全文获取类型
收费全文 | 461篇 |
免费 | 14篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 22篇 |
废物处理 | 23篇 |
环保管理 | 133篇 |
综合类 | 43篇 |
基础理论 | 112篇 |
污染及防治 | 92篇 |
评价与监测 | 32篇 |
社会与环境 | 12篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 6篇 |
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 9篇 |
2017年 | 11篇 |
2016年 | 12篇 |
2015年 | 8篇 |
2014年 | 13篇 |
2013年 | 31篇 |
2012年 | 17篇 |
2011年 | 24篇 |
2010年 | 18篇 |
2009年 | 16篇 |
2008年 | 30篇 |
2007年 | 29篇 |
2006年 | 22篇 |
2005年 | 16篇 |
2004年 | 17篇 |
2003年 | 22篇 |
2002年 | 17篇 |
2001年 | 19篇 |
2000年 | 13篇 |
1999年 | 8篇 |
1998年 | 8篇 |
1997年 | 8篇 |
1996年 | 7篇 |
1995年 | 10篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1983年 | 5篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 4篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1966年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有477条查询结果,搜索用时 320 毫秒
441.
Joshua J. Lawler§ Denis White Jean C. Sifneos† Lawrence L. Master‡ 《Conservation biology》2003,17(3):875-882
442.
The relationship between adaptation and mitigation in managing climate change risks: a regional response from North Central Victoria,Australia 总被引:1,自引:0,他引:1
Roger N. Jones Paul Dettmann Geoff Park Maureen Rogers Terry White 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):685-712
This two-part paper considers the complementarity between adaptation and mitigation in managing the risks associated with
the enhanced greenhouse effect. Part one reviews the application of risk management methods to climate change assessments.
Formal investigations of the enhanced greenhouse effect have produced three generations of risk assessment. The first led
to the United Nations Intergovernmental Panel on Climate Change (IPCC), First Assessment Report and subsequent drafting of
the United Nations Framework Convention on Climate Change. The second investigated the impacts of unmitigated climate change
in the Second and Third IPCC Assessment Reports. The third generation, currently underway, is investigating how risk management
options can be prioritised and implemented. Mitigation and adaptation have two main areas of complementarity. Firstly, they
each manage different components of future climate-related risk. Mitigation reduces the number and magnitude of potential
climate hazards, reducing the most severe changes first. Adaptation increases the ability to cope with climate hazards by
reducing system sensitivity or by reducing the consequent level of harm. Secondly, they manage risks at different extremes
of the potential range of future climate change. Adaptation works best with changes of lesser magnitude at the lower end of
the potential range. Where there is sufficient adaptive capacity, adaptation improves the ability of a system to cope with
increasingly larger changes over time. By moving from uncontrolled emissions towards stabilisation of greenhouse gases in
the atmosphere, mitigation limits the upper part of the range. Different activities have various blends of adaptive and mitigative
capacity. In some cases, high sensitivity and low adaptive capacity may lead to large residual climate risks; in other cases,
a large adaptive capacity may mean that residual risks are small or non-existent. Mitigative and adaptive capacity do not
share the same scale: adaptive capacity is expressed locally, whereas mitigative capacity is different for each activity and
location but needs to be aggregated at the global scale to properly assess its potential benefits in reducing climate hazards.
This can be seen as a demand for mitigation, which can be exercised at the local scale through exercising mitigative capacity.
Part two of the paper deals with the situation where regional bodies aim to maximise the benefits of managing climate risks
by integrating adaptation and mitigation measures at their various scales of operation. In north central Victoria, Australia,
adaptation and mitigation are being jointly managed by a greenhouse consortium and a catchment management authority. Several
related studies investigating large-scale revegetation are used to show how climate change impacts and sequestration measures
affect soil, salt and carbon fluxes in the landscape. These studies show that trade-offs between these interactions will have
to be carefully managed to maximise their relative benefits. The paper concludes that when managing climate change risks,
there are many instances where adaptation and mitigation can be integrated at the operational level. However, significant
gaps between our understanding of the benefits of adaptation and mitigation between local and global scales remain. Some of
these may be addressed by matching demands for mitigation (for activities and locations where adaptive capacity will be exceeded)
with the ability to supply that demand through localised mitigative capacity by means of globally integrated mechanisms. 相似文献
443.
