全文获取类型
收费全文 | 1299篇 |
免费 | 41篇 |
国内免费 | 103篇 |
专业分类
安全科学 | 160篇 |
废物处理 | 12篇 |
环保管理 | 465篇 |
综合类 | 257篇 |
基础理论 | 216篇 |
环境理论 | 3篇 |
污染及防治 | 142篇 |
评价与监测 | 71篇 |
社会与环境 | 64篇 |
灾害及防治 | 53篇 |
出版年
2023年 | 8篇 |
2022年 | 27篇 |
2021年 | 32篇 |
2020年 | 40篇 |
2019年 | 34篇 |
2018年 | 29篇 |
2017年 | 35篇 |
2016年 | 57篇 |
2015年 | 44篇 |
2014年 | 45篇 |
2013年 | 98篇 |
2012年 | 45篇 |
2011年 | 79篇 |
2010年 | 39篇 |
2009年 | 71篇 |
2008年 | 66篇 |
2007年 | 74篇 |
2006年 | 58篇 |
2005年 | 43篇 |
2004年 | 47篇 |
2003年 | 54篇 |
2002年 | 34篇 |
2001年 | 35篇 |
2000年 | 39篇 |
1999年 | 33篇 |
1998年 | 26篇 |
1997年 | 19篇 |
1996年 | 20篇 |
1995年 | 18篇 |
1994年 | 19篇 |
1993年 | 21篇 |
1992年 | 13篇 |
1991年 | 18篇 |
1990年 | 6篇 |
1989年 | 9篇 |
1988年 | 12篇 |
1987年 | 9篇 |
1986年 | 10篇 |
1985年 | 4篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 7篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1972年 | 10篇 |
1971年 | 8篇 |
1970年 | 4篇 |
排序方式: 共有1443条查询结果,搜索用时 15 毫秒
941.
Environmental management systems and sustainable development 总被引:1,自引:0,他引:1
The idea of sustainable development was first brought to widespread attention as a global issue; however, it is increasingly being applied at more local levels down to that of individual companies. This raises the potential danger that sustainable development will come to be predominantly identified with the preservation of the organisation involved. A likely outcome is that management decision-making will tip the balance too far in favour of people-centred interests as against environmental interests. An initial step in preventing this is to make any bias in the balance of interests transparent to management. To do this, a model of sustainability is set up in terms that provide a context for the implementation of a quality based environmental management system such as that specified by the International Standard, ISO 14001. In response to inherent uncertainty, a precautionary approach is adopted. The implications of this model for the structuring of critical environmental management system elements are then discussed and a way to generate an indicator of bias proposed. The content of an audit, which would measure the extent to which an organisation has a management system competent to measure and monitor this bias, is also discussed and proposed as another useful indicator. 相似文献
942.
France Lamy John Bolte Mary Santelmann Courtland Smith 《Journal of the American Water Resources Association》2002,38(2):517-529
ABSTRACT: Making decisions for environmental management is a complex task due to the multiplicity and diversity of technological choices. Furthermore, the exploitation of natural resources and the preservation of the natural environment imply objectives that are often in conflict within a sustainable development paradigm. Managers and other decision makers require techniques to assist them in understanding strategic decision making. This paper illustrates the use of a multiple‐objective decision‐making methodology and an integrative geographical information system‐based decision‐making tool developed to help watershed councils prioritize and evaluate restoration activities at the watershed level. Both were developed through a multidisciplinary approach. The decision‐making tool is being applied in two watersheds of Oregon's Willamette River Basin. The results suggest that multiple‐objective methods can provide a valuable tool in analyzing complex watershed management issues. 相似文献
943.
