全文获取类型
收费全文 | 120篇 |
免费 | 1篇 |
专业分类
安全科学 | 1篇 |
废物处理 | 8篇 |
环保管理 | 23篇 |
综合类 | 23篇 |
基础理论 | 21篇 |
污染及防治 | 26篇 |
评价与监测 | 17篇 |
社会与环境 | 2篇 |
出版年
2019年 | 1篇 |
2018年 | 2篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 4篇 |
2013年 | 6篇 |
2012年 | 4篇 |
2011年 | 5篇 |
2010年 | 5篇 |
2009年 | 3篇 |
2007年 | 9篇 |
2006年 | 12篇 |
2005年 | 4篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 5篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1970年 | 2篇 |
1967年 | 1篇 |
排序方式: 共有121条查询结果,搜索用时 31 毫秒
31.
Summary. Young larvae of Adalia bipunctata search an area more intensively when exposed to the odour from other larvae feeding on aphids than when exposed only to the
odour of aphids. In an olfactometer young larvae were significantly attracted either to the odour of crushed aphids or larvae
feeding on aphids, but not to that of aphids, larvae, larvae plus aphids or larvae feeding on an artificial diet. That is,
the change in searching behaviour appears in response to a volatile released by aphids when attacked. The odour released by
crushed aphids is made up entirely of aphid alarm pheromone, β-farnesene. It is likely that the adaptive significance of this
response is that it increases the ability of larvae to locate larvae that have already caught prey. By sharing the aphid kill
of another larva it is likely that a first instar ladybird larva greatly increases its probability of surviving to the next
instar. It is suggested that this social feeding is facilitated by egg clustering, which also may additionally account for
why aphidophagous ladybirds lay their eggs in clusters.
Received 28 February 2000; accepted 24 March 2000 相似文献
32.
Role of surface chemical signals in egg cannibalism and intraguild predation in ladybirds (Coleoptera: Coccinellidae) 总被引:5,自引:0,他引:5
Summary. The eggs of some ladybirds are known to be toxic to intraguild ladybird predators. However, this defence is of little value
if the eggs are killed before their toxicity becomes apparent. The results presented in this paper indicate that chemicals
on the surface of the eggs of two species of ladybirds signal the relative risk of cannibalism and intraguild predation. In
Adalia bipunctata and Coccinella septempunctata, 87% of the chemicals are alkanes. Each species of ladybird is less reluctant to eat their own eggs than those of the other
species. This asymmetry is to be expected because there is a greater risk to ladybirds from intraguild predation than cannibalism.
Similar alkanes to those on the surface of the eggs of A. bipunctata are present in tracks left by larvae and on the elytra of the adults of this species. Those in the larval tracks deter females
from ovipositing in patches of prey already being attacked by their larvae and those on the elytra are used in mate recognition.
That different context dependent messages could be signalled by similar chemicals is an example of semiochemical parsimony.
Received 25 February 2000; accepted 22 May 2000 相似文献
33.
Sarah A. Mason Jenna Dixon Faith Mambulu Andrea Rishworth Paul Mkandawire Isaac Luginaah 《Journal of Environmental Planning and Management》2015,58(8):1363-1383
The emerging challenge of managing increasing volumes of urban sewage has resulted in municipalities pursuing sustainable ways to manage urban biosolids and their by-products. Using content analysis of public debates, and situating the debate within science, policy and facility siting literature, this study examines claims and counterclaims relating to the siting of a biosolid processing facility in rural Ontario. The equivocal evidence on the health and environmental effects of biosolids resulted in a heated “expert versus lay” debate. The study critically evaluates the importance of trust and the shifting role of scientific evidence in politicised settings, while making relevant policy recommendations. 相似文献
34.
