首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   442篇
  免费   25篇
  国内免费   26篇
安全科学   38篇
废物处理   1篇
环保管理   92篇
综合类   126篇
基础理论   60篇
环境理论   4篇
污染及防治   13篇
评价与监测   8篇
社会与环境   21篇
灾害及防治   130篇
  2023年   8篇
  2022年   11篇
  2021年   17篇
  2020年   17篇
  2019年   17篇
  2018年   19篇
  2017年   15篇
  2016年   26篇
  2015年   26篇
  2014年   9篇
  2013年   33篇
  2012年   16篇
  2011年   23篇
  2010年   23篇
  2009年   20篇
  2008年   13篇
  2007年   23篇
  2006年   28篇
  2005年   21篇
  2004年   12篇
  2003年   17篇
  2002年   15篇
  2001年   13篇
  2000年   18篇
  1999年   13篇
  1998年   3篇
  1997年   5篇
  1996年   6篇
  1995年   6篇
  1994年   7篇
  1992年   3篇
  1991年   2篇
  1990年   1篇
  1987年   2篇
  1984年   1篇
  1983年   2篇
  1981年   1篇
  1980年   1篇
排序方式: 共有493条查询结果,搜索用时 234 毫秒
211.
The paper industry's climate change gas emissions are growing. This article considers how to reduce emissions from cut-size office paper by bypassing stages in its life cycle. The options considered are: incineration, which cuts out landfill; localisation, which cuts out transport; annual fibre, which cuts out forestry and reduces pulping; fibre recycling, which cuts out landfill, forestry and pulping; un-printing, which cuts out all stages except printing; electronic-paper, which cuts out all stages. Un-printing may offer the greatest climate change emission reduction. There are uncertainties in this result, particularly in estimating the proportion of waste office paper would be suitable for un-printing.  相似文献   
212.
本文对编制唐山市灾害源分布、综合成灾模型及对策管理程序的功能和总框图给予了简要说明,并结合唐山市各种灾害的情况阐述了该程序建立各部分的子框图的重要性和关键技术。  相似文献   
213.
NGO initiatives in risk reduction: an overview   总被引:2,自引:0,他引:2  
Benson C  Twigg J  Myers M 《Disasters》2001,25(3):199-215
NGOs appear to be well placed to play a significant role in natural disaster mitigation and preparedness (DMP), working, as they do, with poorer and marginalised groups in society. However, there is little information on the scale or nature of NGO DMP activities. This paper reports the findings of a study seeking to address that gap. It confirms that NGOs are involved in a diverse range of DMP activities but that a number of them are not labelled as such. Moreover, evidence of the demonstrable quality and benefits of DMP involvement is poor. The paper concludes that a number of problems need to be overcome before DMP can be satisfactorily mainstreamed into NGO development and post-disaster rehabilitation programmes. However, there are some early indications of momentum for change.  相似文献   
214.
臭氧污染对我国粮食安全影响及其减缓应对措施   总被引:1,自引:0,他引:1  
近年来不断扩大和加重的臭氧(O3)污染,越来越受到社会各界的高度关注.基于国内外O3对农作物产量影响的相关研究结果,本文综合分析了O3对我国主要农作物产量的影响程度及其区域分布.结果表明:我国部分地区严重的空气O3污染,已经造成主要粮食作物(如小麦、水稻、玉米和大豆等)产量损失,特别是小麦产量损失可达10%以上.O3对我国粮食产量造成损失最大的地区集中在我国东部,尤其是黄淮海平原的小麦产量损失最为严重.因此,从保障我国粮食安全角度,应该加强O3对农作物生产影响模拟实验和科学评估研究.在开展O3污染防控的同时,应该积极推广减缓O3对农作物危害的政策和技术措施.  相似文献   
215.
