全文获取类型
收费全文 | 979篇 |
免费 | 78篇 |
国内免费 | 63篇 |
专业分类
安全科学 | 135篇 |
废物处理 | 38篇 |
环保管理 | 201篇 |
综合类 | 439篇 |
基础理论 | 100篇 |
环境理论 | 1篇 |
污染及防治 | 35篇 |
评价与监测 | 50篇 |
社会与环境 | 72篇 |
灾害及防治 | 49篇 |
出版年
2024年 | 2篇 |
2023年 | 12篇 |
2022年 | 18篇 |
2021年 | 23篇 |
2020年 | 23篇 |
2019年 | 29篇 |
2018年 | 17篇 |
2017年 | 24篇 |
2016年 | 30篇 |
2015年 | 28篇 |
2014年 | 37篇 |
2013年 | 48篇 |
2012年 | 65篇 |
2011年 | 68篇 |
2010年 | 70篇 |
2009年 | 66篇 |
2008年 | 37篇 |
2007年 | 65篇 |
2006年 | 76篇 |
2005年 | 48篇 |
2004年 | 52篇 |
2003年 | 47篇 |
2002年 | 40篇 |
2001年 | 32篇 |
2000年 | 39篇 |
1999年 | 34篇 |
1998年 | 16篇 |
1997年 | 13篇 |
1996年 | 15篇 |
1995年 | 17篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有1120条查询结果,搜索用时 46 毫秒
861.
1989~2005年中国启动地震应急预案的研究 总被引:7,自引:1,他引:6
制定地震应急预案是地震应急的行动纲领。过去重“救”轻“防”,而且“救”的程序也缺少规范。地震应急预案将“防、抗、救一作了规范.对每个职能部门的应急工作都作了部署。全国地区(市)级颁布地震预案267个,县级颁布地震预案1603个。据不完全统计,1989-2005年,全国共计启动地震应急预案56次。其中,1989~1993年年均启动0.8次,1994-1998年2.2次,1999-2003年4.2次,2004~2005年10次。 相似文献
862.
Carlos Carroll Reed F. Noss Lindsay M. Dreiss Healy Hamilton Bruce A. Stein 《Conservation biology》2023,37(5):e14075
Comprehensive biodiversity assessments play an essential role in strengthening global and national conservation strategies. The recently announced first U.S. National Nature Assessment (NNA) provides an unparalleled opportunity to comprehensively review status and trends of biodiversity at all levels. This broad context can help in the coordination of actions to conserve individual species and ecosystems. The scientific assessments that informed the Kunming–Montreal Global Biodiversity Framework adopted at the 2022 Convention on Biological Diversity (CBD) conference of parties provide models for synthesizing information on trends at multiple levels of biodiversity, including decline in abundance and distribution of species, loss of populations and genetic diversity, and degradation and loss of ecosystems and their services. The assessments then relate these trends to data on drivers of biodiversity loss and pathways to their mitigation. The U.S. NNA can augment such global analyses and avoid the pitfalls encountered by previous U.S. efforts by ensuring policy-relevant design, data accessibility, and inclusivity in process and product and by incorporating spatial data relevant to national and subnational audiences. Although the United States is not formally a CBD party, an effective NNA should take full advantage of the global context by including indicators adopted at the 2022 meeting and incorporating an independent review mechanism that supports periodic stocktaking and ratcheting up of ambition in response to identified shortfalls in stemming biodiversity loss. The challenges to design of an effective U.S. assessment are relevant globally as nations develop assessments and reporting to support the new global biodiversity framework's targets. By considering and incorporating the diverse ways in which society values and benefits from nature, such assessments can help bridge the gap between research and conservation practice and communicate the extent of the biodiversity crisis to the public, fostering broad-based support for transformative change in humanity's relationship to the natural world. 相似文献
863.