Lac Dufault sediment core trace metal distribution, bioavailability and toxicity to Hyalella azteca 总被引:2,自引:0,他引:2
Nowierski M Dixon DG Borgmann U 《Environmental pollution (Barking, Essex : 1987)》2006,139(3):532-540
To determine changes in metal distribution, bioavailability and toxicity with sediment depth, two 20-cm-long replicate cores were collected from a lake historically subjected to the influence of metal mining and smelting activity. The vertical distribution of Pb, Cd and Cu in sediment was similar for all three metals, with the surface layers showing enrichment and the deeper (pre-industrial) layers showing lower concentrations. Toxicity of each sediment core section was determined in laboratory tests with the freshwater amphipod Hyalella azteca. Bioavailable metal in each sediment slice was estimated from metal concentrations in overlying water in these toxicity tests and, for Cd, also from metal bioaccumulation. The profile for Cd in tissue was comparable to Cd in sediment and overlying water, but relative Cd bioavailability from sediment increased with sediment depth. Survival increased with increasing sediment depth, suggesting that surface sediments were probably less or non-toxic before industrialization. 相似文献
35.
In this paper we introduce a new method of analysing the relationship between nitrogen dioxide (NO2) and oxides of nitrogen (NOx) concentrations using data from the UK National Air Quality Archive. The study includes analyses of measurements from two different types of site in London, a kerbside site: Cromwell Rd, and three background sites: Bridge Place, London Bloomsbury and West London, over several years (1991–7). The data in some years showed that hourly NO2 concentrations exceeded the UK Standard of 150 ppb. Data were binned, averaged, and polynomials fitted at each site. Analysis of the resulting polynomials was used to estimate reductions in NOx emission required to achieve the National Air Quality Strategy Objective. Examination of the empirical ratio NO2:NOx (the 'yield') gives an indication of the sensitivity of the NO2 to NOx controls and the amount of NO2 that would arise from modelled values of total oxides of nitrogen. The response of NO2 to emission changes is very non-linear, implying 30–45% controls on NOx may be required. 相似文献
36.
Water quality must be considered in the development and planning aspects of water resource management. To accomplish this, the decision-maker needs to have at his disposal a systematized procedure for simulating water quality changes in both time and space. The simulation model should be capable of representing changes in several parameters of water quality as they are influenced by natural and human factors impinging on the hydrologic system. The objective of this work is two-fold. The first goal is to demonstrate the feasibility of developing and utilizing a water quality simulation model in conjunction with a hydrologic simulation model. The model represents water quality changes in both time and space in response to changing atmospheric and hydrologic conditions and time-varying waste discharges at various points in the system. This model has been developed from and verified with actual field data from a prototype system selected for this purpose. The second aim is to set forth procedural guidelines to assist in the development of water quality simulation models as tools for use in the quality-quantity management of a hydrologic unit. 相似文献
37.
R.?A.?HillEmail author L.?Barrett D.?Gaynor T.?Weingrill P.?Dixon H.?Payne S.?P.?Henzi 《Behavioral ecology and sociobiology》2003,53(5):278-286
Annual cycles in day length are an important consideration in any analysis of seasonal behaviour patterns, since they determine the period within which obligate diurnal or nocturnal animals must conduct all of their essential activities. As a consequence, seasonal variation in day length may represent an ecological constraint on behaviour, since short winter days restrict the length of the time available for foraging in diurnal species (with long summer days, and thus short nights, a potential constraint for nocturnal species). This paper examines monthly variation in activity patterns over a 4-year study of chacma baboons (Papio cynocephalus ursinus) at De Hoop Nature Reserve, South Africa. Time spent feeding, moving, grooming and resting are all significant positive functions of day length, even before chance events such as disease epidemics and climatically mediated home range shifts have been accounted for. These results provide strong support for the idea that day length acts as an ecological constraint by limiting the number of daylight hours and thus restricting the active period at certain times of year. Day length variation also has important implications across populations. Interpopulation variation in resting time, and non-foraging activity in general, is a positive function of latitude, with long summer days at temperate latitudes apparently producing an excess of time that cannot profitably be devoted to additional foraging or social activity. However, it is the short winter days that are probably of greatest importance, since diurnal animals must still fulfil their foraging requirements despite the restricted number of daylight hours and elevated thermoregulatory requirements at this time of year. Ultimately this serves to restrict the maximum ecologically tolerable group sizes of baboon populations with increasing distance from the equator. Seasonal variation in day length is thus an important ecological constraint on animal behaviour that has important implications both within and between populations, and future studies at non-equatorial latitudes must clearly be mindful of its importance. 相似文献
38.