F. White 《Marine Biology》1970,5(1):29-34
Observations were made of the chromosomes of the burrowing barnacle Trypetesa lampas (Hancock). A method of squash preparation was used, which incorporated staining the material in a solution of 2% orcein in 45% acetic acid. The diploid number of chromosomes of T. lampas was found to be 12 and the haploid number 6, in both males and females. No obvious chromosomal mechanism of sex determination was found. There was, therefore, no cytogenetic confirmation of Kühnert's view (1934) that the sex of the larva is predetermined genetically. During mitosis in the females and embryos of Trypetesa lateralis
Tomlinson and Kochlorine floridana
Wells and Tomlinson, the diploid number of chromosomes was found to be about 14. The numbers of chromosomes in the 3 species of Acrothoracica studied were approximately half those observed in all 12 species of Thoracica and all 5 species of Rhizocephala previously investigated. 相似文献
444.
David R. Anderson Gary C. White Kenneth P. Burnham 《Environmental and Ecological Statistics》1995,2(2):91-115
We present three empirical methods for risk assessment in field studies of free-ranging vertebrates. First, we advocate statistical inference concerning population recruitment or mortality in response to ecological hazards. Second, if inferences about both recruitment and mortality are available, one can use a Leslie- Lefkovitch matrix to estimate the finite rate of population change () as a function of ecological hazards. Third, designed experiments can be conducted on samples of marked animals in natural environments to assess impacts and risks. These methods rely on either sophisticated capture-recapture or radio-tracking models, and on well-developed analysis theory. The use of uniquely marked animals is somewhat analogous to the use of tracers in other areas of risk assessment. We present examples of each approach and discuss some limitations. 相似文献
445.
David E. Kromm Stephen E. White 《Journal of the American Water Resources Association》1990,26(6):999-1012
ABSTRACT: The High Plains has been viewed as an immense garden because of its highly productive agricultural system based on irrigation. But there is concern that the aquifers are being depleted and that the region may be returning to its natural state of a vast shortgrass prairie. Efforts to avoid this scenario and to ensure continued survival of the integrated agribusiness economy focus on conserving water in irrigation. This paper examines the adoption of 39 water-saving practices for ten counties in Kansas, Nebraska, Oklahoma, and Texas. The frequency of adoption was estimated from a survey of 709 irrigators, and the variance was found primarily to be a function of location and secondarily to be influenced by number of wells, type of irrigation system, depth to water, age, and education. Locational differences remained strong even when the influence of secondary factors were controlled. 相似文献
446.
Sea-level rise: Destruction of threatened and endangered species habitat in South Carolina 总被引:1,自引:0,他引:1
Concern for the environment has increased over the past century, and the US Congress has responded to this concern by passing
legislation designed to protect the nation’s ecological biodiversity. This legislation, culminating with the Endangered Species
Act of 1973, has been instrumental in defining methods for identifying and protecting endangered or threatened species and
their habitats. Current legislation, however, assumes that the range of a protected species will stay constant over time.
This assumption may no longer be valid, as the unprecedented increase in the number and concentration of greenhouse gases
in the atmosphere has the potential to cause a global warming of 1.0–4.5°C and a sea-level rise (SLR) of 31–150 cm by the
year 2100. Changes in climate of this magnitude are capable of causing shifts in the population structure and range of most
animal species.
This article examines the effects that SLR may have on the habitats of endangered and threatened species at three scales.
At the regional scale 52 endangered or threatened plant and animal species were found to reside within 3 m of mean sea level
in the coastal stages of the US Southeast. At the state level, the habitats of nine endangered or threatened animals that
may be at risk from future SLR were identified. At the local level, a microscale analysis was conducted in the Cape Romain
National Wildlife Refuge, South Carolina, USA, on the adverse effects that SLR may have on the habitats of the American alligator,
brown pelican, loggerhead sea turtle, and wood stork.
Prepared by the Oak Ridge National Laboratory, Environmental Sciences Division, Oak Ridge, Tennessee 37831, USA; managed by
Martin Marietta Energy Systems. Inc. for the US Department of Energy under contract DE-AC05-84OR21400. 相似文献
447.
448.
449.
450.