived by our survey respondents as having inflated project development
costs. Finally, we find that the key factors that explains differences in costs across XL projects are the scope and complexity
of the project proposal. These findings suggest that Project XL favors large firms that can afford to pay significant project
development costs, that EPA management problems must be resolved to reduce costs, and that there may be a significant economic
bias against complex and innovative proposals—precisely the type of proposals that Project XL was designed to foster in order
to improve the efficiency of the regulatory system. 相似文献
342.
Policy makers often must rely on the cumulative impact of independent actions taken by local landowners to achieve environmental
goals. The connection between policy, regulation, and local action, however, is often not well understood and, thus, the impact
of proposed policies may be difficult to predict. In this study we evaluate the effectiveness of alternative policy scenarios
for agricultural set aside programs (e.g., the conservation reserve program administered by the United States Department of
Agriculture) in reducing nonpoint pollution. Two alternative policy scenarios are developed and analyzed; one based on the
erodibility index (detachment), the other sediment yield (transport). An estimate of the cumulative impact of associated land
use change on nonpoint pollution is made using the AGNPS distributed parameter watershed model. This work is completed within
the Cypress Creek watershed in southern Illinois. An analysis of the resulting data suggests that the most efficacious regulatory
strategy for achieving nonpoint water pollution goals depends, in part, on place-specific land use patterns. This conclusion
provides a solid argument for place-based regulatory strategies. 相似文献
343.
This paper sheds light on changing farmers' land management practices in two mountain watersheds, with and without external
assistance, in the western hills of Nepal. Information used in the analysis were obtained through a survey of 300 households,
group discussion, key informant interviews, and field observation conducted during April–September 1999. Confronted with ever-decreasing
landholding size due to a steadily growing population and scarcity of nonfarming employment opportunities, farmers in both
watersheds have increasingly adopted assorted types of structural and biological measures to control soil erosion, landslides,
gully expansion, and soil nutrient loss to maintain or even enhance land productivity. Adoption of gully control measures,
construction of the retention walls, alley cropping, use of vegetative measures for landslide control, mulching, and use of
green manure and chemical fertilizers are found significantly high in the project area due to the provision of technical and
financial support, whereas composting is found significantly high in the nonproject area. Different from the traditionally
held beliefs, population pressure on a finite land resource has brought positive change in land management. However, the experience
from both watersheds indicates that there is limit to the extent that resource poor farmers can respond to land degradation
without any external assistance. Required is the arrangement for appropriate polices and support services and facilities enabling
farmers to adopt locationally suitable and economically attractive land management technologies. 相似文献
344.
We use spatial data representing transportation networks, elevation, stand height, and recreation use to construct and compare
models of recreation use patterns and visibility in a forest. The recreation use pattern model depicts use frequencies along
travel corridors. The visibility model quantifies visibility for all forest areas. We find that the models provide different
but complementary types of information. Forest managers who are involved in scheduling harvest operations and want to address
the visual concerns of forest visitors may benefit most from the visibility model. Managers who wish to know more about travel
patterns or to reroute forest visitors affected by operations may benefit from the use pattern model. A combination of the
two models has the highest potential for providing planning assistance in multiple-use forests. Both models may be able to
enhance visual resource management (VRM) systems already in use by providing spatially explicit recreation use and visibility
data. 相似文献
345.
Conservation strategies for effective land management of protected areas using an erosion prediction information system (EPIS) 总被引:1,自引:0,他引:1
This research demonstrates the predictive modeling capabilities of a geographic information system (GIS)-based soil erosion potential model to assess the effects of implementing land use change within a tropical watershed. The Revised Universal Soil Loss Equation (RUSLE) was integrated with a GIS to produce an Erosion Prediction Information System (EPIS) and modified to reflect conditions found in the mountainous tropics. Research was conducted in the Zenzontia subcatchment of the Río Ayuquíla, located within the Sierra de Manantlán Biosphere Reserve (SMBR), México. Expanding agricultural activities within this area will accentuate the already high rate of soil erosion and resultant sediment loading occurring in the Río Ayuquíla. Two land-use change scenarios are modeled with the EPIS: (1) implementation of soil conservation practices in erosion prone locations; and (2) selection of sites for agricultural expansion which minimize potential soil loss. Confronted with limited financial resources and the necessity for expedient action, managers of the SMBR can draw upon the predictive capacity of the EPIS to facilitate rapid and informed land-use planning decisions. 相似文献
346.
Bentrup G 《Environmental management》2001,27(5):739-748
Collaborative planning processes have become increasingly popular for addressing environmental planning issues, resulting
in a number of conceptual models for collaboration. A model proposed by Selin and Chavez suggests that collaboration emerges
from a series of antecedents and then proceeds sequentially through problem-setting, direction-setting, implementation, and
monitoring and evaluation phases. This paper summarizes an empirical study to evaluate if the Selin and Chavez model encompasses
the range of factors important for the establishment and operation of collaboration in watershed planning from the perspective
of the planning coordinator. Analysis of three case studies of watershed based planning efforts in the Intermountain West
suggests the model realistically describes some of the fundamental collaborative elements in watershed planning. Particularly
important factors include the involvement of stakeholders in data collection and analysis and the establishment of measurable
objectives. Informal face-to-face dialog and watershed field tours were considered critical for identifying issues and establishing
trust among stakeholders. Group organizational structure also seems to play a key role in facilitating collaboration. From
this analysis, suggestions for refining the model are proposed. 相似文献
347.
