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31.
Honey bee foragers as sensory units of their colonies 总被引:5,自引:0,他引:5
Thomas D. Seeley 《Behavioral ecology and sociobiology》1994,34(1):51-62
Forager honey bees function not only as gatherers of food for their colonies, but also as sensory units shaped by natural selection to gather information regarding the location and profitability of forage sites. They transmit this information to colony members by means of waggle dances. To investigate the way bees transduce the stimulus of nectar-source profitability into the response of number of waggle runs, I performed experiments in which bees were stimulated with a sucrose solution feeder of known profitability and their dance responses were videorecorded. The results suggest that several attributes of this transduction process are adaptations to enhance a bee's effectiveness in reporting on a forage site. (1) Bees register the profitability of a nectar source not by sensing the energy gain per foraging trip or the rate of energy gain per trip, but evidently by sensing the energetic efficiency of their foraging. Perhaps this criterion of nectar-source profitability has been favored by natural selection because the foraging gains of honey bees are typically limited by energy expenditure rather than time availability. (2) There is a linear relationship between the stimulus of energetic efficiency of foraging and the response of number of waggle runs per dance. Such a simple stimulus-response function appears adequate because the range of suprathreshold stimuli (max/min ratio of about 10) is far smaller than the range of responses (max/min ratio of about 100). Although all bees show a linear stimulus-response function, there are large differences among individuals in both the response threshold and the slope of the stimulus-response function. This variation gives the colony a broader dynamic range in responding to food sources than if all bees had identical thresholds of dance response. (3) There is little or no adaptation in the dance response to a strong stimulus (tonic response). Thus each dancing bee reports on the current level of profitability of her forage site rather than the changes in its profitability. This seems appropriate since presumably it is the current profitability of a forage site, not the change in its profitability, which determines a site's attractiveness to other bees. (4) The level of forage-site quality that is the threshold for dancing is tuned by the bees in relation to forage availability. Bees operate with a lower dance threshold when forage is sparse than when it is abundant. Thus a colony utilizes input about a wide range of forage sites when food is scarce, but filters out input about low-reward sites when food is plentiful. (5) A dancing bee does not present her information in one spot within the hive but instead distributes it over much of the dance floor. Consequently, the dances for different forage sites are mixed together on the dance floor. This helps each bee following the dances to take a random sample of the dance information, which is appropriate for the foraging strategy of a honey bee colony since it is evidently designed to allocate foragers among forage sites in proportion to their profitability. 相似文献
32.
Bert?H?lldoblerEmail author E.?David Morgan Neil?J.?Oldham Jürgen?Liebig Yue? Liu 《Chemoecology》2004,14(2):101-106
Summary. Dufour gland secretions of the harvester ants
Pogonomyrmex barbatus, P. rugosus
and P. maricopa were
investigated. The glandular blends exhibit species specific
patterns, but more importantly, based on indiviual profiles of
Dufour gland contents of colony members it is possible to
separate the colonies from each other in each species. It is
possible that these collective colony specific cues serve as
longer lasting trunk route markers. Behavioral tests demonstrate
that workers of P. rugosus
prefer homing routes marked by members of their own colony to routes marked
by a foreign conspecific colony. 相似文献
33.
Lynn E. Fletcher 《Behavioral ecology and sociobiology》2007,61(12):1809-1821
Group living confers both benefits and costs to the individuals involved. Benefits may include enhanced defense, thermoregulation,
and increased foraging efficiency while costs often involve competition for resources such as food, shelter, and mates. Communication
provides a medium of exchange among individuals engaged in either cooperative or competitive interactions. The functional
analysis of signals within groups therefore requires testing both cooperative and competitive functions, although the latter
is infrequently done. In this paper, I study the use of two vibrational signals in a gregarious, processionary Australian
sawfly larva, Perga affinis: tapping and contractions. Tapping involves striking the substrate with the sclerotized portion of the abdominal tail and
a contraction is a fast, whole-body twitch, which is both tactile and vibrational in its transmission. For tapping, I first
demonstrate that it is a form of communication, as tapping of one larva elicits tapping in another, and that it is transmitted
through substrate vibrations. I then test whether the signal is mostly cooperative or competitive in nature by examining it
in light of two hypotheses: (1) the Group Coordination hypothesis, stating that the signal functions to maintain group cohesiveness
and (2) the Competitive Signaling hypothesis, stating that tapping serves as a competitive assessment signal between larvae
while feeding. For contractions, I test only the group coordination hypothesis that they serve to coordinate and initiate
group movement. Results support the group coordination hypothesis for each signal. While feeding, lone larvae (without potential
competitors) were significantly more likely to tap than those in groups, and this trend continued in non-feeding situations.
Contractions regularly preceded periods of group movement during processions and were given with increasing frequency before
departure from preforaging clusters. The vibrational signals in this processionary species likely function cooperatively to
maintain group cohesiveness and coordinate movement. 相似文献
34.
