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71.
Featured Collection Introduction: Connectivity of Streams and Wetlands to Downstream Waters 下载免费PDF全文
Laurie C. Alexander Ken M. Fritz Kate A. Schofield Bradley C. Autrey Julie E. DeMeester Heather E. Golden David C. Goodrich William G. Kepner Hadas R. Kiperwas Charles R. Lane Stephen D. LeDuc Scott G. Leibowitz Michael G. McManus Amina I. Pollard Caroline E. Ridley Melanie K. Vanderhoof Parker J. Wigington Jr. 《Journal of the American Water Resources Association》2018,54(2):287-297
Connectivity is a fundamental but highly dynamic property of watersheds. Variability in the types and degrees of aquatic ecosystem connectivity presents challenges for researchers and managers seeking to accurately quantify its effects on critical hydrologic, biogeochemical, and biological processes. However, protecting natural gradients of connectivity is key to protecting the range of ecosystem services that aquatic ecosystems provide. In this featured collection, we review the available evidence on connections and functions by which streams and wetlands affect the integrity of downstream waters such as large rivers, lakes, reservoirs, and estuaries. The reviews in this collection focus on the types of waters whose protections under the U.S. Clean Water Act have been called into question by U.S. Supreme Court cases. We synthesize 40+ years of research on longitudinal, lateral, and vertical fluxes of energy, material, and biota between aquatic ecosystems included within the Act's frame of reference. Many questions about the roles of streams and wetlands in sustaining downstream water integrity can be answered from currently available literature, and emerging research is rapidly closing data gaps with exciting new insights into aquatic connectivity and function at local, watershed, and regional scales. Synthesis of foundational and emerging research is needed to support science‐based efforts to provide safe, reliable sources of fresh water for present and future generations. 相似文献
72.
Electric power generating plants that use coal were among the key targets of Title IV of the 1990 Clean Air Act. Under the
first phase of the act, 110 coal-fired electric power plants were required to reduce their sulfur dioxide emissions by 1995
and nitrogen oxide emissions by 1996. Phase 2 of the act requires even greater reduction of sulfur dioxide emissions by 2000
and nitrogen oxide emissions by 2008. This study examines whether the 107 targeted plants (three plants went off-line) have
achieved the desired sulfur dioxide and nitrogen oxide emission levels.
The analysis of sulfur dioxide is based on data from 1990, 1995, and 1999. The findings show that although sulfur oxide increased
by 3% from 1995 to 1999, it decreased by 45% over the 1990–1999 period at the firm level for the targeted firms. The findings
also indicate that the overall reduction in sulfur dioxide was achieved by utilizing low sulfur coal and by purchasing emission
allowances. So far as nitrogen oxides are concerned, there has been a reduction of 14% over the 1990–1999 period, of which
7% was achieved during the 1995–1999 period. An evaluation of emissions at the plant level indicates that several plants do
not meet the emissions level for sulfur dioxide or nitrogen oxides.
These results provide a mixed scorecard for reduction in emissions both for sulfur dioxide and nitrogen oxides. Even though
there is reduction in the emissions on an overall basis at the firm level, several plants that have not been able to reduce
emissions deserve special attention to meet the goals of the act in reducing emissions. 相似文献
73.
Both permit requirements and ecological assessments have been used to evaluate mitigation success. This analysis combines
these two approaches to evaluate mitigation required under Section 404 of the United States Clean Water Act (CWA) and Section
10 of the Rivers and Harbors Act, which allow developers to provide compensatory mitigation for unavoidable impacts to wetlands.
This study reviewed permit files and conducted field assessments of mitigation sites to evaluate the effectiveness of mitigation
required by the US Army Corps of Engineers for all permits issued in Orange County, California from 1979 through 1993. The
535 permit actions approved during this period allowed 157 ha of impacts. Mitigation was required on 70 of these actions,
with 152 ha of enhanced, restored, and created habitat required for 136 ha of impacts. In 15 permit actions, no mitigation
project was constructed, but in only two cases was the originally permitted project built; the two cases resulted in an unmitigated
loss of 1.6 ha. Of the remaining 55 sites, 55% were successful at meeting the permit conditions while 11% failed to do so.