We present the first community‐level study of the associations of both roads and other human disturbances with the distribution of mammals in Gabon (central Africa). Our study site was in an oil concession within a littoral mosaic landscape. We conducted surveys along 199 line transects and installed camera traps on 99 of these transects to document mammal presence and abundance. We used generalized linear mixed‐effect models to document associations between variables related to the ecosystem (land cover, topography, and hydrology), roads (coating, width of rights of way, condition, type of vehicle used on the road, traffic level, affiliation of users, and general type of road), and other human disturbances (urbanization, agriculture, hunting, logging, gathering, and industrial activities) and the abundance or presence of 17 species or groups of mammals including elephant (Loxodonta cyclotis), buffalo (Syncerus caffer), sitatunga (Tragelaphus spekei), red river hog (Potamochoerus porcus), smaller ungulates, gorilla (Gorilla gorilla), chimpanzee (Pan troglodytes), side‐striped jackal (Canis adustus), carnivores, monkeys, and large rodents. Some types of roads and other human disturbances were negatively associated with the abundance or presence of elephants, buffalos, gorillas, sitatungas, some monkeys, and duikers. The pattern of associations of mammals with roads and other human disturbances was diverse and included positive associations with road presence (red river hog, some monkeys, and duikers), agriculture (sitatunga, small carnivores, and large rodents) and industrial activities (sitatunga, red river hog, red duikers, and side‐striped jackal). Our results suggest that the community of mammals we studied was mostly affected by hunting, agriculture, and urbanization, which are facilitated by road presence. We recommend increased regulation of agriculture, hunting, and road building in the area. Distribución de una Comunidad de Mamíferos en Relación a Carreteras y Otras Perturbaciones Humanas en Gabón, Africa Central  相似文献   
216.
Translocations are an important tool for wildlife conservation, although progress in the field of reintroduction biology has been hindered by the ad hoc and opportunistic nature of many translocations. We used an experimental translocation to elucidate the role of raccoon roundworm (Baylisascaris procyonis) and inbreeding depression in the decline of the Allegheny woodrat (Neotoma magister), an endangered species. We translocated woodrats from genetically diverse populations in the core of the species range to 4 previously occupied sites (reintroductions) and 2 sites supporting genetically depauperate populations (reinforcements) in Indiana (U.S.A.). In 2 reintroduction sites and 1 reinforcement site, we distributed anthelmintic baits to passively deworm raccoons and reduce the risk of woodrat exposure to roundworms. The remaining sites served as controls. We used raccoon latrine surveys and fecal flotation to monitor temporal variability in roundworm prevalence and effect of treatment. We used live trapping and microsatellite genotyping to monitor the demographic and genetic response of translocated populations over the following 54 months. At the conclusion of the study, 4 of 6 translocations were successfully maintaining abundance through local recruitment. The distribution of anthelmintic baits reduced levels of roundworm contamination, but levels of contamination were also low in 2 of 3 control sites. Reintroductions failed at control sites, one of which was due to high roundworm exposure. The other failed control reintroduction was likely attributable to demographic stochasticity and limited reproductive potential following initial mortality within the first 4 months. In both control and treatment reinforcements, increases in both allelic richness and heterozygosity were accompanied by increases in abundance, which is suggestive of genetic rescue. Our results demonstrate that mitigation of roundworm exposure through the distribution of anthelmintic baits can facilitate woodrat recovery and that diversity within genetically depauperate populations can be restored through the introduction of a limited number of individuals. El Uso de Reubicaciones Experimentales de Neotoma magister para Descifrar Agentes Causales de Disminución  相似文献   
217.