Kevin J. Delaney J. Andrew Roberts George W. Uetz 《Behavioral ecology and sociobiology》2007,62(1):67-75
Male signaling behaviors are often studied in a single context but may serve multiple functions (e.g., in male–male competition
and female mate choice). We examined the issue of dual function male signals in a wolf spider species Schizocosa ocreata (Hentz) that displays the same species-specific signaling behaviors in both male–male and male–female contexts. These signaling
behaviors have been described as either aggression or courtship according to the context observed. We tested the possibility
of dual functions by comparing the relationship between behaviors and outcome of male–male contests (winner/loser) and male–female
mating encounters (mating success). Frequency, rate, and mean duration of signaling behaviors did not vary with outcome of
male–male contests, which appears instead to be based upon relative size and body mass. Winners of contests had significantly
greater body mass than losers, and greater mass relative to opponents was significantly associated with probability of winning.
Overall, signaling rates were much higher in male–female interactions than in male–male contests and were higher for males
that successfully mated than for those that did not mate. Mean duration of some male displays was also greater for males that
successfully mated. However, male size was not associated with probability of mating. Taken together, results suggest an intersexual
selection context for the current function of male signals in these wolf spiders and that increased display vigor is associated
with male mating success. 相似文献
35.
36.
Carbon Capture and Storage (CCS) is a promising technology for reducing carbon emissions, but the public is often reluctant to support it. To understand why public support is lacking, it is crucial to establish what citizens think about the arguments that are used by proponents and opponents of CCS. We determined the persuasiveness, importance and novelty of 32 arguments for and against CCS using a discrete choice experiment in which respondents made consecutive choices between pairs of pro or con arguments. We used latent class models to identify population segments with different preferences. The results show that citizens find arguments about climate protection, which is the primary goal of CCS, less persuasive than other arguments, such as normative arguments (for example ‘a waste product such as CO2 should be disposed of properly’) or arguments about benefits of CCS for energy production and economic growth. This discrepancy complicates communication that aims to convince citizens of the benefits of CCS for climate protection. 相似文献
37.
Dale E. Heydlauff 《Environmental management》1996,20(6):963-966
The quality and sustainability of the natural environment is a matter of inestimable value and is critical to public health and welfare. All species have a purpose, and they exist for the betterment of other species. It is, therefore, incumbent on all humans to do their part in the preservation of this vast, diverse ecosystem called Earth. All humans are the beneficiaries, the ultimate customers, of a sound environment—water that is safe to drink, air that can be breathed, and soil that will sustain crops. There must be a commitment to leaving a clean and healthy planet for generations to follow, an earth which is enhanced, not diminished, by humans' presence. 相似文献
38.
The separate collection of waste, and especially of recyclables with specific collection systems, would not be possible without
the involvement of the users. Apart from the physical installations such as collection containers, collection points, etc.,
the motivation of the users is an essential component. Motivation can be reinforced through public relations work. In addition
to the underlying technical considerations, this paper describes the difference between communication in general and public
relations and specifically examines public involvement in recycling. Through the use of examples, we look at the targeted
users and typical media employed. Furthermore, we analyzes the development of public involvement. The examples show that public
relations for recycling strategies relies to a great extent on attitudes, habits, and access to the target group. Thus, standardized
procedures cannot be developed. For these reasons, public relation activities must be planned carefully and professionally
and include an analysis of the target group, choice of media, and verification of success. 相似文献
39.
Fire regimes are needed for healthy forest ecosystems, but citizens who live parallel to public forests do not always understand or favour the mechanisms land managers use for fire prevention and preparation. One way that land managers and citizens may share concerns and overcome barriers is through effective communication, allowing both parties to adequately prepare for a wildfire event. While collaboration between land managers and citizens has been well studied, the research on communication between citizens and among land managers is less prevalent yet equally important. The lack of research on communication between these parties creates an incomplete picture of the spectrum of communication that takes place in preparation for a wildland fire event. This paper reviews the current literature on communication between and among citizens and land managers before a wildfire event. 相似文献
40.
Introduction: Injuries and work-related musculoskeletal disorders (MSDs) are common among masons. SAfety Voice for Ergonomics (SAVE) integrates training in ergonomic and safety problem-solving skills into masonry apprenticeship training. The purpose of this study was to assess the efficacy of text messaging to reinforce SAVE program content. Method: SAVE effectiveness was evaluated at masonry apprenticeship training centers across the United States by comparing three experimental groups: (1) Ergonomics training, (2) Ergonomics and Safety Voice training, and a (3) Control. Apprentices received SAVE training with their standard instruction. To reinforce classroom training, refresher training was implemented by sending weekly text messages for six months. Half of the text messages required a response, which tested knowledge or assessed behavior, while the remaining reiterated knowledge. Apprentices (n = 119) received SAVE text messages. Response rates and percentage of correct responses were compared with chi-square tests and independent group t-tests. Multivariable logistic regression analysis predicted apprentice response with selected demographic and work experience variables. Finally, feedback on of the use of text messaging was obtained. Result: Of 119 participants, 61% (n = 72) responded to at least one text message. Logistic regression revealed that being a high school graduate and a brick and block mason significantly affected the odds of responding. Sixty-nine percent of apprentices agreed that text messages reinforced SAVE content. Conclusion: Even though there was no training center requirement to respond, the high response rate suggests that text messaging can effectively be used to reinforce ergonomics and safety voice training for both knowledge and behavior. Practical Application: The prevalent use of text messaging creates opportunities to reinforce health and safety training and engage workers, especially for populations that may be at various locations over time such as construction sites. Instructors and practitioners should consider the utility of text messaging for supporting their training and safety programs. 相似文献