Based on a qualitative assessment of habitat quality, only 16% of the sites could be considered successful and 26% were considered
failures. Thus, of the 126 ha of habitat lost due to the 55 projects, only 26 ha of mitigation was considered successful.
The low success rate was not due to poor enforcement, although nearly half of the projects did not comply with all permit
conditions. Mitigation success could best be improved by requiring mitigation plans to have performance standards based on
habitat functions. 相似文献
74.
Gleason SM Faucette DT Toyofuku MM Torres CA Bagley CF 《Environmental management》2007,40(6):1016-1024
Acting under the auspices of the US Endangered Species Act, we quantified wind erosion and its effects on rare and common
plant species on a semi-arid military installation in Hawaii. Our goal was to develop management strategies, based on local
data, to aid the conservation of rare and common indigenous plants and their habitats. We collected windblown soil coming
off of roads and other disturbed soils to assess likely impacts to plants occurring at certain heights and distances from
disturbed surfaces. We then subjected plants in a glasshouse to windblown dust treatments, designed from our field data to
simulate erosion events, and evaluated the effect of these treatments on photosynthesis and survival. We also designed several
field experiments to examine the in-situ effects of windblown soil and soil substrate on germination, growth rate, and survival
of indigenous and nonindigenous plants. We conclude from these experiments that most direct effects of windblown soil to plants
can be effectively mitigated by locating roads and training areas at least 40 m from sensitive plant habitats and through
vegetation management to maintain at least 11% aerial cover on disturbed surfaces. Effects of soil type on germination, growth,
and survival was species-specific, emphasizing the importance of species trials prior to, or during, rehabilitation efforts. 相似文献
75.
Contaminated stormwater runoff from oil and gas (O&G) operations can pose a significant threat to surface waters. The purpose of this study is to examine the extent of this threat and identify more specific permitting requirements to protect surface waters. To better understand the extent of the threat, this paper identified and characterized the use of waste surface impoundments at O&G facilities as well as the threat level from O&G spills in California. To assess the efficacy of the current federal and California state-permitting regime, the paper evaluated stormwater permit compliance in two California counties. It also reviewed selected spill cases and associated Spill Prevention, Control and Countermeasure Plans and Stormwater Pollution Prevention Plans to identify the adequacy of current industry practices.The analysis showed that contaminated stormwater from O&G facilities can be better regulated. The U.S. Environmental Protection Agency does not require O&G facilities to file for an Industrial Stormwater General Permit even though many O&G industry practices have the potential to contaminate stormwater runoff from the site. When O&G facilities discharge a Reportable Quantity of a hazardous chemical or violate a water quality standard, they are required to enroll in the National Pollutant Discharge Elimination System permit program. Spills, although not a direct indication of stormwater runoff, can highlight polluted runoff discharges that should have been regulated. Medium and large spills that reached waterways were such a risk for which operators did not file for a permit. In California new filing requirements for the oil and gas industry require all facilities that discharge stormwater that has come into contact with any overburden, raw material, or intermediate products located on the site, to file for an Industrial Stormwater General Permit. As this study showed, there has been an increase in enrollment since the enactment of the new requirements. Having all facilities enroll in the general permit program, as done in California, would require minimum monitoring and maintenance that could help prevent spills. A further step to ensure better protocol is to require specific pollution control practices in addition to the current general permit requirements. Such permitting regimes not only can be implemented on the US federal level but also internationally. 相似文献
76.