Opio C 《Environmental management》2001,27(1):59-74
Many small holder farmers in developing countries face problems of declining soil fertility and crop yields and insufficient
money to buy expensive inorganic fertilizers. The Sesbania fallow system, an agroforestry technology, seems to hold a key to these problems. Based on field studies in eastern Zambia,
this paper reports that fallow system has the potential to improve and sustain soil productivity in the small holder farms.
However, the paper also reports that the ability for subsistence farmers to adopt the Sesbania fallow system is affected by gender differences in resource allocation to productive resources and institutional, cultural,
and social structural settings in which farmers exist and make decisions. 相似文献
348.
Sorace A 《Environmental management》2001,28(4):547-560
Urban-agricultural parks could have some advantages to wildlife because of less intensive agricultural procedures, absence
of hunting pressure, and reduced human disturbance. In this study, the breeding and wintering bird communities and the small
mammal community in an urban-agricultural park of Rome were compared to those of a close urban park and a close agricultural
area just outside the city. The aim was to assess the best destination and management of wildlife in natural areas at the
urban–rural interface. Richness and diversity of bird communities were higher in the urban-agricultural park. Due to habitat
features and probably human disturbances, but not to urbanization, predation, and competition factors, the urban park drastically
reduces the abundance of decreasing open-land bird species. Abundance of these species was not significantly different in
the urban-agricultural park and in the agricultural area. In the urban-agricultural and urban park, bird and mammal pest species
were more abundant than they were in the agricultural area. Regarding decreasing abundance of small mammal species, no significant
difference among the study areas was observed. Urban-agricultural park is a better choice than urban park for wildlife. Thus,
a higher number of preserved urban natural areas should be devoted to urban-agricultural parks. However, to increase the abundance
of open-land species and in general wildlife, a less intensive management of cultivated and pasture patches is necessary. 相似文献
349.
Traditional Land-Use Systems and Patterns of Forest Fragmentation in the Highlands of Chiapas, Mexico 总被引:1,自引:0,他引:1
Ochoa-Gaona S 《Environmental management》2001,27(4):571-586
The influence of slash-and-burn agriculture and tree extraction on the spatial and temporal pattern of forest fragmentation
in two municipalities in the highlands of Chiapas, Mexico was analyzed. The data series were derived from two subsets of satellite
images taken in 1974 and 1996. The analysis was based on area, edge, shape, core area, and neighbor indices. During the 22
years, the dense forest decreased by 8.9%/yr in Huistán and by 8.6%/yr in Chanal, while open/disturbed forest, secondary vegetation,
and developed area increased in both municipalities. The total number of fragments increased by 1.4%/yr and 2.3%/yr in Huistán
and Chanal, respectively. Dense forest showed the highest increase in the number of fragments (6%/yr in Huistán and 12%/yr
in Chanal), while edge length, core area, and number of dense forest core areas decreased. The larger fragments of dense forest
present in 1974 were divided into smaller fragments in 1996; at the same time, they experienced a process of degradation toward
open/disturbed forest and secondary vegetation. Two different fragmentation patterns could be distinguished based on agricultural
or forestry activities. Forest fragmentation did not occur as a continuous process; the pattern and degree of fragmentation
were functions of land tenure, environmental conditions, and productive activities. The prevalence of rather poor soil conditions,
small-holdings, growing human population densities, increasing poverty, and the absence of alternative economic options will
maintain a high rate of deforestation and forest fragmentation in the studied region. 相似文献
350.
Populations of threatened species, especially predators at the top of the food chain, may be affected by anthropic pressures. The endangered western population of European mink Mustela lutreola has shown a large decline over 50% of its natural range. M. lutreola disappeared from northwestern France between 1984 and 1997, and the decline was associated with an increase in mustelid trapping, changes in watercourse quality, and habitat modifications due to agricultural practices. The pattern of decline showed a fragmentation restricting the minks into very small areas. Trapping was the first known cause of mortality. Although feral American mink Mustela vison may compete with autochthonous carnivores, M. lutreola had disappeared from streams before the introduction of the American species, suggesting that competitive interactions were not responsible. Furthermore, American mink has never been found or has remained rare in 62.4% of the area from which M. lutreola has disappeared. During the past 25 years, permanent grassland surfaces were reduced by 40%, whereas fodder culture increased by 470%, causing considerable habitat changes. Furthermore, 55.7% of water courses were classified as being of bad quality or polluted. Therefore, our data suggests that a conjunction of intensive trapping, alterations in water quality and habitat modification was critical for the European mink's decline. Although there are difficulties in ascribing specific cause to distribution changes in a top predator, this decline can be regarded as an indication for anthropic pressures on natural habitats. 相似文献