全文获取类型
收费全文 | 2671篇 |
免费 | 126篇 |
国内免费 | 107篇 |
专业分类
安全科学 | 776篇 |
废物处理 | 16篇 |
环保管理 | 526篇 |
综合类 | 694篇 |
基础理论 | 246篇 |
环境理论 | 2篇 |
污染及防治 | 118篇 |
评价与监测 | 140篇 |
社会与环境 | 133篇 |
灾害及防治 | 253篇 |
出版年
2024年 | 4篇 |
2023年 | 31篇 |
2022年 | 34篇 |
2021年 | 70篇 |
2020年 | 81篇 |
2019年 | 54篇 |
2018年 | 29篇 |
2017年 | 82篇 |
2016年 | 96篇 |
2015年 | 98篇 |
2014年 | 84篇 |
2013年 | 146篇 |
2012年 | 140篇 |
2011年 | 224篇 |
2010年 | 120篇 |
2009年 | 168篇 |
2008年 | 143篇 |
2007年 | 163篇 |
2006年 | 137篇 |
2005年 | 144篇 |
2004年 | 120篇 |
2003年 | 135篇 |
2002年 | 95篇 |
2001年 | 68篇 |
2000年 | 69篇 |
1999年 | 60篇 |
1998年 | 34篇 |
1997年 | 44篇 |
1996年 | 28篇 |
1995年 | 31篇 |
1994年 | 24篇 |
1993年 | 36篇 |
1992年 | 25篇 |
1991年 | 17篇 |
1990年 | 9篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 8篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1981年 | 9篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有2904条查询结果,搜索用时 593 毫秒
651.
Abstract: In a preliminary analysis of listing decisions under Canada's Species at Risk Act (SARA), Mooers et al. (2007) demonstrated an apparent bias against marine and northern species. As a follow‐up, we expanded the set of potential explanatory variables, including information on jurisdictional and administrative elements of the listing process, and considered an additional 16 species recommended for listing by SARA's scientific advisory committee as of 15 August 2006. Logistic model selection based on Akaike differences suggested that species were less likely to be listed if they were harvested or had commercial or subsistence harvesting as an explicitly identified threat; had Department of Fisheries and Oceans (DFO) as a responsible authority (RA); were located in Canada's north generally, and especially in Nunavut; or were found mostly or entirely within Canada. Subsequent model validation with an independent set of 50 species for which a listing decision was handed down in December 2007 showed an overall misclassification rate of <0.10, indicating reasonable predictive power. In light of these results, we recommend that RAs under SARA adopt a two‐track listing approach to address problems of delays arising from extended consultations and the inconsistent use by the RAs of socioeconomic analysis; consider revising SARA so that socioeconomic analysis occurs during decisions about protecting species and their habitats rather than at the listing stage; and maintain an integrated database with information on species’ biology, threats, and agency actions to enable future evaluation of SARA's impact. 相似文献
652.
The need to safely field test genetically modified organisms is a critical step in the sequence of research leading to the commercialization of biotechnology in agriculture. To address this need the United States Department of Agriculture has established the National Biological Impact Assessment Program (NBIAP) to facilitate the safe field testing of genetically modified organisms. NBIAP fosters safe field testing of genetically modified organisms through a computerized network for information exchange, facilitation of biological monitoring techniques and by providing support for research in biosafety to develop new field testing methods and better predictive models. 相似文献
653.
Paul Scott Paul Brown Julia Verne Jody James Alistair Gordon Joyshri Sarangi Jonathan A. C. Sterne 《Environmental geochemistry and health》2009,31(2):297-308
This ecological study aimed, through the analysis of 1,146 wards in the South West of England (1998–2002), firstly, to examine
whether chemical incidents and public casualties are more likely near complex industry (emissions to land, air or water: Integrated
Pollution Control industry, IPC) or industry with emissions to air only (Local Air Pollution Control industry, LAPC). Secondly,
the study examined whether industry, incidents and casualties are found close to deprivation. Social inequalities were examined
across quintiles of wards. Fifty-two wards (4.5%) contained an IPC industry and 712 (62.1%) an LAPC. Incidents occurred in
132 wards (11.5%), with casualties in 59 (5.1%). Chemical incidents occurred more frequently in wards with LAPC (152, IPC
20); the same was true of casualties (211, 12). With each additional LAPC site in a ward, the risk of an incident rose by
22% (95% confidence interval [CI] 8–38%), suggesting a dose–response relationship. No clear social inequalities were found.
