全文获取类型
收费全文 | 189篇 |
免费 | 5篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 6篇 |
废物处理 | 4篇 |
环保管理 | 38篇 |
综合类 | 30篇 |
基础理论 | 66篇 |
污染及防治 | 39篇 |
评价与监测 | 15篇 |
社会与环境 | 3篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 6篇 |
2013年 | 12篇 |
2012年 | 5篇 |
2011年 | 11篇 |
2010年 | 14篇 |
2009年 | 12篇 |
2008年 | 24篇 |
2007年 | 7篇 |
2006年 | 5篇 |
2005年 | 8篇 |
2004年 | 3篇 |
2003年 | 4篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 8篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1990年 | 3篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1979年 | 2篇 |
1971年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有203条查询结果,搜索用时 234 毫秒
41.
A. H. J. T. Bröcker-Vriends M.D. E. Briët H. H. H. Kanhai E. Bakker J. C. F. M. Dreesen N. J. Leschot J. J. P. van de Kamp P. L. Pearson 《黑龙江环境通报》1988,8(6):411-421
We evaluated the feasibility, reliability, and acceptability of prenatal diagnosis of haemophilia A by DNA analysis of chorionic villi. Twenty-two women at risk to transmit the abnormal gene were referred for prenatal diagnosis, two of them twice. Two of the 22 women appeared to be non-carriers by DNA analysis. In one of these women, the results were known only after chorionic villus sampling had been carried out. Thirteen of the twenty carriers were heterozygous for an intragenic (Bell or Xbal) marker; six women were only heterozygous for the extragenic DXS52 (Stl4) locus. One of the women was homozygous for all the presently known DNA markers within or closely linked with the factor VIII locus. Twelve of the 22 fetuses at risk were male, ten were female. Seven of the 12 male fetuses were shown to be affected and were subsequently aborted. Four male fetuses appeared to be not affected. In one case, the diagnosis was made by use of an extragenic marker. The woman rejected fetal blood sampling to confirm the diagnosis. After birth, a normal factor VIII level was found in three of the four cases. The fourth pregnancy is still continuing. In one of the 12 male fetuses, no diagnosis at the gene level was possible. DNA analysis is expected to provide maximum certainty as to the phenotype of the fetus for approximately 60 per cent of the women; for another 37 per cent a rate of misdiagnosis of 4–5 per cent applies. In only 3 per cent of the cases will no diagnosis at the gene level be possible as yet. The new possibility of a prenatal diagnosis in the first trimester of pregnancy enabled some of these women to have a family of their own and was appreciated in particular by the women who underwent fetoscopy in an earlier pregnancy. 相似文献
42.
Pell EJ Pearson NS Vinten-Johansen C 《Environmental pollution (Barking, Essex : 1987)》1988,53(1-4):171-186
Solanum tuberosum L. cv Norchip plants were grown in open-top chambers in the summer of 1986. Plants were treated with charcoal-filtered air, nonfiltered air, or nonfiltered air supplemented with 33, 66, or 99% of the ambient ozone (O3) concentrations from 1000 to 2000 h eastern daylight time daily. In addition, plants received charcoal-filtered air plus 0, 0.15 (393 microg m(-3)), 0.34 (891 microg m(-3)), or 0.61 (1598 microg m(-3)) ppm sulfur dioxide (SO2) from 0900 to 1200 h once every 14 d for a total of four treatments. Ozone induced a linear reduction in number and weight of Grade One (> 6.35-cm diameter) potato tubers and in total weight of tubers. Ozone also induced linear reductions in the percentage of dry matter of tubers and linear decreases in glucose and fructose content of Grade One tubers. Sulfur dioxide induced a stimulation and then decline of the number, percentage of dry matter, and sucrose content of Grade One tubers. The SO2 response best fit a quadratic curve. No O3 x SO2 interactions were detected for any of the yield or quality functions measured. 相似文献
43.
A time-dependent, 3-dimensional mesoscale model, version 5 (MM5), developed by the Penn State University and the National Center for Atmospheric Research, was applied to study the meteorology over complex terrain of the El Paso-Juarez area. MM5 meteorological output data were compared against experimental data from the Texas Natural Resource Conservation Commission on days of reported high ozone concentrations. Model runs were conducted for a 36-, 12-, 4-km grid arrangement. Results indicate that the dispersion of pollutants by wind plays a significant role on days of low peak ozone concentration. 相似文献
44.
