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981.
John?A.?VucetichEmail author Leah?M.?Vucetich Rolf?O.?Peterson 《Behavioral ecology and sociobiology》2012,66(2):295-303
For a wide range of taxa, partial prey consumption (PPC) is a frequent occurrence. PPC may arise from physiological constraints
to gut capacity or digestive rate. Alternatively, PPC may represent an optimal foraging strategy. Assessments that clearly
distinguish between these causes are rare and have been conducted only for invertebrate species that are ambush predators
with extra-intestinal digestion (e.g., wolf spiders). We present the first strong test for the cause of PPC in a cursorial
vertebrate predator with intestinal digestion: wolves (Canis lupus) feeding on moose (Alces alces). Previous theoretical assessments indicate that if PPC represents an optimal foraging strategy and is not caused by physiological
limitations, then mean carcass utilization is negatively correlated with mean kill rate and the utilization of individual
carcasses is uncorrelated with time between kills. Wolves exhibit exactly this pattern. We explore how the typical portrayal
of PPC by wolves has been not only misleading but also detrimental to conservation by promoting negative attitudes toward
wolves. 相似文献
982.
László?Zsolt?GaramszegiEmail author Anders?Pape?M?ller 《Behavioral ecology and sociobiology》2012,66(1):107-119
Hamilton and Zuk (Science 218:384–387, 1982) supported their influential hypothesis of parasite-mediated sexual selection based on a positive interspecific correlation
between the prevalence of blood parasites and the expression of male displays in birds. However, subsequent studies provided
mixed support for this relationship after considering several confounding factors. Here, we revisit this fundamental prediction
by refining the analyses through implementation of recent methodological advancements. First, we distinguish between prevalence
data obtained through microscopic and molecular tools, as PCR-based detection methods may be more sensitive for detecting
infection. Second, we use quantitative estimates of both acoustic and visual signals of males, in which color measurements
adopt the perspective of avian vision. Third, applying modern phylogenetic comparative approaches, we correct for phylogenetic
inertia as well as heterogeneity in sampling effort. Fourth, we distinguish between prevalence transition states, as we compare
species with and without evidence of infection and also monitor changes in parasite prevalence only in species in which blood
parasites are detected. We show that given the considerable variation among populations, the repeatability of prevalence at
the within-species level is modest. We failed to detect a strong interspecific relationship between the prevalence of blood
parasites and sexual traits. However, we found that an evolutionary increase from zero to non-zero prevalence is likely to
be accompanied by an increase in trait expression in males, but further increase from non-zero prevalence to a higher level
of infection tends to be associated with a reduced degree of trait elaboration. Our results provide some support to the Hamilton
and Zuk hypothesis, but the relationship between blood parasites and male displays varies among traits depending on degree
of infection. 相似文献
983.
Thomas?KlefothEmail author Christian?Skov Jens?Krause Robert?Arlinghaus 《Behavioral ecology and sociobiology》2012,66(4):547-559
To showcase the importance of genotype × environment interactions and the presence of predation risk in the experimental assessment
of boldness in fish, we investigated boldness in terms of feeding behavior and refuge use in two genetically different populations
of juvenile carp (Cyprinus carpio) in two replicated experimental conditions in ponds and laboratory tanks. The populations were expected to exhibit genetic
differences in boldness due to differential evolutionary adaptation to low-predation-risk pond aquaculture conditions. Boldness
was measured in variants of open-field trials with and without implementation of additional predation risk-stimuli by angling
on feeding spots. Without explicit implementation of risk, genotypes adapted to low-risk environments, i.e., domesticated
mirror carp behaved consistently bolder than their less domesticated scaled conspecifics in the pond environment, but not
in the laboratory environment. When we implemented artificial risk-stimuli by angling on previously safe feeding spots, boldness
differences among genotypes also emerged in the laboratory environment, indicating strong genotype × environment effects on
boldness behavior of carp. The expected genetic basis of boldness differences among genotypes was clearly supported in the
pond environment, while the laboratory study revealed these patterns only under inclusion of explicit risk-stimuli. Our study
thus underscores that boldness may involve both a basal component that is expressed independently of obvious predation risk
(e.g., in open fields) and a component revealed in relation to explicit predation risk, and both dimensions may respond differently
in behavioral tests. 相似文献
984.
Hydrochemical, multivariate statistical, and inverse geochemical modeling techniques were used to investigate the hydrochemical
evolution within the Ain Azel aquifer, Algeria. Cluster analysis based on major ion contents defined 3 main chemical water
types, reflecting different hydrochemical processes. The first group water, group 1, has low salinity (mean EC = 735 μS/cm).
