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   593篇
  免费   12篇
  国内免费   4篇
安全科学   29篇
废物处理   30篇
环保管理   77篇
综合类   53篇
基础理论   154篇
污染及防治   182篇
评价与监测   43篇
社会与环境   31篇
灾害及防治   10篇
  2024年   1篇
  2023年   6篇
  2022年   10篇
  2021年   10篇
  2020年   8篇
  2019年   12篇
  2018年   13篇
  2017年   14篇
  2016年   19篇
  2015年   16篇
  2014年   19篇
  2013年   48篇
  2012年   28篇
  2011年   46篇
  2010年   31篇
  2009年   37篇
  2008年   34篇
  2007年   35篇
  2006年   38篇
  2005年   36篇
  2004年   22篇
  2003年   15篇
  2002年   18篇
  2001年   5篇
  2000年   6篇
  1999年   7篇
  1998年   5篇
  1997年   6篇
  1996年   4篇
  1995年   9篇
  1994年   6篇
  1993年   6篇
  1992年   6篇
  1991年   3篇
  1990年   4篇
  1989年   1篇
  1987年   1篇
  1986年   2篇
  1985年   4篇
  1983年   3篇
  1982年   3篇
  1981年   4篇
  1980年   1篇
  1979年   1篇
  1975年   1篇
  1974年   1篇
  1966年   1篇
  1964年   3篇
排序方式: 共有609条查询结果,搜索用时 156 毫秒
141.
Despite its evolutionary significance, behavioural flexibility of social response has rarely been investigated in insects. We studied a host–social parasite system: the slave-making ant Polyergus rufescens and its host Formica rufibarbis. Free-living host workers from parasitized and from unparasitized areas were compared in their level of aggression against the parasite and alien conspecifics. We expected that a seasonal change would occur in the acceptance threshold of F. rufibarbis workers from a parasitized area towards the parasite, whereas F. rufibarbis workers from an unparasitized area would not show substantial changes connected with the parasites peak in activity (raiding and colony-founding season). The results showed a significant adaptive behavioural flexibility of host species workers and are consistent with the acceptance threshold models (Reeve 1989) prediction that recognition systems are not fixed but context-dependent. In particular, host workers from the unparasitized area were highly aggressive towards the parasite regardless of the season, whereas host workers from the parasitized area significantly increased their aggression towards the parasite during its raiding and colony-founding season. Being able to detect and possibly kill a Polyergus scout searching for host nests can be an effective strategy for a Formica colony to avoid being raided or usurped by a parasite queen.  相似文献   
142.
Over the last decade, adaptive co‐management has been recommended as a policy framework to address complex and uncertain resources management issues. Implementing this theoretical management concept requires the integration of multidisciplinary research and local knowledge. Yet practical protocols to link science, policymaking and societies have yet to be developed. We designed a protocol to produce legitimate, credible and relevant solutions to a regional resources management issue. This is a two‐component protocol. A stakeholder grid categorizes stakeholder representatives in three distinct specialized dialogue arenas: institution representatives, technical experts and local end‐users. An iterative co‐design process then builds on these arenas to assess the institutional legitimacy, technical credibility and empirical relevance dimensions of a common solution initiated by an initial plausible promise. We tested this framework in Réunion to address organic waste management issues at the regional level. The plausible solution explored was the introduction of a recycling industry involved in collecting organic waste and producing and selling organic fertilizers tailored for local crop systems. The protocol application outcomes were consolidated and documented scenarios accepted by all, with knowledge exchange and the broad spread of a stabilized expectation contributing to private initiatives and public policy change.  相似文献   
143.
An in‐well sediment incubator (ISI) was developed to investigate the stability and dynamics of sediment‐associated microbial communities to prevailing subsurface oxidizing or reducing conditions. Herein we describe the use of these devices at the Old Rifle Uranium Mill Tailings Remedial Action (UMTRA) site. During a seven‐month period in which oxidized Rifle Aquifer background sediment (RABS) were deployed in previously biostimulated wells under iron‐reducing conditions, cell densities of known iron‐reducing bacteria, including Geobacteraceae, increased significantly, showing the microbial community response to local subsurface conditions. Phospholipid fatty acid (PLFA) profiles of RABS following in situ deployment were strikingly similar to those of adjacent sediment cores, suggesting ISI results could be extrapolated to the native material of the test plots. Results for ISI deployment with laboratory‐reduced sediments showed only slight changes in community composition and pointed toward the ability of the ISI to monitor microbial community stability and response to subsurface conditions. © 2009 Wiley Periodicals, Inc.  相似文献   
144.
There is now an emerging sense of the scope and nature of response that can be implemented at building and neighbourhood scales to help adapt cities and urban areas to the changing climate. In comparison, the role of larger natural and semi-natural landscapes that surround and permeate cities is less well understood. Addressing this knowledge gap, this paper outlines two case studies that describe and map the flood risk management functions offered by green infrastructure landscapes situated within the Urban Mersey Basin in North West England. The case studies establish that areas potentially exposed to flooding can be located at some distance, and within different jurisdictions, from upstream areas where the flood hazard may be generated and could be moderated via functions provided by green infrastructure landscapes. This raises planning and governance challenges connected to supporting and enhancing flood risk management functions provided by green infrastructure landscapes.  相似文献   
145.