Sebastian Recknagel Hendrik Radant Regina Kohlmeyer 《Waste management (New York, N.Y.)》2014,34(1):156-161
The objective of this work was to provide updated information on the development of the potential impact of heavy metal containing batteries on municipal waste and battery recycling processes following transposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146 different types of commercially available dry and button cells as well as lithium-ion accumulators for mobile phones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods used for preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a former study or newly developed. Several batteries contained higher mass fractions of mercury or cadmium than the EU limits. Only half of the batteries with mercury and/or lead fractions above the marking thresholds were labelled. Alkaline–manganese mono-cells and Li-ion accumulators, on average, contained the lowest heavy metal concentrations, while zinc–carbon batteries, on average, contained the highest levels. 相似文献
77.
新消防法强化应急救援的立法思考 总被引:1,自引:0,他引:1
赵国勇 《防灾科技学院学报》2009,11(3):80-83
新<消防法>关于应急救援的规定引起了社会各界的普遍关注,本文从立法学角度,从应急救援的立法史,立法背景及立法内容等方面对公安机关消防机构的应急救援职能进行研究,以期准确理解新消防法的立法本意,为有效实施应急救援工作提供理论支持. 相似文献
78.
Abstract: Development of the Northwest Forest Plan (NWFP) was motivated by concerns about the overharvest of late-seral forests and the effects of intensive forest management on the long-term viability of the Northern Spotted Owl ( Strix occidentalis caurina ). Following several years of intense political and legal debates, the final NWFP was approved in 1994. Even though the plan evolved with a broad ecosystem perspective, it remained anchored in the Spotted Owl reserve design proposed in 1990. Based on a criterion of stable or increasing populations, a decade later it remains unclear whether the enactment of the NWFP has improved the conservation status of Spotted Owls. The results of intensive monitoring of several Spotted Owl populations for over a decade suggest a continuing range-wide decline even though rates of timber harvest have declined dramatically on federal lands. The cause of the decline is difficult to determine because the research needed to establish cause and effect relations has not been done. One plausible hypothesis is that the owl's life history greatly constrains its rate of population growth even when habitat is no longer limiting. Since enactment of the NWFP, new threats have arisen, including the movement of Barred Owls ( S. varia ) into the range of the Spotted Owl, political pressure to increase levels of timber harvest, and recent changes to forest laws that eliminate the requirement to assess the viability of wildlife populations on U.S. Department of Agriculture Forest Service lands. At this time is appears that Spotted Owl conservation rests critically on continued implementation of the protections afforded by the NWFP and the U.S. Endangered Species Act. 相似文献
79.
日本政府2015年推出了《食品、农业和农村基本法》的第四次修订,以保证粮食供应和食品安全;推动集约化农业经营,保障农业收入稳定;推动农产品出口和农业技术创新;改善补贴政策,稳定农村人口作为下一阶段日本兴农政策的核心内容。我国农业发展面临许多与日本相似的问题,如农业经营规模小、效率低,务农收入低、人口显著减少等。在我国城镇化和农村劳动力老年化加速的背景下,分析和借鉴日本最新的兴农政策,提出对我国农业政策的若干启示:1以我国近期最新颁布的《食品安全法》和农药残留、化肥实施等国家标准的落实、健全为法制保障基础,推进农业标准化生产和规范化经营管理、建立食品生产全程可追溯机制、加强省县乡三级农产品和食品监测检验能力建设,以尽快提升我国食品安全水平;以培育需求和引导兴趣、技术支持、市场协助建设为手段,激励农户和消费者自主投入生态农业发展。2重点完善国家层面的发展战略统筹和政治、经贸、投资谈判支持,依靠政府的强力支持推动已起步的"一带一路"食品与农业投资发展势头,以壮大我国农产食品出口和农业海外发展。3近期以加强土地流转监管法律政策和财政金融配套扶持政策的建设为主,使支持力度集中于土地实际经营者,以有效提升新型规模化农业经营主体的数量和质量。4将农业补贴由集中于农业生产补贴向兼顾农户收入保障和生态保护、农业发展转移,将农户收入保障形式由财政补贴向保险保障转变,以求农业补贴和保险更高效、长久地兼顾农户收入保障和支持引领农业发展。 相似文献
80.