The second group waters are classified as Cl–HCO3-alkaline earth type. The third group is made up of water samples, the cation composition of which is dominated by Ca and
Mg with anion composition varying from dominantly Cl to dominantly HCO3 plus SO4. The varifactors obtained from R-mode FA indicate that the parameters responsible for groundwater quality variations are
mainly related to the presence and dissolution of some carbonate, silicate, and evaporite minerals in the aquifer. Inverse
geochemical modeling along groundwater flow paths indicates the dominant processes are the consumption of CO2, the dissolution of dolomite, gypsum, and halite, along with the precipitation of calcite, Ca-montmorillonite, illite, kaolinite,
and quartz. 相似文献
985.
Patinha C Reis AP Dias C Cachada A Adão R Martins H Ferreira da Silva E Sousa AJ 《Environmental geochemistry and health》2012,34(2):213-227
Previous environmental biomonitoring studies indicated higher environmental lead (Pb) pollution levels at the districts of
Aveiro and Leiria (Portugal). In evaluating the risk for human health, which is associated with contaminated soils after oral
uptake, total soil concentrations have generally been held against criteria established from toxicological studies based upon
the assumption that the uptake of the contaminant is similar in the toxicological studies and from the soils assessed. This
assumption is not always valid, as most toxicological studies are carried out with soluble forms of the contaminants, whereas
many soil contaminants are or become embedded in the soil matrix and thus exhibit limited availability. This study intends
to estimate the soluble fraction of Pb in the soils from central Portugal, and to assess the bioaccessibility of Pb and, hence,
infer exposure and risk for human health. Yet, as the physical–chemical properties of the soil exert some control over the
solubility of Pb in the surface environment, the relation between such soil properties and the estimated soluble and/or bioaccessible
fractions of Pb is also investigated. Other objective, with a more practical nature, was to give some contribution to find
a suitable in vitro mimetic of the gastrointestinal tract environment. The results indicate relatively low total metal concentrations
in the soils, even if differences between regions were observed. The Aveiro district has the higher total Pb concentration
and the metal is in more soluble forms, that is, geoavailable. Soils with higher concentrations of soluble Pb show higher
estimates of bioaccessible Pb. Soil pH seems to influence human bioaccessibility of Pb. 相似文献
986.
John?M.?Townsend-MehlerEmail author Fred?C.?Dyer 《Behavioral ecology and sociobiology》2012,66(2):275-286
While there has been considerable research on the behavioral processes that underlie animals’ ability respond to shifting
rewards, it remains unclear how animals coordinate multiple processes over time. To investigate this, we compared the behavior
of honeybees (Apis mellifera) and bumblebees (Bombus impatiens), in an open-ended search task. Bees were given brief access to a high-quality food source, which then became non-rewarding.
Then, over an extended period, we examined (1) bees’ tendency to persist at the depleted site, (2) their tendency to return
to a different low-quality food source where they had been foraging previously, (3) their tendency to return to the hive,
and (4) how previous reward history influenced their tendency to shift among these options. Compared to bumblebees, honeybees
were much slower to abandon the depleted site and were much more likely to make trips to the hive while bumblebees were much
more likely to return to the familiar low-quality site. These observed species differences are interpreted in terms of evolved
individual and social differences between these species. We show evidence of well-studied behavioral processes such as extinction,
negative contrast effects, and reliance on a social group, and provide, for the first time, a picture of how these processes
interact with one another as part of a common sequential decision-making process. 相似文献
987.
Matteo?Pizzolon Lisa?Locatello Robert?R.?Warner Nicole?Chimento Livio?Finos Maria?B.?RasottoEmail author 《Behavioral ecology and sociobiology》2012,66(3):497-504
Recent theoretical models predict that the relative allocation to advertisement and parental care depends on whether paternal
care is necessary for offspring survival: In species with exclusive male care, male investment in attraction is expected to
reliably indicate paternal care effort and male phenotypic quality. Previous research, yielding contrasting results, has considered
how one trait involved in mate attraction interacts with parental care or a specific aspect of male quality. In the blenny
Salaria pavo, we perform a comprehensive analysis of the interplay between overall male attractiveness and male quality, the latter in
terms of fertility, condition, and parental care. In this fish, males are larger than females, exhibit two sexually dimorphic
traits (head crest and anal glands), and solely care for eggs. We generated a male attractiveness index through principal
component analyses of morphological traits and quantified parental effort as the total time spent in egg care. In addition,
we analyzed the relationships between specific components of attractiveness and male qualities. In agreement with theory predictions,
we found that male overall attractiveness is a reliable indicator of fertility, in terms of sperm number, but is unrelated
to body condition and parental care effort, with males able to perform high levels of care regardless of their level of advertisement.