In the South West of England, the public are more likely to be affected by an incident occurring at a simple LAPC site rather
than a complex IPC site. This has implications for emergency planning which, at present, focusses most attention on the larger,
more complex IPC sites. 相似文献
654.
L. Cordonnery 《Journal of environmental management》1999,56(4):285
With the entry into force of the Protocol on Environmental Protection to the Antarctic Treaty (the Protocol) in January 1998, key operational aspects of the newly established Committee for Environmental Protection (CEP), such as its advisory capacity to Antarctic Treaty Consultative Meetings (ATCMs) need to be urgently addressed. This paper advocates the use of a geographic information system (GIS) environmental database to reinforce the advisory capacity of the CEP. The demonstrated links between the provisions of the Protocol and GIS capabilities illustrate the potential this has to assist the CEP in delivering informed advice to ATCMs. The range of GIS applications that could be utilized by the CEP in fulfilling its functions are examined by reference to precedents in Europe (CORINE) and Australia (ARIS). 相似文献
655.
Models to Assess the Risk of Snow and Wind Damage in Pine, Spruce, and Birch Forests in Sweden 总被引:2,自引:0,他引:2
3 are damaged annually by snow and wind, roughly corresponding to a value of US$150 million, and in Europe, the damage amounts
to hundreds of millions of US dollars each year. To help to reduce these losses, tools for risk assessment within forest management
have been developed. Predictions were developed of the risk of damage from snow and wind to Scots pine (Pinus sylvestris L.), Norway spruce [Picea abies (L.) Karst.] and Birch (Betula spp. L.) plots using tree, stand, and site characteristics. The data were obtained from 6756 permanent sample plots within
the Swedish National Forest Inventory, which were inventoried twice at five-year intervals between 1983 and 1992. Input data
for model development used measurements from the first inventory of tree characteristics for the largest sample tree, stand,
and site data, and records of snow and wind damage from the second inventory. Models were developed for three different regions
for pine- and spruce-dominated sites, while models for the whole country were developed for birch sites. In general the estimated
proportion of damaged plots was highly overestimated (31.7%–56.2%), compared with the observed proportion of 3.4%–11.9%. The
models for Norway spruce comprising tree, stand, and site data show the best predictability of damaged plots, with 60.6%–67.6%
of plots correctly classified. It is concluded that the models developed can be used to detect sites with a high probability
of damage from snow and wind, and thus be used as tools to reduce future damage and costs in practical forestry. 相似文献
656.
657.
658.
659.
Gabriele Fava Romeo Fratesi Maria Letizia Ruello Daniela Sani 《Chemistry and Ecology》2013,29(3-4):223-232
The present work relates to galvanized structures with several years of time life subjected to atmospheric corrosion, like galvanized high tension steel pylons. The mass and fate of zinc released is evaluated both via empirical and experimental procedures. The corrosion rate determination requested atmospheric condition characterization, especially for SO 2 concentration and experimental activities focused on soil sampling around pylons. The soil zinc content, total and exchangeable, is determinates by different analytical procedures. The zinc diffusion in environment and the zinc extension under the top soil is evaluated using 1-dimensional mathematical model for miscible species in porous soil. 相似文献
660.
ASTRID J. SCHOLZ CHARLES STEINBACK SARAH A. KRUSE MIKE MERTENS HOWARD SILVERMAN 《Conservation biology》2011,25(3):485-492
Abstract: Social, economic, and ecological criteria contribute to the successful design, implementation, and management of marine protected areas (MPAs). In the context of California's Marine Life Protection Act Initiative, we developed a set of methods for collecting, compiling, and analyzing data about the spatial extent and relative economic importance of commercial and recreational fishing. We interviewed 174 commercial fishers who represented the major fisheries in the initiative's north‐central coast region, which extends from Point Arena south to Pigeon Point. These fishers provided data that we used to map the extent of each of the fishing grounds, to weight the relative importance of areas within the grounds, to characterize the operating costs of each fishery, and to analyze the potential economic losses associated with proposed marine protected areas. A regional stakeholder group used the maps and impact analyses in conjunction with other data sets to iteratively identify economic and ecological trade‐offs in designations of different areas as MPAs at regional, port, and fishery extents. Their final proposed MPA network designated 20% of state waters as MPAs. Potential net economic loss ranged from 1.7% to 14.2% in the first round of network design and totaled 6.3% in the final round of design. This process is a case study in the application of spatial analysis to validate and integrate local stakeholder knowledge in marine planning. 相似文献