智能交通与中国的交通安全 总被引:3,自引:4,他引:3
在交通运输中 ,安全是最重要的因素。近年来 ,中国交通运输事业的快速发展 ,给人民的生活带来诸多便利 ,但当前的交通安全状况却不容乐观 ,交通事故频繁发生 ,事故死亡人数逐年上升。智能交通系统是一个高科技集成系统 ,它综合运用各种高新技术于整个交通管理系统之中 ,可以系统、全面、高效地提高交通运输的安全性。笔者研究了我国的交通安全问题 ,尤其是公路交通安全问题 ,阐明了如何应用智能交通系统 ,有效地减少交通事故 ,改善交通安全状况 ;指出了我国发展智能交通对于改善交通安全 ,解决交通安全问题的重要意义并展望了我国发展智能交通的前景 相似文献
944.
Daniel P. Loucks 《Journal of the American Water Resources Association》1995,31(4):571-582
ABSTRACT: Computer-based models together with their interactive interfaces are typically called decision support systems. DSSs are interactive computer-based information providers. The common objective of all DSSs, regardless of the frameworks, methodologies, or techniques used, is to provide timely information that supports human decision makers - at whatever level of decision making. The informational needs of the decision making process are the key considerations that motivate the development of DSSs. The growth of DSS development and use has been substantial. In spite of this impressive growth, computer-aided decision support systems can still be improved and made more useful to those they are intended to support. Researchers and practitioners, and indeed the computer industry, continue to identify ways of doing this. This paper reviews some of these needs and opportunities by focusing on the process of successful DDS development and implementation. The paper outlines an approach and some guidelines for developing DSSs. The approach emphasizes and requires considerable interaction between the DSS developers (analysts) and the DSS users (decision makers). This interaction and feedback is required throughout the entire DSS building, testing and evaluation (debugging), and implementation processes. The paper concludes by identifying some research needs and opportunities affecting DSS development and effective use. 相似文献
945.
Graham A. Tobin 《Journal of the American Water Resources Association》1995,31(3):359-367
ABSTRACT: A history of flood control in the United States shows an undying affair with levees. This love affair, however, was put severely to the test by the record flooding in the summer of 1993. About 70 percent of levees in the upper Midwest failed during this time, leading to extensive damage to both farmland and urban areas. Consequently, there were repeated calls to re-assess the nation's floodplain management policies. The report of the Intera-gency Floodplain Management Review Committee is one outcome of this and it forms the basis of this commentary on levees. In many respects, levees are effective flood control measures, being relatively cheap to implement and easy to build. At the same time, levees have negative impacts, affecting the hydrological regime both up and down stream, and often exacerbating flooding in other places. Furthermore, technical weaknesses in design, planning, construction, and maintenance have all contributed to levee failures. While the report recommends changes in floodplain management to address some of these issues, it is difficult to see how these will materialize given the current political, economic, and social climate. 相似文献
946.
Mark B. Bain 《Environmental management》1993,17(2):211-224
Introduced species have created environmental benefits and unanticipated disasters so a priori assessments of species introductions
are needed for environmental management. A checklist for assessing impacts of introduced species was developed from studies
of introduced species and recommendations for planning introductions. Sterile, triploid grass carp (Ctenopharyngodon idella) are just beginning to be used as a biocontrol agent for the management of aquatic vegetation in open waterways. Potential
impacts of grass carp in open systems were identified by reviewing grass carp biology relative to the impact assessment checklist.
The potential consequences of introduced grass carp were reviewed for one case study. The case study demonstrated that conclusions
about potential impacts and monitoring needs can be made despite incomplete information and uncertainty.
Indicators of environmental impact and vulnerability of host systems were grouped into six categories: population control,
hybridization, diseases and parasites, habitat alterations, biological effects, and management issues. Triploid grass carp
can significantly alter habitat and biological resources through the secondary effects of reductions in aquatic vegetation.
Potential impacts and significant uncertainties involve fish dispersions from plant control areas, inability to control vegetation
loss, loss of diverse plant communities and their dependent species, and conflicts with human use of the water resource. Adequate
knowledge existed to assess most potential consequences of releasing large numbers of triploid grass carp in Guntersville
Reservoir, Alabama. However, the assessment of potential impacts indicated that moderate, incremental stockings combined with
monitoring of vegetation and biological resources are necessary to control the effects of grass carp and achieve desirable,
intermediate plant densities.