A Generic Impact-Scoring System Applied to Alien Mammals in Europe   总被引:1,自引:0,他引:1  
Abstract: We present a generic scoring system that compares the impact of alien species among members of large taxonomic groups. This scoring can be used to identify the most harmful alien species so that conservation measures to ameliorate their negative effects can be prioritized. For all alien mammals in Europe, we assessed impact reports as completely as possible. Impact was classified as either environmental or economic. We subdivided each of these categories into five subcategories (environmental: impact through competition, predation, hybridization, transmission of disease, and herbivory; economic: impact on agriculture, livestock, forestry, human health, and infrastructure). We assigned all impact reports to one of these 10 categories. All categories had impact scores that ranged from zero (minimal) to five (maximal possible impact at a location). We summed all impact scores for a species to calculate "potential impact" scores. We obtained "actual impact" scores by multiplying potential impact scores by the percentage of area occupied by the respective species in Europe. Finally, we correlated species’ ecological traits with the derived impact scores. Alien mammals from the orders Rodentia, Artiodactyla, and Carnivora caused the highest impact. In particular, the brown rat (Rattus norvegicus), muskrat (Ondathra zibethicus), and sika deer (Cervus nippon) had the highest overall scores. Species with a high potential environmental impact also had a strong potential economic impact. Potential impact also correlated with the distribution of a species in Europe. Ecological flexibility (measured as number of different habitats a species occupies) was strongly related to impact. The scoring system was robust to uncertainty in knowledge of impact and could be adjusted with weight scores to account for specific value systems of particular stakeholder groups (e.g., agronomists or environmentalists). Finally, the scoring system is easily applicable and adaptable to other taxonomic groups.  相似文献   
218.
The optimal level of investment in mitigation strategies is usually difficult to ascertain in the context of disaster planning. This research develops a model to provide such direction by relying on cost of quality literature. This paper begins by introducing a static approach inspired by Joseph M. Juran's cost of quality management model (Juran, 1951) to demonstrate the non‐linear trade‐offs in disaster management expenditure. Next it presents a dynamic model that includes the impact of dynamic interactions of the changing level of risk, the cost of living, and the learning/investments that may alter over time. It illustrates that there is an optimal point that minimises the total cost of disaster management, and that this optimal point moves as governments learn from experience or as states get richer. It is hoped that the propositions contained herein will help policymakers to plan, evaluate, and justify voluntary disaster mitigation expenditures.  相似文献   
219.
《Environmental Hazards》2013,12(3-4):258-277
Flood risk has increased in France in the last 20 years and is projected to increase further in the future due to climate change and increase in exposure. Since 1982, France has had a natural disasters insurance system (‘CatNat’) in place that covers flood damage. This insurance system has been combined with what are called ‘Risk Prevention Plans’ (PPRs) in order to stimulate the undertaking of flood risk mitigation measures by communities and households. However, these schemes do not provide optimal incentives for flood damage reduction. This is confirmed by the results from a survey about flood preparedness of 885 households who live in flood-prone areas in France, which are presented in this paper. Moreover, this study provides suggestions for improvement, which are assessed on their potential economic, social and political implications. Among these suggestions are increasing the effectiveness of PPRs and increasing the incentives to apply and implement PPRs; improving the monitoring of the implementation of damage mitigation measures; and the possibility to differentiate premiums and deductibles according to flood risk.  相似文献   
220.
ABSTRACT

In an effort to understand the social-physical vulnerabilities from the 2008 Wenchuan earthquake, this research established and validated a conceptual model for natural disaster analysis. The earthquake severely impacted the built environment, with many buildings being destroyed in the earthquake and from secondary impacts. This vulnerable environment exacerbated the poverty in the local residents because of the lack of flat land and the inaccessibility of the mountainous areas. Therefore, there was an interactive relationship between the built environment vulnerability and the social vulnerability. Due to general poverty and low education levels, social vulnerability in rural areas is often the result of poor quality building construction; in the event of an earthquake, therefore, most economic losses and casualties are the result of building destruction. To enhance social-physical resilience, measures should be adopted to mitigate the vulnerability of the built environment and society through actions such as land use planning, the use of seismic-resistant technologies, and investment in infrastructure, education, industrial development, and environmental protection. This research extracts the reasons for the vulnerabilities through an examination of the interactions between the natural environment, the built environment, and the local society. The insights gained have significant theoretical and practical implications in assisting vulnerable communities resist and adapt to natural hazards to achieve sustainable development.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号