However, the relative expression of head crest area appears positively related to sperm number but is traded-off with parental
care effort. These findings underline the need, in addressing real patterns, to consider interactions between multiple aspects
of male display and quality. 相似文献
988.
An animal’s use of space may be strongly influenced by habitat edges and neighboring conspecifics encountered in and around
its home range. Habitat edges are known to affect species density and distribution, but their impact on home range use is
largely unknown. Additionally, among large animals, interactions with neighbors become particularly important as increasing
home range size leads to decreasing exclusivity of resource use, but the effect of neighbors on home range use remains poorly
understood. Here, we examine the influence of neighbors and habitat edges on the ranging patterns of three groups of Phayre’s
leaf monkeys (Trachypithecus phayrei crepusculus) in northeast Thailand over a period of more than 2 years. The study animals occupied dry evergreen forest, and adjacent
patches of dry dipterocarp forest created a habitat edge and formed barriers between some groups. We found that the use of
home range interiors was 50–90% higher than the border areas, indicating concentrated use of resources within the home range.
The use of peripheral areas was influenced by social organization, the presence of neighboring groups, and forest edges. While
one multimale group showed no particular habitat preference, two single-male groups preferred areas bordering dry dipterocarp
habitat and avoided areas bordering neighboring groups, suggesting that the threat of neighbors mediated border presence.
Additionally, groups may have been attracted to the forest edge, where conspecific competitors are absent and increased sunlight
may increase resource abundance and/or quality. This study revealed that the use of border areas can be modulated by neighboring
groups and habitat edges, thereby adding to our understanding of home range use among territorial species in heterogeneous
habitats. 相似文献
989.
Ivonne?MeucheEmail author K.?Eduard?Linsenmair Heike?Pr?hl 《Behavioral ecology and sociobiology》2012,66(4):613-621
In many species male reproductive success is limited by access to females. Territoriality is one behavioural strategy which
helps to acquire females. In the present study, we investigated the correlation between territory size and (1) female availability
and (2) rate of intrusion by conspecific males in strawberry poison frogs, Oophaga pumilio. Males defended smaller territories in areas with a high female density and high rate of intrusion by conspecific males.
Only males with high body condition values were able to establish territories in areas of high female density probably due
to better fighting abilities. Moreover, dominant calling frequency was lower during agonistic interactions. Because only males
with high body condition values were able to produce very low dominant frequencies, the acoustic properties appear to be an
honest signal containing information about fighting abilities. Thus, the negative correlation between dominant frequency and
mating success of males found in previous studies seems to be in part the result of intrasexual competition between males. 相似文献
990.
Meeghan?E.?GrayEmail author Elissa?Z.?Cameron Mary?M.?Peacock David?S.?Thain Veronica?S.?Kirchoff 《Behavioral ecology and sociobiology》2012,66(4):529-537
A growing number of studies conducted on diverse taxa have shown that extra-pair/group paternity is higher than what would
be predicted from behavioral observations alone. While it may be beneficial for females to mate with multiple males, this
often results in offspring not sired by the behavioral father, which could influence offspring survival, especially in social
mammals. Feral horses (Equus caballus) maintain stable social relationships over several years, usually with one stallion defending a harem band of unrelated mares
against other males. Sneak copulations by subordinate males have been observed and mares sometimes change bands, both of which
can result in foals sired by males other than the dominant band stallion. We measured female fidelity in free-ranging feral
horses in 23 bands, with 51 foals over four foaling seasons and tested offspring paternity against parental behaviors. We
used 12 polymorphic microsatellite loci and the program CERVUS 2.0 to determine and exclude potential sires. The majority
of mares remained in the band with the sire of their foal resulting in most foals being sired by the band stallion. Most foals
that were not sired by the band stallion were born in the year after a round-up and we could not determine if they were the
result of band changing or sneak copulations. Foals born into a band without their sire had lower survival rates and mothers
were significantly more protective of foals not sired by the band stallion. These findings suggest that band stability increases
the reproductive success of mares and support the importance of infanticide risk in equid social structure. 相似文献