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471.
Environmental and Ecological Statistics - 相似文献
472.
For this study, field measurements of current profiles, buoy trajectories and the lag of two tidal stations were performed to explore the flow characteristics of Taichung Harbour. in order to distinguish the effects of wind drift current on circulation inside Taichung Harbour, field surveys during both summer and monsoon (winter) season were completed separately. the speed of the drift current was about 3.5% that of the, wind speed, based on the field data. the horizontal dispersion coefficients were close to Bowden's (1965) formula for the tidal current. the water temperature showed a two-layer profile, with the mixing thickness about 4 to 6 metres for the upper layer. the corresponding Richardson number was about 70. the tidal lag between the two tidal stations was 9.68 minutes. All the results agree well with the theoretical results. 相似文献
473.
Use of otoliths and eye lenses for measuring trace-metal incorporation in fishes: a biogeographic study 总被引:1,自引:0,他引:1
The otoliths and lenses of the temperate damselfish Parma microlepis (Günther) (Pomacentridae) showed similar differences in trace-metal profile for selected locations along the coast of New
South Wales, Australia. Otoliths and lenses displayed a differential ability to accumulate metals. Metal concentrations were
ranked differently in the two structures (e.g. Sr > Ba > Pb > Rb > Hg in otoliths, and Hg > Sr ≃ Rb > Pb > Ba in lenses),
and where similar metals were accumulated, they were accumulated at vastly different concentrations (e.g. Ba concentrations
in otoliths are a thousand-fold greater than in lenses). Analyses of the otoliths and lenses of P. microlepis from locations close to Sydney and up to 100 km from the city were able to distinguish amongst these locations with respect
to a number of metals, namely Ba, Mn and Hg. Multivariate analyses of otolith and lens data gave similar results among locations
(agreement was obtained for 11 out of 15 pair-wise comparisons), and differences were attributable to the differential ability
of the two structures to accumulate metals such as Mn and Hg. Trace-metal differences between locations were found to coincide
with the proximity of sewage (including industrial waste) and petroleum storage facilities to the different locations.
Received: 23 June 1997 / Accepted: 4 August 1997 相似文献
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