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81.
Qualitative and Quantitative Assessment of Land-Use Managers' Attitudes Toward Environmental Justice
This study examines the outcome of efforts to educate federal land-use managers about their roles in implementing the Executive
Order in their respective districts. The managers participated in a 6-h Nominal Group Technique (NGT) workshop where they
were instructed to weight environmental justice issues versus others associated with hazardous waste problems in their districts.
Participant responses were quantified and analyzed through a series of rounds. After each round, participants received increasing
amounts of information on environmental justice issues.
It was hypothesized that the managers would come to a consensus that environmental justice is an important issue that should
be seriously addressed. Prior to administering the NGT, the managers appeared to have limited knowledge of environmental justice
issues and thus assigned relatively low rankings to such concerns. After being “educated” by viewing films on environmental
justice and reading related literature, in general, managers' weightings decreased and a narrower consensus developed.
The authors conclude that exposure to the issue may not be as effective as expected in convincing land-use managers to become
sensitive to justice issues so that they may effectively implement the Executive Order. 相似文献
82.
Environmental problems are often transboundary in nature. International cooperation to solve them has resulted in a growing number of environmental agreements. Supreme Audit Institutions, which are the highest national audit institutions in a country and are responsible for auditing the regularity of governmental expenditure and receipts, can contribute to the success of international cooperation by auditing government compliance with international environmental obligations and commitments. This is a new challenge for supreme audit institutions. To encourage and support this work a Workgroup on Environmental Auditing of the International Organisation of Supreme Audit Institutions has developed guidelines, which are presented in this article. The possible practical role of audit institutions is illustrated by the audit on the Convention on the Prevention of Marine Pollution by Ships, in which eight European audit institutions cooperated.
This article is published in a personal capacity and does not necessarily reflect the views of the Netherlands Court of Audit. 相似文献
83.
Two visitor-monitoring methods, video monitoring and counts by human observers, were compared in order to identify and evaluate their respective advantages and disadvantages. The analysis considered user numbers, user type (walkers, dog walkers, bicyclists, and joggers) and group size of visitors. Remarkable differences were found between the two methods for user type and use levels. At low use levels, evaluations based on video monitoring resulted in fewer single bicyclists compared to counts by human observers, whereas at high use levels, human observers counted fewer walkers and bikers than video-interpreters. Based on this comparative analysis, we derive recommendations for more effective visitor-monitoring approaches. All data were collected during a visitor-monitoring project in the Danube Floodplains National Park in Austria between 1998 and 1999. 相似文献
84.
企业是经济发展主体.国家加快推进循环经济的发展.必须落实到企业的行动中。新汶矿业集团适时提出了“煤炭产业集中化、非煤产业集优化、产业发展生态化”的新思路.创新发展模式.改变单一的产业和产品结构.围绕煤炭生产这一主导产业.积极延伸产业链.着力构建“煤、电、化(煤化工、盐化工)、建材”的新型产业格局。着眼于煤炭相关产业的全面升级.大力发展“煤基多元化”产业集群;着眼于资豫型城市的转型.全力构筑“非煤集优化”产业链条;着眼于提升矿井技术创新能力.全面提高矿区煤炭资豫综合利用水平。以四大工业园区为依托.构建特色区域经济.探索出一条煤炭企业发展循环经济的成功之路。 相似文献
85.
Janette Wenrick Boughman 《Behavioral ecology and sociobiology》1997,40(1):61-70
Individually distinctive vocalizations are ubiquitous; however, group distinctive calls have rarely been demonstrated. Under
some conditions, selection should favor calls indicating social group membership in animals that forage in groups. Greater
spear-nosed bats (Phyllostomus hastatus) give calls that appear to facilitate recognition of social group mates who are unrelated. Females give loud broadband (4–18 kHz)
vocalizations termed screech calls when departing on foraging trips and at foraging sites. Screech calls help to establish
foraging groups among social group members, and to maintain contact over the long distances they travel while foraging. I
test two hypotheses about how screech calls may be structured to convey caller identity. Individual calls may be distinct
and group members may learn to recognize each individual's calls and to associate the individual with the social group. Alternatively,
groups may give distinct calls and individuals within groups may share call characteristics. To test these hypotheses I conducted
multivariate acoustic analysis of multiple calls from 28 bats from three social groups. Although the ubiquity of individually
distinctive calls in other taxa makes this result more likely, the results reveal that group calls are highly distinctive.
Individual bats within groups are statistically indistinguishable. Calls appear to decrease slightly in frequency as bats
age. Call convergence among unrelated group mates implies vocal learning in this species.
Received: 28 March 1996 / Accepted after revision: 6 October 1996 相似文献
86.
Kate L. Palphramand Geraldine Newton-Cross Piran C. L. White 《Behavioral ecology and sociobiology》2007,61(3):401-413
Badgers are carnivores that show considerable variation in their social and spatial organization. At the westernmost part of their range, in Britain and Ireland, variation in spatial organization appears to be determined by the availability of resources. However, the majority of studies has focussed at one end of the social/spatial spectrum, where population densities are high and adjacent territories are contiguous and non-overlapping. To examine whether the same limiting factors appear to apply across a wider range of badger densities, we established a study site in a predominantly coniferous habitat within an upland area of northeast England, where population densities were predicted to be low. Seasonal home ranges of individual badgers were largest in autumn, followed by summer and spring, then winter. This pattern is reflective of the likely seasonal changes in food availability within the area, as opposed to being related to breeding patterns. There were also significant correlations between territory size and the number of grassland patches (positive) and the proportion of grassland (negative), which are consistent with predictions from the Resource Dispersion Hypothesis. Although badgers at the site were living at low to moderate densities relative to many other studied populations in Britain, they showed patterns of spatial organization that were close to those of high-density populations. The nature of the relationship between resource availability and abundance patterns is likely to have important consequences for the conservation and management of badgers and other species that show flexible spatial organization. 相似文献
87.
