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631.
广州市水政水资源管理信息系统开发研究 总被引:2,自引:0,他引:2
广州市水政水资源管理信息系统是一个基于GIS技术的、客户/服务器结构下的环境信息系统,本文介绍了系统的总体设计与关键技术,该系统是为水资源主管部门进行水资源日常管理而设计的,目的是为了提高水资源管理的科学化,现代化水平,系统开发的关键技术要有服务器数据库建设、客户端与服务器的数据连接以及组件式GIS(MapObjects)的应用。 相似文献
632.
生态移民是把生态环境脆弱地区的人口有计划、有组织地异地搬迁安置,从而达到人口、资源、环境和经济社会的协调发展,是我国实施环境保护基本国策的重要措施之一.通过研究我国的生态移民政策及其实施现状,在分析目前存在的困难和问题的基础上,提出实施生态移民工程所要完善研究的内容和政策措施,以期能够保证我国生态移民工作的顺利推进. 相似文献
633.
Lance A. Waller Brett J. Goodwin Mark L. Wilson Richard S. Ostfeld Stacie L. Marshall Edward B. Hayes 《Environmental and Ecological Statistics》2007,14(1):83-100
We present an exploratory analysis of reported county-specific incidence of Lyme disease in the northeastern United States
for the years 1990–2000. We briefly review the disease ecology of Lyme disease and the use of risk maps to describe local
incidence as estimates of local risk of disease. We place the relevant elements of local environmental and ecological variables,
local disease incidence, and (importantly) local disease reporting in a conceptual context to frame our analysis. We then
apply hierarchical linear models of increasing complexity to summarize observed patterns in reported incidence, borrowing
information across counties to improve local precision. We find areas of increasing incidence in the central northeastern
Atlantic coast counties, increasing incidence branching to the north and west, and an area of fairly stable and slightly decreasing
reported incidence in western New York. 相似文献
634.
Katharina Rietig 《环境政策》2019,28(2):228-247
ABSTRACTEuropean climate policy faced increasing constraints during the economic and Eurozone crises (2008–2014). The European Commission subsequently refocused policymaking toward integrating climate objectives into other policy areas such as energy and the 2014–2020 European Union (EU) budget. The conditions for successful climate policy integration (CPI) are analyzed, focusing on the compatibility of key actors’ beliefs. In renewable energy policy, CPI was successful as long as the co-benefits and related policy-core beliefs of energy security, rural economic development and climate action coexisted harmoniously. Once conflict among these policy-core beliefs emerged during the biofuels controversy, CPI was weakened as actors with competing economy-focused beliefs controlled the decision-making process. The case of EU budget climate mainstreaming illustrates how actors can add climate objectives into legislation despite meaningful discussion being ‘crowded out’ by other priorities. The findings highlight the importance of low conflict between departments, compatible beliefs and policy priorities for successful CPI. 相似文献
635.
ABSTRACTPolicy evaluation has grown significantly in the EU environmental sector since the 1990s. In identifying and exploring the putative drivers behind its rise – a desire to learn, a quest for greater accountability, and a wish to manipulate political opportunity structures – new ground is broken by examining how and why the existing literatures on these drivers have largely studied them in isolation. The complementarities and potential tensions between the three drivers are then addressed in order to advance existing research, drawing on emerging empirical examples in climate policy, a very dynamic area of evaluation activity in the EU. The conclusions suggest that future studies should explore the interactions between the three drivers to open up new and exciting research opportunities in order to comprehend contemporary environmental policy and politics in the EU. 相似文献
636.
Diarmuid Torney 《环境政策》2019,28(6):1124-1144
ABSTRACTThe past decade has seen the introduction of framework climate change laws in several countries. The development of climate laws in two small European states, Ireland and Finland, both of which introduced national climate laws in 2015, are examined. Two questions are addressed. First, to what extent do later adopters of climate policy instruments draw on the examples of pioneering legislation? Second, how and why are pioneering climate policy instruments modified by later adopters? In both cases, the 2008 UK Climate Change Act was a source of inspiration in the early stages, particularly for civil society campaigns. Thereafter, domestic interests mobilised to remove from legislative proposals the most pioneering and ambitious parts of the UK model. The result, in both cases, was enactment of climate laws that resembled only very loosely the UK Climate Change Act. 相似文献
637.
