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891.
B. M. Kellett R. I. Beilin K. L. Bristow G. Moore F. H. S. Chiew 《The Environmentalist》2007,27(1):109-117
A new form of Ecological Risk Assessment aims to improve environmental decision-making through strong stakeholder engagement,
often in workshop situations. This wider focus increases interaction between workshop practitioners and stakeholders for reflecting
on, and learning from, each others perceptions. In this article, we analyse and discuss a one day workshop that was concerned
with trialling this method of deriving an Ecological Risk Assessment. We found that stakeholders had issues with some elements
of the workshop process. The decision problem was formulated prior to the workshop and without consultation among all the
stakeholders. Consequently, the original decision problem was rejected for a mutually derived broader focus and this resulted
in a loss of clarity and purpose. Stakeholders did not wholly concur with the prioritising of ecological values over social
and economic values and some stakeholders objected to defining assessment endpoints, because it implies a reductionist approach
that doesn’t capture significance and understanding of systems. Ecological Risk Assessment workshops are complex and require
significant practitioner and stakeholder development to provide useful and mutually derived outcomes. 相似文献
892.
/ Arthropod communities from several habitats on and adjacent to the El Segundo dunes (Los Angeles County, CA) were sampled using pitfall and yellow pan traps to evaluate their possible use as indicators of restoration success. Communities were ordinated and clustered using correspondence analysis, detrended correspondence analysis, two-way indicator species analysis, and Ward's method of agglomerative clustering. The results showed high repeatability among replicates within any sampling arena that permits discrimination of (1) degraded and relatively undisturbed habitat, (2) different dune habitat types, and (3) annual change. Canonical correspondence analysis showed a significant effect of disturbance history on community composition that explained 5-20% of the variation. Replicates of pitfall and yellow pan traps on single sites clustered together reliably when species abundance was considered, whereas clusters using only species incidence did not group replicates as consistently. The broad taxonomic approach seems appropriate for habitat evaluation and monitoring of restoration projects as an alternative to assessments geared to single species or even single families. 相似文献
893.
/ Many of the aquatic and terrestrial ecosystems of the Pacific Northwest United States have been simplified and degraded in part through past land-management activities. Recent listings of fishes under the Endangered Species Act and major new initiatives for the restoration of forest health have precipitated contentious debate among managers and conservation interests in the region. Because aggressive management activities proposed for forest restoration may directly affect watershed processes and functions, the goals of aquatic and terrestrial conservation and restoration are generally viewed as in conflict. The inextricable links in ecological processes and functions, however, suggest the two perspectives should really represent elements of the same problem; that of conserving and restoring more functional landscapes. We used recent information on the status and distribution of forest and fish communities to classify river subbasins across the region and explore the potential conflict and opportunity for a more integrated view of management. Our classification indicated that there are often common trends in terrestrial and aquatic communities that highlight areas of potential convergence in management goals. Regions where patterns diverge may emphasize the need for particular care and investment in detailed risk analyses. Our spatially explicit classification of subbasin conditions provides a mechanism for progress in three areas that we think is necessary for a more integrated approach to management: (1) communication among disciplines; (2) effective prioritization of limited conservation and restoration resources; and (3) a framework for experimentation and demonstration of commitment and untested restoration techniques. 相似文献
894.
Dr. R. Harold Holbrook Jr Ann M. Krovoza Susan Schelley James E. Ferguson II 《黑龙江环境通报》1987,7(9):653-655
Anencephaly in twin B was accompanied by elevated amniotic fluid alpha-fetoprotein (AFP) and a positive acetylcholinesterase (AChE) band on gel electrophoresis in both twin sacs, although twin A was normal. AChE results did not help distinguish the false positive AFP in this set of twins, implying that AChE may diffuse transamniotically as has been previously postulated for AFP. In light of the low concordance rate for neural tube defects in twins, patient counselling in this situation must include the information that AFP and AChE may be falsely elevated in normal twin when the other twin has a neural tube defect. 相似文献
895.