The administration of Jiuzhaigou National Park in Sichuan Province, China, is in the process of considering a range of upgrades to their sanitation and wastewater treatment systems. Their case history involves an ongoing series of engineering design flaws and management failures. The administration of the Park identified sustainability, environmental protection, and education goals for their sanitation and wastewater treatment system. To meet the goal of sustainability, environmental and economic concerns of the Park’s administration had to be balanced with socio-cultural needs. An advanced reconnaissance method was developed that identified reasons for previous failures, conducted stakeholder analysis and interviews, determined evaluation criteria, and introduced innovative alternatives with records of successful global implementations. This evaluation also helped the Park to better define their goals. To prevent future failures, the administration of the Park must commit to a balanced and thorough evaluation process for selection of a final alternative and institute effective long-term management and monitoring of systems. In addition, to meet goals and achieve energy efficient, cost-effective use of resources, the Park must shift their thinking from one of waste disposal to resource recovery. The method and criteria developed for this case study provides a framework to aid in the successful implementation of sanitation projects in both underdeveloped and developed areas of the world, incorporating socio-cultural values and resource recovery for a complex group of stakeholders.  相似文献   
146.
Environmental Science and Pollution Research - Willows, woody plants of genus Salix common in floodplains of temperate regions, act as plant pumps and translocate the Cd and Zn in the soil profiles...  相似文献   
147.
148.
Biodegradation of organic contaminants in groundwater is a microscale process which is often observed on scales of 100s of metres or larger. Unfortunately, there are no known equivalent parameters for characterizing the biodegradation process at the macroscale as there are, for example, in the case of hydrodynamic dispersion. Zero- and first-order degradation rates estimated at the laboratory scale by model fitting generally overpredict the rate of biodegradation when applied to the field scale because limited electron acceptor availability and microbial growth are not considered. On the other hand, field-estimated zero- and first-order rates are often not suitable for predicting plume development because they may oversimplify or neglect several key field scale processes, phenomena and characteristics. This study uses the numerical model BIO3D to link the laboratory and field scales by applying laboratory-derived Monod kinetic degradation parameters to simulate a dissolved gasoline field experiment at the Canadian Forces Base (CFB) Borden. All input parameters were derived from independent laboratory and field measurements or taken from the literature a priori to the simulations. The simulated results match the experimental results reasonably well without model calibration. A sensitivity analysis on the most uncertain input parameters showed only a minor influence on the simulation results. Furthermore, it is shown that the flow field, the amount of electron acceptor (oxygen) available, and the Monod kinetic parameters have a significant influence on the simulated results. It is concluded that laboratory-derived Monod kinetic parameters can adequately describe field scale degradation, provided all controlling factors are incorporated in the field scale model. These factors include advective–dispersive transport of multiple contaminants and electron acceptors and large-scale spatial heterogeneities.  相似文献   
149.
Spatially explicit information on species distributions for conservation planning is invariably incomplete; therefore, the use of surrogates is required to represent broad‐scale patterns of biodiversity. Despite significant interest in the effectiveness of surrogates for predicting spatial distributions of biodiversity, few researchers have explored questions involving the ability of surrogates to incidentally represent unknown features of conservation interest. We used the Great Barrier Reef marine reserve network to examine factors affecting incidental representation of conservation features that were unknown at the time the reserve network was established. We used spatially explicit information on the distribution of 39 seabed habitats and biological assemblages and the conservation planning software Marxan to examine how incidental representation was affected by the spatial characteristics of the features; the conservation objectives (the minimum proportion of each feature included in no‐take areas); the spatial configuration of no‐take areas; and the opportunity cost of conservation. Cost was closely and inversely correlated to incidental representation. However, incidental representation was achieved, even in a region with only coarse‐scale environmental data, by adopting a precautionary approach that explicitly considered the potential for unknown features. Our results indicate that incidental representation is enhanced by partitioning selection units along biophysical gradients to account for unknown within‐feature variability and ensuring that no‐take areas are well distributed throughout the region; by setting high conservation objectives that (in this case >33%) maximize the chances of capturing unknown features incidentally; and by carefully considering the designation of cost to planning units when using decision‐support tools for reserve design. The lessons learned from incidental representation in the Great Barrier Reef have implications for conservation planning in other regions, particularly those that lack detailed environmental and ecological data.  相似文献   
150.
This paper is about improving the viability of discard-reduction pilot projects. One way to address the problem of wasteful discarding of fish at sea is to initiate pilot projects to trial potential solutions, such as selective gear, area closures, discard bans and data enhancement, which could subsequently be adopted by the fishing industry, either voluntarily or through regulation. However, such pilot projects are often difficult both to set up and to sustain through to completion and implementation. This study reviewed 15 discard-related pilot projects to find out what were the most important determinants of their success or lack of it, and to recommend ways in which the prospects of future pilots could be improved. The review identifies the seven most important factors associated with the viability of the pilot projects - fisheries crises; incentivization; funding; expertise; leadership; and enforcement - and shows how fisheries regulators could take steps to reinforce these factors – by faster responses to crises; more incentives and funding; greater use of fishers' knowledge and leadership; and better enforcement mechanisms.  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