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Well-developed antennae are crucial for many insects, but especially for scramble competitors, who race to find their mates using female sex cues. In these systems, the ability of males to locate females quickly is thought to be under strong selection. A rarely tested assumption is that males with more sensory structures are able to locate females faster. In the present study, we used the false garden mantid Pseudomantis albofimbriata to investigate male antennal morphology and its effect on male efficiency in finding a mate. We used scanning electron microscopy to describe the major sensilla types and their arrangement along the length of male antennae. We also conducted field enclosure trials relating male antennal morphology to scramble competition in this system. We identified six different types of antennal sensilla (cheatic, trichoid, basiconic, grooved peg, ceolocapitular and campaniform) on male P. albofimbriata antennae. As expected, males who had more trichoid sensilla located females quicker than did males with fewer sensilla. Results of the current study suggest that antenna morphology plays a significant role in mate location and hence scramble competition in the P. albofimbriata mating system. 相似文献
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Katherine?P.?Gill Ellen?van?Wilgenburg Peter?Taylor Mark?A.?ElgarEmail author 《Die Naturwissenschaften》2012,99(3):245-248
Social insect colonies exhibit highly coordinated responses to ecological challenges by acquiring information that is disseminated
throughout the colony. Some responses are coordinated directly from the signals produced by individuals that acquired the
information. Other responses may require information to be transferred indirectly through a third party, thereby requiring
colony-wide retention of information. Social insects use colony signature odours to distinguish between nestmates and non-nestmates,
and the level of aggression between non-nestmates typically varies according to the distance between colonies and thus their
history of interactions. Such coordinated, colony-specific responses may require information about particular odours to be
disseminated and retained across the colony. Our field experiments with weaver ants reveal colony-wide, indirect acquisition
and retention of the signature odours of a different colony with which they had experienced aggression. These data highlight
the significance of interaction history and suggest the presence of a collective memory. 相似文献
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Edward J. Brooks David W. Sims Andy J. Danylchuk Katherine A. Sloman 《Marine Biology》2013,160(10):2535-2546
The Caribbean reef shark (Carcharhinus perezi), an abundant coral-reef-associated apex predator, is one of the most economically and ecologically important, yet least studied species of large shark in the greater Caribbean region. The relative abundance and population structure of C. perezi off Cape Eleuthera, The Bahamas, was surveyed by standardised longline surveys from May 2008 to October 2011, which resulted in the capture of 331 sharks. Abundance peaked in the summer and was lowest during the winter. Females were 1.6 times more abundant than males and the assemblage was dominated by immature female sharks (45.5 %). The abundance of mature male and female sharks peaked a month apart in June and August, respectively. All 331 sharks were tagged and released with 15.4 % being recaptured after periods at liberty between 5 and 1,159 days (Mean = 333.4 ± 42.7 SE). The mean distance between tagging and recapture was 1.77 km for recaptures in excess of 6 months, indicating seasonally stratified philopatry in this species. C. perezi inhabiting Bahamian waters have developed complex habitat use patterns that are both spatiotemporally and demographically segregated, most probably in response to the large and diverse habitat mosaic available on the Bahamas Banks compared to contemporary study sites. This study represents an important step in understanding the spatiotemporal population structure of C. perezi and illustrates the potential for studies examining behavioural plasticity in response to environmental variation and anthropogenic disturbance. 相似文献
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Robert G. Haight Katherine Ralls † and Anthony M. Starfield‡ 《Conservation biology》2000,14(5):1298-1307
Abstract: When translocating individuals to found new populations, managers must allocate limited funds among release and monitoring activities that differ in method, cost, and probable result. In addition, managers are increasingly expected to justify the funding decisions they have made. Within the framework of decision analysis, we used robust optimization to formulate and solve different translocation problems in which both population growth and future funding were uncertain. Performance criteria included maximizing mean population size and minimizing the risk of undesirable population-size outcomes. Robust optimization provided several insights into the design of translocation strategies: (1) risk reduction is obtained at the expense of mean population size; (2) as survival of released animals becomes more important, funds should be allocated to release methods with lower risks of failure, regardless of costs; (3) the performance gain from monitoring drops as the proportion of a fixed budget required to pay for monitoring increases; and (4) as the likelihood of obtaining future funding increases, more of the existing budget should be spent on building release capacity rather than saved for future operating costs. These relationships highlight the importance of performance criteria and economic costs in determining optimal release and monitoring strategies. 相似文献
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