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The Gitksan and Wet’suwet’en of Northwestern British Columbia formerly used landscape burning to manage patches of black huckleberry
(Vaccinium membranaceum), the most important plant resource of their seasonal round. In view of its significance one might postulate that managed
sites would conform to a biophysical or ecological type to maximize return for effort. However, a survey of a number of traditionally
managed sites indicated that managed sites are characterized by wide variation in biophysical attributes including elevation,
aspect and moisture regime, while proximity to fishing sites, village sites, or sites for harvest of alpine resources proved
to be a common factor in known historic berry patch sites. We conclude that characterization of the ideal site type for aboriginal
V. membranaceum management must include the economy and social institutions of the local First Nations and requires an enhanced appreciation
for the sophistication of the strategies and techniques employed in their management and utilization of the species.
相似文献
Leslie Main Johnson (Corresponding author)Email: |
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Barbara York Main 《Journal of Insect Conservation》2001,5(1):9-25
In response to geohistorical events from the Mesozoic through the Tertiary with contraction of mesic forest to southwestern and eastern montane and coastal regions, and expansion of woodlands and xeric shrublands, nobreak Australian spiders today comprise relict families and genera (confined to Gondwanan habitats and refuges) along with later evolved representatives which have adapted to changing environments. Tropical relicts also persist in refugia in the arid interior while some spiders (both mygalomorphs and araneomorphs) have adapted to arid conditions, mainly through specialized behaviours. Although fire has become increasingly a phenomenon of the Australian environment it is doubtful whether any spiders are adapted to fire per se. European settlement has impacted differentially on relictual and later evolved representatives; a few species, including the funnelweb (Atrax
robustus) and redback spider (Latrodectus hasselti) have benefited through enhanced habitat opportunities and some species of Badumna and other genera have become synanthropic. It is suggested that conservation strategies need to consider the ecoevolutionary history of particular spiders and their natural vulnerability or resilience to environmental factors. 相似文献
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Rolland J. Main 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1928,7(4):611-616
Summary In the case of viviparous perch and goldfish, unilateral blinding causes a tilting on the anterior-posterior axis towards the normal eye, the amount of tilting being dependent upon the intensity of light. With a sudden change to a greater intensity of light, the fish circle toward the blind eye, and upon sudden reduction of the intensity they often circle toward the normal eye. The similarity of this reaction to the effect of unilateral blinding of insects is offered as an explanation.It is suggested that these results explain the experiments of Pearcy and Koppanyi. These workers dislocated one eye of a goldfish and removed the other one, explaining the consequent tilting of the fish as due to an attempt of the animal to regain its normal visual field. Since the fish was now totally blind, due to the effect of the operation, no tilting was present. As the dislocated eye. gradually recovered its vision, the fish began to tilt, reaching maximal tilting several weeks afterwards. However, since I have produced tilting by unilateral blinding alone, it seems evident that the results obtained by those two experimenters were also due to unilateral blinding, and not to dislocation of the eye.I am indebted to Dr. A. R. Moore both for the suggestion of the problem and for advice during the experiments. 相似文献
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Kinetics for the inhibition of carboxylesterase by malaoxon 总被引:1,自引:0,他引:1
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