Jonathan Pearson G. Punzo M. Mayfield G. Brighty A. Parsons P. Collins S. Jeavons A. Tagg 《The Environmentalist》2018,38(3):318-329
Flood resilience has been rising up the political, economic and social agendas. Taking an integrated systems approach, using the right design guidance and tools and ensuring that education is in place for all stakeholders are three themes which are intrinsically linked to delivering flood resilience. This paper reviews these themes across the academic research, policy landscape and practitioner approaches, drawing conclusions on the way forward to increase our societies resilience to floods. The term ‘flood resilience’ is being increasingly used, however, it remains to be clearly defined and implemented. The UK, USA and Australia are leading the way in considering what flood resilience really means, but our review has found few examples of action underpinned by an understanding of systems and complexity. This review investigates how performance objectives & indicators are currently interpreted in guidance documents. It provides an in-depth exploration of the methods, that although developed through European and US expertise, can be used for worldwide application. Our analysis highlights that resilience is often embedded in engineering education and frequently linked to risk. This may however, mask the importance of resilience and where it differs from risk. With £2.6 billion to be spent in the UK over the next 6 years on strengthening the country’s flood and coastal defences, this is the opportunity to rethink resilience from a systems approach, and embed that learning into education and professional development of engineers. Our conclusions indicate how consolidating flood resilience knowledge between and within critical infrastructure sectors is the way forward to deliver flood resilience engineering. 相似文献
45.
Historically, small mammals have been focal organisms for studying predator-prey dynamics, principally because of interest in explaining the drivers of the cyclical dynamics exhibited by northern vole, lemming, and hare populations. However, many small-mammal species occur at relatively low and fairly stable densities at temperate latitudes, and our understanding of how complex predator assemblages influence the abundance and dynamics of these species is surprisingly limited. In an intact grassland ecosystem in western Montana, USA, we examined the abundance and dynamics of Columbian ground squirrels (Spermophilus columbianus), deer mice (Peromyscus maniculatus), and montane voles (Microtus montanus) on 1-ha plots where we excluded mammalian and avian predators and ungulates, excluded ungulates alone, or allowed predators and ungulates full access. Our goal was to determine whether the relatively low population abundance and moderate population fluctuations of these rodents were due to population suppression by predators. Our predator-exclusion treatment was divided into two phases: a phase where we excluded all predators except weasels (Mustela spp.; 2002-2005), and a phase where all predators including weasels were excluded (2006-2009). Across the entire duration of the experiment, predator and/or ungulate exclusion had no effect on the abundance or overall dynamics of ground squirrels and deer mice. Ground squirrel survival (the only species abundant enough to accurately estimate survival) was also unaffected by our experimental treatments. Prior to weasel exclusion, predators also had no impacts on montane vole abundance or dynamics. However, after weasel exclusion, vole populations reached greater population peaks, and there was greater recruitment of young animals on predator-exclusion plots compared to plots open to predators during peak years. These results suggest that the impacts of predators cannot be generalized across all rodents in an assemblage. Furthermore, they suggest that specialist predators can play an important role in suppressing vole abundance even in lower-latitude vole populations that occur at relatively low densities. 相似文献
46.
David W. Clow Harrison Forrester Benjamin Miller Heidi Roop James O. Sickman Hodon Ryu Jorge Santo Domingo 《Environmental management》2013,52(6):1400-1414
During 2010–2011, a study was conducted in Sequoia and Kings Canyon National Parks (SEKI) to evaluate the influence of pack animals (stock) and backpackers on water quality in wilderness lakes and streams. The study had three main components: (1) a synoptic survey of water quality in wilderness areas of the parks, (2) paired water quality sampling above and below several areas with differing types and amounts of visitor use, and (3) intensive monitoring at six sites to document temporal variations in water quality. Data from the synoptic water quality survey indicated that wilderness lakes and streams are dilute and have low nutrient and Escherichia coli concentrations. The synoptic survey sites were categorized as minimal use, backpacker-use, or mixed use (stock and backpackers), depending on the most prevalent type of use upstream from the sampling locations. Sites with mixed use tended to have higher concentrations of most constituents (including E. coli) than those categorized as minimal-use (P ≤ 0.05); concentrations at backpacker-use sites were intermediate. Data from paired-site sampling indicated that E. coli, total coliform, and particulate phosphorus concentrations were greater in streams downstream from mixed-use areas than upstream from those areas (P ≤ 0.05). Paired-site data also indicated few statistically significant differences in nutrient, E. coli, or total coliform concentrations in streams upstream and downstream from backpacker-use areas. The intensive-monitoring data indicated that nutrient and E. coli concentrations normally were low, except during storms, when notable increases in concentrations of E. coli, nutrients, dissolved organic carbon, and turbidity occurred. In summary, results from this study indicate that water quality in SEKI wilderness generally is good, except during storms; and visitor use appears to have a small, but statistically significant influence on stream water quality. 相似文献
47.
