全文获取类型
收费全文 | 159篇 |
免费 | 1篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 19篇 |
废物处理 | 1篇 |
环保管理 | 55篇 |
综合类 | 50篇 |
基础理论 | 15篇 |
污染及防治 | 8篇 |
评价与监测 | 4篇 |
社会与环境 | 4篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 3篇 |
2020年 | 5篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 6篇 |
2016年 | 5篇 |
2015年 | 7篇 |
2014年 | 9篇 |
2013年 | 3篇 |
2012年 | 4篇 |
2011年 | 14篇 |
2010年 | 2篇 |
2009年 | 11篇 |
2008年 | 9篇 |
2007年 | 24篇 |
2006年 | 2篇 |
2005年 | 9篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1985年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有164条查询结果,搜索用时 179 毫秒
61.
NJAL ROLLINSON DAVE M. KEITH AIMEE LEE S. HOUDE PAUL V. DEBES MEGHAN C. MCBRIDE JEFFREY A. HUTCHINGS 《Conservation biology》2014,28(2):529-540
Captive‐breeding programs can be implemented to preserve the genetic diversity of endangered populations such that the controlled release of captive‐bred individuals into the wild may promote recovery. A common difficulty, however, is that programs are founded with limited wild broodstock, and inbreeding can become increasingly difficult to avoid with successive generations in captivity. Program managers must choose between maintaining the genetic purity of populations, at the risk of inbreeding depression, or interbreeding populations, at the risk of outbreeding depression. We evaluate these relative risks in a captive‐breeding program for 3 endangered populations of Atlantic salmon (Salmo salar). In each of 2 years, we released juvenile F1 and F2 interpopulation hybrids, backcrosses, as well as inbred and noninbred within‐population crosstypes into 9 wild streams. Juvenile size and survival was quantified in each year. Few crosstype effects were observed, but interestingly, the relative fitness consequences of inbreeding and outbreeding varied from year to year. Temporal variation in environmental quality might have driven some of these annual differences, by exacerbating the importance of maternal effects on juvenile fitness in a year of low environmental quality and by affecting the severity of inbreeding depression differently in different years. Nonetheless, inbreeding was more consistently associated with a negative effect on fitness, whereas the consequences of outbreeding were less predictable. Considering the challenges associated with a sound risk assessment in the wild and given that the effect of inbreeding on fitness is relatively predictable, we suggest that risk can be weighted more strongly in terms of the probable outcome of outbreeding. Factors such as genetic similarities between populations and the number of generations in isolation can sometimes be used to assess outbreeding risk, in lieu of experimentation. Evaluación del Riesgo de Depresión por Endogamia y Exogamia en un Programa de Reproducción en Cautiverio 相似文献
62.
63.
Integrating mitigation and adaptation into climate and development policy: three research questions 总被引:3,自引:0,他引:3
The potential for developing synergies between climate change mitigation and adaptation has become a recent focus of both climate research and policy. Presumably the interest in synergies springs from the appeal of creating win–win situations by implementing a single climate policy option. However, institutional complexity, insufficient opportunities and uncertainty surrounding their efficiency and effectiveness present major challenges to the widespread development of synergies. There are also increasing calls for research to define the optimal mix of mitigation and adaptation. These calls are based on the misguided assumption that there is one single optimal mix of adaptation and mitigation options for all possible scenarios of climate and socio-economic change, notwithstanding uncertainty and irrespective of the diversity of values and preferences in society. In the face of current uncertainty, research is needed to provide guidance on how to develop a socially and economically justifiable mix of mitigation, adaptation and development policy, as well as on which elements would be part of such a mix. Moreover, research is needed to establish the conditions under which the process of mainstreaming can be most effective. Rather than actually developing and implementing specific mitigation and adaptation options, the objective of climate policy should be to facilitate such development and implementation as part of sectoral policies. Finally, analysis needs to focus on the optimal use and expected effectiveness of financial instruments, taking into account the mutual effects between these instruments on the one hand, and national and international sectoral investments and official development assistance on the other. 相似文献
64.
Michael J. Scott James A. Dirks Katherine A. Cort 《Mitigation and Adaptation Strategies for Global Change》2008,13(4):307-339
US residential and commercial buildings were responsible for about 41 exajoules (EJ) of primary energy use per year in 2002,
accounting for approximately 9% of the world fossil-fuel related anthropogenic carbon (C) emissions of 6.7 Gt that contribute
to climate change. US Government-sponsored building energy efficiency research and implementation programs are focused on
reducing energy consumption in US residential and commercial buildings and reducing these carbon (C) emissions. Although not
specifically intended for adaptation to a warmer climate and less effective than under today’s cooler climate, these programs
also could help reduce energy demand in a future warmer world. Warming scenarios projected by the United Nations Intergovernmental
Panel on Climate Change (IPCC) in 2001 imply net overall decreases in both site energy and primary energy consumption in US
residential and commercial buildings, largely because of the reduced need for heating. However, there would be as much as
a 25% increase in building space cooling demand and a significant part of the increase could be offset by energy-efficiency
improvements in buildings. Overall, in the US, buildings-related energy efficiency programs would reduce site energy consumption
in buildings in the US by more than 2 EJ in 2020 and primary energy by more than 3.5 EJ, more than enough to offset the projected
growth in cooling energy consumption due to climate change and growth in the US building stock. The savings would have an
estimated annual net value at 2005 energy prices of between $45.0 and $47.3 billion to consumers.
相似文献
Michael J. ScottEmail: |
65.
