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131.
Fractionation and Biotoxicity of Heavy Metals in Urban Dusts Collected from Hong Kong and London 总被引:13,自引:0,他引:13
Samples of urban dusts, road site dusts and car park dusts, were collected at two selected sites each in Hong Kong and London. Sequential extraction was used to characterise the chemical compositions of these urban dusts. Copper, lead, zinc, pH, electrical conductivity and organic content were measured. Biotoxicity tests of urban dusts were conducted on higher plants (Brassica chinensis and Lolium perenne), a dinoflagellate green alga (Dunaliella tertiolecta) and luminescent bacteria (Photobacterium phosphoreum). A significant correlation was found between total lead (r =; – 0.70, p < 0.01) and zinc (r =; – 0.74, p < 0.05), and the 20 min – EC50 using P. phosphoreum. In addition, there was a significant correlation (r = – 0.72, p < 0.01) between the exchangeable lead content in dust and the 48 h- EC30 using D. tertiolecta. No specific trend was obtained for higher plants. Total lead and zinc contents were higher in dusts from London while the percentage of exchangeable fraction of metal contents was higher in those from Hong Kong. 相似文献
132.
133.
Oded Berger‐Tal Daniel T. Blumstein Scott Carroll Robert N. Fisher Sarah L. Mesnick Megan A. Owen David Saltz Colleen Cassady St. Claire Ronald R. Swaisgood 《Conservation biology》2016,30(4):744-753
The role of behavioral ecology in improving wildlife conservation and management has been the subject of much recent debate. We sought to answer 2 foundational questions about the current use of behavioral knowledge in conservation: To what extent is behavioral knowledge used in wildlife conservation and management, and how does the use of animal behavior differ among conservation fields in both frequency and types of use? We searched the literature for intersections between key fields of animal behavior and conservation and created a systematic heat map (i.e., graphical representation of data where values are represented as colors) to visualize relative efforts. Some behaviors, such as dispersal and foraging, were commonly considered (mean [SE] of 1147.38 [353.11] and 439.44 [108.85] papers per cell, respectively). In contrast, other behaviors, such as learning, social, and antipredatory behaviors were rarely considered (mean [SE] of 33.88 [7.62], 44.81 [10.65], and 22.69 [6.37] papers per cell, respectively). In many cases, awareness of the importance of behavior did not translate into applicable management tools. Our results challenge previous suggestions that there is little association between the fields of behavioral ecology and conservation and reveals tremendous variation in the use of different behaviors in conservation. We recommend that researchers focus on examining underutilized intersections of behavior and conservation themes for which preliminary work shows a potential for improving conservation and management, translating behavioral theory into applicable and testable predictions, and creating systematic reviews to summarize the behavioral evidence within the behavior‐conservation intersections for which many studies exist. 相似文献
134.
Diana O. Fisher Susan Nuske Sally Green Jennifer M. Seddon Brenda McDonald 《Behavioral ecology and sociobiology》2011,65(4):593-605
One of the few mammal species reported to have a mating system of lek promiscuity is the tree-hollow nesting marsupial, the
agile antechinus, Antechinus agilis. Past conclusions about its mating system have been based on seasonal changes in social group size, sex-specific nest switching
and space use. Thermoregulation has also been suggested as an explanation for variation in social behaviour in this species
and its relatives. We tested predictions of the lekking and thermoregulation hypotheses to explain sociality in cavity nesting
antechinuses using published data, and new data on brown and subtropical antechinuses. We found that across four species,
social group size is negatively correlated with daily minimum temperature, but not with timing of breeding. Females have a
matrilineal fission–fusion social system, which continues during the brief mating season, and males range increasingly further
throughout their lives, contacting as many females as possible in nests. Males show no indication of fission–fusion sociality.
All evidence in species other than A. agilis, and some data on A. agilis, indicate a mating system of scramble polygyny, and not lek promiscuity. We conclude that across species, thermoregulation
is the main reason for seasonal variation in nesting group size in both sexes. 相似文献
135.
Bert Hölldobler Malu Obermayer Nicola J. R. Plowes Brian L. Fisher 《Die Naturwissenschaften》2014,101(7):527-532
Fisher and Robertson (Insect Soc 46: 78–83, 1999) discovered the production of silk-like secretions emerging from slit-shaped openings along the anterior margin of the ventral hypostoma of Melissotarsus ant workers. The current histological study describes a hitherto unknown hypostomal gland from which this silk-like substance originates. In addition, this study describes a new basitarsal gland in the three pairs of legs of Melissotarsus workers. 相似文献
136.
Alanna?DurkinEmail author Charles?R.?Fisher Erik?E.?Cordes 《Die Naturwissenschaften》2017,104(7-8):63
The deep sea is home to many species that have longer life spans than their shallow-water counterparts. This trend is primarily related to the decline in metabolic rates with temperature as depth increases. However, at bathyal depths, the cold-seep vestimentiferan tubeworm species Lamellibrachia luymesi and Seepiophila jonesi reach extremely old ages beyond what is predicted by the simple scaling of life span with body size and temperature. Here, we use individual-based models based on in situ growth rates to show that another species of cold-seep tubeworm found in the Gulf of Mexico, Escarpia laminata, also has an extraordinarily long life span, regularly achieving ages of 100–200 years with some individuals older than 300 years. The distribution of results from individual simulations as well as whole population simulations involving mortality and recruitment rates support these age estimates. The low 0.67% mortality rate measurements from collected populations of E. laminata are similar to mortality rates in L. luymesi and S. jonesi and play a role in evolution of the long life span of cold-seep tubeworms. These results support longevity theory, which states that in the absence of extrinsic mortality threats, natural selection will select for individuals that senesce slower and reproduce continually into their old age. 相似文献
137.
Spatial Patterns in the Abundance of the Coastal Horned Lizard 总被引:7,自引:0,他引:7
138.
139.
The Decline of Amphibians in California's Great Central Valley 总被引:4,自引:0,他引:4
Declines in amphibian populations are rarely reported on the community or ecosystem level. We combined broad-scale field sampling with historical analyses of museum records to quantify amphibian declines in California's Great Central Valley. Overall, amphibians showed an unambiguous pattern of decline, although the intensity of decline varied both geographically and taxonomically. The greatest geographical decline was detected in the counties of the Sacramento and San Joaquin Valleys. Two species, Rana aurora and Bufo boreas were identified as the most affected by decline, whereas Pseudacris regilla was the least affected. The Coast Range counties had little or no detectable decline. We provide new evidence implicating introduced predators as a primary threat. Introduced predators occur at lower elevations than native species, and our data indicate that for some native species there has been significant restriction to higher elevation sites from a formerly broader distribution. Our historical approach provides a strategy for identifying declining amphibian communities that complements more detailed, long-term monitoring programs and provides an assessment of the pattern of change that is a necessary prerequisite for the development of field experiments that test hypothesized mechanisms of change. 相似文献
140.
This study identified correlates of attitude toward an impending employer-initiated relocation, then followed up by predicting post-transfer attitude and adjustment difficulty in the same sample. Predictors suggested by past research on mobility attitudes (i.e. demographic characteristics and attributes of the pre-move location) were less important in explaining pre-move attitude toward the transfer than were expected attributes of the new location. After the move, experienced aspects of the new location such as role ambiguity, degree of advancement, and community and job satisfaction were the strongest predictors of overall post-move attitude and adjustment difficulty. In many cases, pre-move expectations about attributes of the new location were not related to affect or adjustment after the move, suggesting that pre-move expectations may have been inaccurate. Implications for theory, research, and organizational practice are discussed. 相似文献