João L. Guilherme Victoria R. Jones Inês Catry Martin Beal Maria P. Dias Steffen Oppel Juliet A. Vickery Chris M. Hewson Stuart H. M. Butchart Ana S. L. Rodrigues 《Conservation biology》2023,37(1):e14002
The conservation of long-distance migratory birds requires coordination between the multiple countries connected by the movements of these species. The recent expansion of tracking studies is shedding new light on these movements, but much of this information is fragmented and inaccessible to conservation practitioners and policy makers. We synthesized current knowledge on the connectivity established between countries by landbirds and raptors migrating along the African–Eurasian flyway. We reviewed tracking studies to compile migration records for 1229 individual birds, from which we derived 544 migratory links, each link corresponding to a species’ connection between a breeding country in Europe and a nonbreeding country in sub-Saharan Africa. We used these migratory links to analyze trends in knowledge over time and spatial patterns of connectivity per country (across species), per species (across countries), and at the flyway scale (across all countries and all species). The number of tracking studies available increased steadily since 2010 (particularly for landbirds), but the coverage of existing tracking data was highly incomplete. An average of 7.5% of migratory landbird species and 14.6% of raptor species were tracked per country. More data existed from central and western European countries, and it was biased toward larger bodied species. We provide species- and country-level syntheses of the migratory links we identified from the reviewed studies, involving 123 populations of 43 species, migrating between 28 European and 43 African countries. Several countries (e.g., Spain, Poland, Ethiopia, Democratic Republic of Congo) are strategic priorities for future tracking studies to complement existing data, particularly on landbirds. Despite the limitations in existing tracking data, our data and results can inform discussions under 2 key policy instruments at the flyway scale: the African–Eurasian Migratory Landbirds Action Plan and the Memorandum of Understanding on the Conservation of Migratory Birds of Prey in Africa and Eurasia. 相似文献
864.
Gabriel Henrique de Oliveira Caetano Reut Vardi Ivan Jarić Ricardo A. Correia Uri Roll Diogo Veríssimo 《Conservation biology》2023,37(5):e14100
The first target of the Convention for Biological Diversity (Aichi target 1) was to increase public awareness of the values of biodiversity and actions needed to conserve it—a key prerequisite for other conservation targets. Monitoring success in achieving this target at a global scale has been difficult; however, increased digitization of human life in recent decades has made it easier to measure people's interests at an unprecedented scale and allows for a more comprehensive evaluation of Aichi target 1 than previously attempted. We used Google search volume data for over a thousand search terms related to different aspects of biodiversity and conservation to evaluate global interest in biodiversity and its conservation. We also investigated the correlation of interest in biodiversity and conservation across countries to variables related to biodiversity, economy, demography, research, education, internet use, and presence of environmental organizations. From 2013 to 2020, global searches for biodiversity components increased, driven mostly by searches for charismatic fauna (59% of searches were for mammal species). Searches for conservation actions, driven mostly by searches for national parks, decreased since 2019, likely due to the COVID-19 pandemic. Economic inequality was negatively correlated with interest in biodiversity and conservation, whereas purchasing power was indirectly positively correlated with higher levels of education and research. Our results suggest partial success toward achieving Aichi target 1 in that interest in biodiversity increased widely, but not for conservation. We suggest that increased outreach and education efforts aimed at neglected aspects of biodiversity and conservation are still needed. Popular topics in biodiversity and conservation could be leveraged to increase awareness of other topics with attention to local socioeconomic contexts. 相似文献
865.
866.
采用美国道化学公司火灾、爆炸危险指数法对某加油站的单个汽油储罐进行了火灾、爆炸危险指数(FEI)评价及安全措施补偿分析.比较了二者的危害等级,结果表明经安全措施补偿,汽油储罐的安全水平得到很大提高. 相似文献
867.
喀什地区生态环境建设中存在的问题与建议 总被引:2,自引:0,他引:2
针对喀什地区近年生态现状日益严竣及生态保护工作存在的问题,为加强生态建设环境保护工作的实效性提出了相关的对策与建议。 相似文献
868.
Community-based approaches to fisheries management has emerged as a mainstream strategy to govern dispersed, diverse and dynamic small scale fisheries. However, amplifying local community led sustainability outcomes remains an enduring challenge. We seek to fill a theoretical gap in the conceptualization of ‘scaling up community-based fisheries management’. We draw on literature of agriculture innovations to provide a framework that takes into account process-driven and structural change occurring across multiple levels of governance, as well as different phases of scaling. We hypothesize that successful scaling requires engagement with all aspects of a governing regime, coalescing a range of actors, and therefore, is an enterprise that is larger than its parts. To demonstrate where the framework offers value, we illustrate the development of community-based fisheries management in Vanuatu according to the framework’s main scaling dimensions. 相似文献
869.
当建筑物出现重大问题或险情时,由构件裂缝的外观和成因对钢筋混凝土结构进行分析和应急评定,可快速、简便地发现事故原因和危险程度,从而为处理工程事故提供定性依据。 相似文献
870.