A novel mitigation system against hydrogen-air deflagrations in nuclear power plant buildings is proposed and developed through a series of field experiments using explosion vessels of different volume sizes. The mitigation system is installed on the outer surface of the vessels, and it comprises flame arrester and explosion air bag. The flame arrester is made by stacking 10–20 sheets of fine-mesh wire screens, and the air bag is connected for holding explosion gas. The successful mitigation mechanism is the sequence of pressure-rise reduction by the air bag expansion, flame quenching by the flame arrester, and the slow burning of the gas mixture sucked from the air bag back into the vessel due to the negative pressure caused by the rapid condensation of water vapor inside the vessel. Necessary conditions for the successful mitigation system are discussed, and the practical unit size of flame arrester sheet is recommended. 相似文献
66.
Environmental impact assessment (EIA) is identified as an important instrument for facilitating environmental protection and sustainable development. However, since its emergence there has been a growing interest in examining its translation from theory into practice. This paper reviews the translation of mitigation measures proposed in environmental impact statements (EISs) into planning conditions at two platinum mining and processing projects along the Great Dyke of Zimbabwe. By comparing mitigation measures proposed in EISs and those included in environmental management plans (EMPs), examining views of environmental managers and local residents, as well as field observations the mitigation implementation status is verified and evaluated. Results show that 52% of mitigation measures proposed in EISs and mostly procedural are translated into planning conditions. Residents near the platinum processing plant were not satisfied with the mitigation of sulphur dioxide, dust and noise impacts on their health. The need to incorporate and enforce substantive mitigation measures in EISs and planning conditions is recommended for the future. 相似文献
67.
Bali Action Plan provisions acknowledge the fact that developing countries are already making efforts to reduce emis- sions and move towards a low carbon pathway. The Copenhagen Accord mentions Nationa... 相似文献
68.
Collective actions of stakeholders are required for fulfilling the climate commitments of the Kyoto protocol. The insurance sector's global influence and societal impact is fairly well documented. The sector influences societies based on its interaction with stakeholders, on its products, business and political stance. As such, it is a critical actor in facilitating key climate change actions of mitigation and adaptation, and has already been recognized as a leading sector in terms of climate adaptation. The aim of this paper is to explore the role of non-life insurers in fulfilling the climate commitments of the Kyoto Protocol. This paper is based on a case study on Nordic non-life insurance companies. The study documents that Nordic insurers are responding to climate-related threats and opportunities in a strategic manner by reducing their own impacts, through their core activities, and by influencing others to act. Although Nordic insurers do not classify their actions into mitigation and adaptation, but classify them according to their core activities, they demonstrate through actions their role as potential allies for nations in fulfilling the Kyoto protocol climate commitments. The study also reveals that the commercial reality of the industry is not the same as the expected contribution to climate commitments, for instance as specified in international conventions and treaties and in the Intergovernmental Panel on Climate Change (IPCC) and industry reports. 相似文献
69.
Abstract: A price on carbon is expected to generate demand for carbon offset schemes. This demand could drive investment in tree‐based monocultures that provide higher carbon yields than diverse plantings of native tree and shrub species, which sequester less carbon but provide greater variation in vegetation structure and composition. Economic instruments such as species conservation banking, the creation and trading of credits that represent biological‐diversity values on private land, could close the financial gap between monocultures and more diverse plantings by providing payments to individuals who plant diverse species in locations that contribute to conservation and restoration goals. We studied a highly modified agricultural system in southern Australia that is typical of many temperate agriculture zones globally (i.e., has a high proportion of endangered species, high levels of habitat fragmentation, and presence of non‐native species). We quantified the economic returns from agriculture and from carbon plantings (monoculture and mixed tree and shrubs) under six carbon‐price scenarios. We also identified high‐priority locations for restoration of cleared landscapes with mixed tree and shrub carbon plantings. Depending on the price of carbon, direct annual payments to landowners of AU$7/ha/year to $125/ha/year (US$6–120/ha/year) may be sufficient to augment economic returns from a carbon market and encourage tree plantings that contribute more to the restoration of natural systems and endangered species habitats than monocultures. Thus, areas of high priority for conservation and restoration may be restored relatively cheaply in the presence of a carbon market. Overall, however, less carbon is sequestered by mixed native tree and shrub plantings. 相似文献
70.
Development projects that impact wetlands commonly require compensatory mitigation, usually through creation or restoration
of wetlands on or off the project site. Over the last decade, federal support has increased for third-party off-site mitigation
methods. At the same time, regulators have lowered the minimum impact size that triggers the requirement for compensatory
mitigation. Few studies have examined the aggregate impact of individual wetland mitigation projects. No previous study has
compared the choice of mitigation method by regulatory agency or development size. We analyze 1058 locally and federally permitted
wetland mitigation transactions in the Chicago region between 1993 and 2004. We show that decreasing mitigation thresholds
have had striking effects on the methods and spatial distribution of wetland mitigation. In particular, the observed increase
in mitigation bank use is driven largely by the needs of the smallest impacts. Conversely, throughout the time period studied,
large developments have rarely used mitigation banking, and have been relatively unaffected by changing regulatory focus and
banking industry growth. We surmise that small developments lack the scale economies necessary for feasible permittee responsible
mitigation. Finally, we compare the rates at which compensation required by both county and federal regulators is performed
across major watershed boundaries. We show that local regulations prohibiting cross-county mitigation lead to higher levels
of cross- watershed mitigation than federal regulations without cross-county prohibitions. Our data suggest that local control
over wetland mitigation may prioritize administrative boundaries over hydrologic function in the matter of selecting compensation
sites. 相似文献