Environmental auditing: Theory and applications 总被引:3,自引:0,他引:3
The environmental audit has become a regular part of corporate environmental management in Canada and is also gaining recognition
in the public sector. A 1991 survey of 75 private sector companies across Canada revealed that 76% (57/75) had established
environmental auditing programs. A similar survey of 19 federal, provincial, and municipal government departments revealed
that 11% (2/19) had established such programs. The information gained from environmental audits can be used to facilitate
and enhance environmental management from the single facility level to the national and international levels. This paper is
divided into two sections: section one examines environmental audits at the facility/company level and discusses environmental
audit characteristics, trends, and driving forces not commonly found in the available literature. Important conclusions are:
that wherever possible, an action plan to correct the identified problems should be an integral part of an audit, and therefore
there should be a close working relationship between auditors, managers, and employees, and that the first audits will generally
be more difficult, time consuming, and expensive than subsequent audits. Section two looks at environmental audits in the
broader context and discusses the relationship between environmental audits and three other environmental information gathering/analysis
tools: environmental impact assessments, state of the environment reports, and new systems of national accounts. The argument
is made that the information collected by environmental audits and environmental impact assessments at the facility/company
level can be used as the bases for regional and national state of the environment reports and new systems of national accounts. 相似文献
39.
Jason Bradbury Phillip Cullen Grant Dixon Michael Pemberton 《Environmental management》1995,19(2):259-272
The wash from high-speed tourist cruise launches causes erosion of the formerly stable banks of the lower Gordon River within
the Tasmanian Wilderness World Heritage Area. Speed and access restrictions on the operation of commercial cruise vessels
have considerably slowed, but not halted erosion, which continues on the now destabilized banks. To assess the effectiveness
of restrictions, bank erosion and natural revegetation are monitored at 48 sites using erosion pins, survey transects, and
vegetation quadrats. The subjectively chosen sites are grouped on the basis of geomorphology and bank materials. The mean
measured rate of erosion of estuarine banks slowed from 210 to 19 mm/year with the introduction of a 9 knot speed limit. In
areas where cruise vessels continue to operate, alluvial banks were eroded at a mean rate of 11 mm/yr during the three-year
period of the current management regime. Very similar alluvial banks no longer subject to commercial cruise boat traffic eroded
at the slower mean rate of 3 mm/yr. Sandy levee banks have retreated an estimated maximum 10 m during the last 10–15 years.
The mean rate of bank retreat slowed from 112 to 13 mm/yr with the exclusion of cruise vessels from the leveed section of
the river. Revegetation of the eroded banks is proceeding slowly; however, since the major bank colonizers are very slow growing
tree species, it is likely to be decades until revegetation can contribute substantially to bank stability. 相似文献
40.
In 1991, provisions for environmental impact assessment in New Zealand were changed significantly with the enactment of the
Resource Management Act. Among other provisions, this act requires consideration of cumulative impacts in environmental assessment
activities undertaken by planners in newly created regional authorities and district and city councils. The institutional
context in which the act is being implemented offers both opportunities and constraints to cumulative impact assessment. A
lack of methods for CIA is a recognized problem. However, methods that have been developed for environmental impact assessments
can be modified to incorporate second-, third-, and fourth-order impacts as well as to identify the direction and magnitude
of additive and synergistic impacts. Layered matrices and combined networks are examples of such methods. While they do not
allow for scientific prediction, they do provide the practitioner with the ability to consider the cumulative impacts of decisions.
This is crucial in New Zealand, where statutory requirements are ahead of established methodologies. 相似文献