Direct preparations and long-term cultures from a chorion villus biopsy, taken because of a known maternal additional marker chromosome, showed a 48,XX,+mar,+mar karyotype in all cells examined. The same karyotype was revealed in a subsequent amniotic fluid sample and in cord blood at delivery. Detailed examination of the child at delivery and at 1 year of age showed no evidence of phenotypic abnormality or developmental problems. 相似文献
896.
Data collected from 172 sites in 20 major river basins between 1993 and 1995 as part of the US Geological Survey's National
Water-Quality Assessment Program were analyzed to assess relations among basinwide land use (agriculture, forest, urban, range),
water physicochemistry, riparian condition, and fish community structure. A multimetric approach was used to develop regionally
referenced indices of fish community and riparian condition. Across large geographic areas, decreased riparian condition was
associated with water-quality constituents indicative of nonpoint source inputs—total nitrogen and suspended sediment and
basinwide urban land use. Decreased fish community condition was associated with increases in total dissolved solids and rangeland
use and decreases in riparian condition and agricultural land use. Fish community condition was relatively high even in areas
where agricultural land use was relatively high (>50% of the basin). Although agricultural land use can have deleterious effects
on fish communities, the results of this study suggest that other factors also may be important, including practices that
regulate the delivery of nutrients, suspended sediments, and total dissolved solids into streams. Across large geographic
scales, measures of water physicochemistry may be better indicators of fish community condition than basinwide land use. Whereas
numerous studies have indicated that riparian restorations are successful in specific cases, this analysis suggests the universal
importance of riparian zones to the maintenance and restoration of diverse fish communities in streams. 相似文献
897.
Preston BL 《Environmental management》2002,29(3):311-323
Understanding toxicant effects at higher levels of biological organization continues to be a challenge in ecotoxicology and
ecological risk assessment. This is due in part to a tradition in ecotoxicology of considering the direct effects of toxicants
on a limited number of model test species. However, the indirect effects of toxicity may be a significant factor influencing
the manner in which ecosystem structure and function respond to anthropogenic stressors. Subsequently, failure to incorporate
indirect effects into risk assessment paradigms may be a significant source of uncertainty in risk estimates. The current
paper addresses the importance of indirect effects in an ecotoxicological context. Laboratory, mesocosm, and whole ecosystem
research into indirect effects is reviewed. The implications of indirect effects for ecological risk assessment and potential
areas of profitable future research are also discussed. 相似文献
898.
Restoration,stewardship, environmental health,and policy: understanding stakeholders' perceptions 总被引:1,自引:0,他引:1
Burger J 《Environmental management》2002,30(5):0631-0640
In recent years there has been considerable interest in the health of humans and the environment, restoration of contaminated
or otherwise degraded lands, and in long-term stewardship of public lands. Unfortunately, it is unclear whether governmental
agencies and the public hold similar views about the meanings of these concepts, making policy decisions about restoration
and stewardship difficult. In this paper, I explore how the public conceptualizes restoration and stewardship by examining
the relative rating of several attributes of restoration, stewardship, environmental health, ecological health, environmental
restoration, and ecological restoration. People were interviewed in Santa Fe, New Mexico, USA, near the Department of Energy's
Los Alamos National Laboratory. The ratings of attributes of environmental health and ecological health reported in this paper
can be used to understand how the public understands these concepts. The attributes rated most highly by the subjects were
more similar to definitions in the scientific literature for these terms than they were to those used by the Department of
Energy. For environmental health, the highest rating related to human sanitation, while for ecological health the highest
rating was for maintaining functioning ecosystems. Reduction of exposure to hazardous substances was rated the second highest
for both environmental and ecological health. The wise use of natural resources, preservation of natural resources, and hazardous
waste site cleanup were rated the highest attributes of stewardship. These data suggest that both expert and nonexpert perceptions
about restoration and stewardship should be incorporated into environmental management decisions. 相似文献
899.
900.
国家级生态示范区阆中市森林生态效益评估 总被引:4,自引:0,他引:4
森林生态效益是一种间接的经济利益。本文通过水土保持,水源涵养,减免旱涝灾害,环境保护等各方面的效益评估。将阆中市森林生态效益用货币体现,科学直观地反映了阆中森林生态工程的经济价值。 相似文献