Martha M. Robbins Andrew M. Robbins Netzin Gerald-Steklis H. Dieter Steklis 《Behavioral ecology and sociobiology》2007,61(6):919-931
Over the past few decades, socioecological models have been developed to explain the relationships between the ecological
conditions, social systems, and reproductive success of primates. Feeding competition, predation pressures, and risk of infanticide
are predicted to influence how female reproductive success (FRS) depends upon their dominance rank, group size, and mate choices.
This paper examines how those factors affected the reproductive success of female mountain gorillas (Gorilla beringei beringei) of the Virunga Volcanoes, Rwanda from 1967–2004. Reproductive success was measured through analyses of interbirth intervals,
infant survival, and surviving infant birth rates using data from 214 infants born to 67 females. Mountain gorillas were predicted
to have “within-group scramble” feeding competition, but we found no evidence of lower FRS in larger groups, even as those
groups became two to five times larger than the population average. The gorillas are considered to have negligible “within-group
contest” competition, yet higher ranked mothers had shorter interbirth intervals. Infant survival was higher in multimale
groups, which was expected because infanticide occurs when the male dies in a one-male group. The combination of those results
led to higher surviving birth rates for higher ranking females in multimale groups. Overall, however, the socioecological
factors accounted for a relatively small portion of the variance in FRS, as expected for a species that feeds on abundant,
evenly distributed foliage. 相似文献
88.
Nestmate recognition for eggs in the honeybee (<Emphasis Type="Italic">Apis mellifera</Emphasis> L.)
Christian W. W. Pirk Peter Neumann Randall Hepburn 《Behavioral ecology and sociobiology》2007,61(11):1685-1693
Colony integrity is fundamental to social insects and is threatened by the reproduction of non-nestmates. Therefore, discrimination
between eggs derived from nestmates and non-nestmates would constitute an adaptation to prevent exploitation of the entire
cooperative group by unrelated individuals. The removal of nestmate and non-nestmate queen and worker-laid eggs was evaluated
in honeybees using colonies of Apis mellifera capensis to test female and of A. m. scutellata to test male eggs. The data show that honeybees can distinguish between nestmate and non-nestmate eggs of both sexes. Moreover,
non-nestmate female queen-laid eggs were removed significantly faster than nestmate female worker-laid eggs in A. m. capensis, indicating that nestmate recognition cues can override caste-specific ones. While the experimental manipulation accounts
for 37.2% (A. m. scutellata) or 1.6% (A. m. capensis) of variance in relation to egg removal, nestmate recognition explains 33.3% for male eggs (A. m. scutellata) and 60.6% for female eggs (A. m. capensis), which is almost twice as high as the impact of caste (16.7% A. m. scutellata; 25% A. m. capensis). Our data show a stronger effect of nestmate recognition on egg removal in the honeybee, suggesting that cues other than
caste-specific ones (viability/kin) can dominate egg removal behavior. In light of intraspecific social parasitism, preventing
the reproduction of unrelated individuals (group selection) rather than preferring queens’ eggs (kin selection) appears to
be the driving force behind the evolution of egg removal behavior in honeybees. 相似文献
89.
Rebecca J. Safran 《Behavioral ecology and sociobiology》2007,61(9):1359-1368
In most avian species, individuals are faced with two critical decisions at the start of a breeding season: choosing a breeding
site and a mate. An analysis of these decisions in light of population-level patterns, such as group size variation in social
breeders, can illuminate the causes and patterns of habitat selection behavior. Group sizes are variable in barn swallows;
however, no clear and consistent benefits of group breeding have been found in this species, and it is puzzling as to why
individuals breed socially. Previous analyses demonstrated that individuals aggregate to gain access to nests that were constructed
during previous seasons; however extra-pair matings are also prevalent in this species, raising questions about the mate-selection
strategies of females across different group sizes. In this paper, I address the question of how females make their first
site-selection decisions in terms of two features known to be causally related to seasonal reproductive success: (1) colorful
males or (2) old nests. Using experimental and observational data, I tested, but found no support for, the hypotheses that
propose female settlement decisions are a function of (1) the prevalence of colorful males or (2) the increased opportunity
for extra-pair matings at group sites. Instead, it is apparent that female settlement patterns are strongly tied to the availability
of old nests at a site. Extra-pair fertilizations are equally common across all group sizes in this population, suggesting
that females do not face a trade-off between old nests and the possibility of extra-pair mating decisions when making settlement
decisions. 相似文献
90.
《Chemosphere》1984,13(1):19-32
Pesticide and PCB analyses were completed on fat and muscle samples of 750 fish collected from 11 major lakes and rivers in Alberta. Although phenoxy and organophosphate residues were always below detectable limits, traces of chlorinated pesticides and their derivatives, particularly DDE, DDD and chlordane, were detected in most fat samples. Methoxychlor was frequently found in goldeye from the North Saskatchewan River but not recorded in fish from any other lake or river. Its presence in goldeye, a highly migratory species, was probably a result of biting-fly control programs in the Saskatchewan part of the river. PCB levels exceeded 25 mg/kg in the fat of several species from the North Saskatchewan River but were generally lower in the other systems. Analysis of 160 sediment samples from the North Saskatchewan River revealed no point source of PCB contamination, with residues always <0.01 mg/kg dry weight. 相似文献