638.
F. Veloso-Gomes F. Taveira-Pinto Luciana das Neves Joaquim Pais Barbosa Carlos Coelho 《Journal of Coastal Conservation》2004,10(1):43-52
The entire northwestern coast of Portugal is undergoing severe erosion and there are several areas at high risk of erosion.
Commonly considered as a problem—because it jeopardizes human development along the coast—erosion is indeed a natural process
of sediment redistribution. This paper presents a brief analysis of erosion driving forces and the subsequent state of vulnerability
that coastal segments between the mouth of the River Douro and Cape Mondego are facing. The paper also discusses erosion risk
levels, low or high, and the subsequent questions whether there are populations, economical assets or natural habitats at
risk and/or areas prone to coastal flooding. Main challenges and future trends along the study area are identified in the
light of understanding the underlying causes of conflicts and what realistically can be achieved given the morphodynamics
and hydrodynamic processes, human development established along this coastal segment and the existing policies. 相似文献
639.
The role of turbidity as a constraint on predator-prey interactions in aquatic environments 总被引:4,自引:0,他引:4
Many of the world's most productive aquatic ecosystems usually contain turbid water. Paradoxically, many fish species that
live in these habitats are also those that often rely on vision to detect their predators and their prey. For these fish,
turbidity will reduce the distance at which predator-prey interactions occur, and there should be a reduction in the opportunity
for behavioural modification to control the risk of predation. Under these conditions, we predict that most antipredator behaviour
will become ineffective and that predator-prey interactions in turbid water will be primarily characterised by the direct
effects of predator consumption of prey, rather than behavioural modification reducing the growth rates of prey. This hypothesis
was tested in two laboratory experiments. The first experiment investigated how water turbidity, risk of predation, and their
interaction affect habitat choice decisions by fathead minnows (Pimephales promelas). These data demonstrate that fathead minnows reduce their use of dangerous habitats, but that this effect is diminished
in turbid water. A second experiment examined mortality patterns when these fish were preyed upon by yellow perch (Perca flavescens) in clear and turbid water. Absolute mortality rates were unaffected by visibility, but patterns of mortality were random
in turbid water and skewed towards smaller individuals in clear water. Combined, these results support our hypothesis and
suggest that the impact of predation risk will be reduced in turbid aquatic ecosystems.
Received: 23 May 1996 / Accepted after revision: 18 November 1996 相似文献
640.
Abstract: Policy aimed at conserving biodiversity has focused on species diversity. Loss of genetic diversity, however, can affect population persistence, evolutionary potential, and individual fitness. Although mammals are a well-studied taxonomic group, a comprehensive assessment of mammalian genetic diversity based on modern molecular markers is lacking. We examined published microsatellite data from populations of 108 mammalian species to evaluate background patterns of genetic variability across taxa and body masses. We tested for loss of genetic diversity at the population level by asking whether populations that experienced demographic threats exhibited lower levels of genetic diversity. We also evaluated the effect of ascertainment bias (a reduction in variability when microsatellite primers are transferred across species) on our assessment of genetic diversity. Heterozygosity did not vary with body mass across species ranging in size from shrews to whales. Differences across taxonomic groupings were noted at the highest level, between populations of marsupial and placental mammals. We documented consistently lower heterozygosity, however, in populations that had experienced demographic threats across a wide range of mammalian species. We also documented a significant ( p = 0.01) reduction in heterozygosity as a result of ascertainment bias. Our results suggest that populations of both rare and common mammals are currently losing genetic diversity and that conservation efforts focused above the population level may fail to protect the breadth of persisting genetic diversity. Conservation policy makers may need to focus their efforts below the species level to stem further losses of genetic resources. 相似文献