Cooperators: Auburn University (Alabama Agricultural Experiment Station, Department of Fisheries and Allied Aquacultures,
Department of Zoology and Wildlife Sciences), US Fish and Wildlife Service, Alabama Game and Fish Division, and the Wildlife
Management Institute. 相似文献
947.
A newly installed combined detention/wetland stormwater treatment facility upstream from Lake McCarrons, Roseville, Minnesota,
was monitored for 21 months to evaluate its effectiveness and the response of the lake to decreased phosphorus loads. The
treatment facility consists of a 1.0-ha detention pond that discharges into a series of six constructed wetland “chambers.”
Data from snowmelt and rainfall events are presented for several pollutants. Results show good reductions for most pollutants.
Discussion on the facets of the system's operation are presented. Data from the lake show very little change in its water
quality from three years prior to restoration (1984–1986) to three years following restoration (1987–1989): the lake's phosphorus
and chlorophyll has actually increased. 相似文献
948.
Pohchin Lai 《Environmental management》1990,14(1):73-80
Geographic information systems (GIS) technology is altering the work environment for planning and decision-making tasks. This
article is an account of a resource application that make use of the GIS technology. It provides some cost estimates and reasons
for the fairly slow development toward an integrated resource data base for environmental planning and management. It tries
to identify some of the constraints of such an integrated data-base approach toward environmental assessment. 相似文献
949.
Administrative machinery has been set up to regulate and control most of the emissions that are known to have severe local
consequences, such as the discharge of raw sewage into rivers and lakes and the smokestack emission of air pollutants. Now,
the nature of environmental degradation is usually different. We are faced with pollutants and effects with more subtle cause-effect
relationships, often characterized by larger geographic areas of interest and longer term potential damage; the potential
risk is now more chronic than acute. Acid rain and climate change are good examples, in that they are associated with a variety
of pollutants from a number of sources and damage to ecosystems occurs over many years. It is argued that monitoring programs
should evolve to reflect the changing nature of the environmental problems they are addressing. It is now necessary to consider
interactions among many pollutants, mixing among the various media, and potentially affecting many components of the ecosystem
in both indirect and direct ways. Here, integrated monitoring and analysis is presented as a unifying strategy to bring together
different measurement methodologies in different disciplines, addressing environmental questions of complexity beyond the
scope of many existing activites that have a classical narrower focus. The underlying concept is of nested networks, each
tier being composed of sites selected for specific purposes but arranged to maximize the number of common sites where more
multidisciplinary questions can be addressed. 相似文献
950.
G. Mathias Kondolf 《Environmental management》1994,18(4):501-509
The North Fork of Cottonwood Creek, in the White Mountains, Inyo National Forest, California, is a critically important refuge
for the Paiute cutthroat trout (Oncorhynchus clarki seleniris), a federally listed threatened species. Habitat for these fish appears to be limited by excessive levels of fine sediment
in the channel, and livestock grazing of riparian meadows has been implicated in delivery of sediment to the channel. However,
the relationships between land use and sediment yield have not been conclusively determined, in large part because there are
no historically ungrazed sites to serve as long-term controls. Accordingly, land-use decisions must be made under scientific
uncertainty. To reduce erosion and sedimentation in the stream, the Forest Service spent approximately US$260,000 from 1981
to 1991 to repair watershed damage from livestock grazing, prevent livestock from traversing steep banks, and limit livestock
access to the channel. Throughout this period, livestock grazing has continued on these lands, yielding less than $12,000
in grazing fees. In revising its Allotment Management Plan for the basin, the Forest Service rejected the “no-grazing” alternative
because it was inconsistent with its Land and Resource Management Plan, which specifies there is to be no net reduction of
grazing.
Joint appointment with the University of California White Mountain Research Station, East Line Street, Bishop, California
93518, USA. 相似文献