Bhattarai R Kalita PK Yatsu S Howard HR Svendsen NG 《Journal of environmental management》2011,92(3):803-812
Soil erosion due to water and wind results in the loss of valuable top soil and causes land degradation and environmental quality problems. Site specific best management practices (BMP) are needed to curb erosion and sediment control and in turn, increase productivity of lands and sustain environmental quality. The aim of this study was to investigate the effectiveness of three different types of biodegradable erosion control blankets- fine compost, mulch, and 50-50 mixture of compost and mulch, for soil erosion control under field and laboratory-scale experiments. Quantitative analysis was conducted by comparing the sediment load in the runoff collected from sloped and tilled plots in the field and in the laboratory with the erosion control blankets. The field plots had an average slope of 3.5% and experiments were conducted under natural rainfall conditions, while the laboratory experiments were conducted at 4, 8 and 16% slopes under simulated rainfall conditions. Results obtained from the field experiments indicated that the 50-50 mixture of compost and mulch provides the best erosion control measures as compared to using either the compost or the mulch blanket alone. Laboratory results under simulated rains indicated that both mulch cover and the 50-50 mixture of mulch and compost cover provided better erosion control measures compared to using the compost alone. Although these results indicate that the 50-50 mixtures and the mulch in laboratory experiments are the best measures among the three erosion control blankets, all three types of blankets provide very effective erosion control measures from bare-soil surface. Results of this study can be used in controlling erosion and sediment from disturbed lands with compost mulch application. Testing different mixture ratios and types of mulch and composts, and their efficiencies in retaining various soil nutrients may provide more quantitative data for developing erosion control plans. 相似文献
48.
Increasingly intensive strategies to maintain biodiversity and ecosystem function are being deployed in response to global anthropogenic threats, including intentionally introducing and eradicating species via assisted migration, rewilding, biological control, invasive species eradications, and gene drives. These actions are highly contentious because of their potential for unintended consequences. We conducted a global literature review of these conservation actions to quantify how often unintended outcomes occur and to elucidate their underlying causes. To evaluate conservation outcomes, we developed a community assessment framework for systematically mapping the range of possible interaction types for 111 case studies. Applying this tool, we quantified the number of interaction types considered in each study and documented the nature and strength of intended and unintended outcomes. Intended outcomes were reported in 51% of cases, a combination of intended outcomes and unintended outcomes in 26%, and strictly unintended outcomes in 10%. Hence, unintended outcomes were reported in 36% of all cases evaluated. In evaluating overall conservations outcomes (weighing intended vs. unintended effects), some unintended effects were fairly innocuous relative to the conservation objective, whereas others resulted in serious unintended consequences in recipient communities. Studies that assessed a greater number of community interactions with the target species reported unintended outcomes more often, suggesting that unintended consequences may be underreported due to insufficient vetting. Most reported unintended outcomes arose from direct effects (68%) or simple density-mediated or indirect effects (25%) linked to the target species. Only a few documented cases arose from more complex interaction pathways (7%). Therefore, most unintended outcomes involved simple interactions that could be predicted and mitigated through more formal vetting. Our community assessment framework provides a tool for screening future conservation actions by mapping the recipient community interaction web to identify and mitigate unintended outcomes from intentional species introductions and eradications for conservation. 相似文献
49.
The 2011 flood event in the Mekong Delta: preparedness,response, damage and recovery of private households and small businesses
下载免费PDF全文
![点击此处可从《Disasters》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Floods frequently cause substantial economic and human losses, particularly in developing countries. For the development of sound flood risk management schemes that reduce flood consequences, detailed insights into the different components of the flood risk management cycle, such as preparedness, response, flood impact analyses and recovery, are needed. However, such detailed insights are often lacking: commonly, only (aggregated) data on direct flood damage are available. Other damage categories such as losses owing to the disruption of production processes are usually not considered, resulting in incomplete risk assessments and possibly inappropriate recommendations for risk management. In this paper, data from 858 face‐to‐face interviews among flood‐prone households and small businesses in Can Tho city in the Vietnamese Mekong Delta are presented to gain better insights into the damage caused by the 2011 flood event and its management by households and businesses. 相似文献
50.
Spatial-econometric analysis of attraction and repulsion of private conservation by public reserves 总被引:1,自引:0,他引:1
Heidi J. Albers Amy W. Ando Xiaoxuan Chen 《Journal of Environmental Economics and Management》2008,56(1):33-49
It is difficult for public agencies to make optimal reserve-site selections without knowing how new public reserves might influence the configuration of private conservation. Private land trusts protect much land in the USA, but little is known about how private groups respond to conservation decisions made by other conservation agents. To fill that gap, we analyze township-level spatial data on conservation in California, Illinois, and Massachusetts to explore relationships between the location of private and public conservation land. Using linear spatial-econometric models and Bayesian spatial probit models, we find evidence that private-protected acres are clustered together in space. In California, it appears that private land conservation is attracted towards places where the government has reserves. In Illinois and Massachusetts, however, it appears that private conservation shifts away from townships with government reserves due to a mixture of spatial repulsion and simple acreage displacement. 相似文献