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1. The different geological formations and their ecouomie sigmficances. (a)Alluvium (b)Loess (c)Red beds (d)Upper coal series and Sandstone formations (e)Lower coal series (f)Metamorphic series 相似文献
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Hunt B 《Ground water》2008,46(4):529-30; discussion 530-1
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Small amounts of oil that can persist for decades in the intertidal zone of coarse-sediment beaches have been documented in a few well-studied cases. Oil that survives attenuation over the short-term (weeks to months) will persist until there is a change in the environmental conditions, as might occur where there is a seasonal storm-wave climate or as a beach undergoes long-term (erosional) changes. Oil residues can persist on the beach surface as tar mats, asphalt-like pavements, or as veneers on sediment particles or hard surfaces. Subsurface oil residues can persist in similar forms or as fill or partial fill of the pore spaces between coarse-sediment particles. Oil penetrates until it reaches fine-grained sediment, the water table, bedrock, or other penetration-limiting layers. Amounts of persistent oil are very small fractions of the volumes that were originally stranded and these protected residues can continue to biodegrade as they become thinner and more discontinuous. 相似文献
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First results on the study of metal contamination along the Corsican coastline using Posidonia oceanica 总被引:1,自引:0,他引:1
This study aims at determining the metal concentrations in blades and sheaths of Posidonia oceanica adult leaves, in 16 stations of the Corsican coastline. It shows that except for Cr, all the metals are preferentially accumulated in the blades. This result is particularly interesting as it means that trace metals analyses may be carried out only on the blades avoiding thus the removal of the shoots. Moreover, this study shows that metal concentrations generally fall within the range of the lowest values available in literature and may reflect the "background noise" of the Mediterranean. Station 15 (Canari) can however be distinguished from the others due to its high Co, Cr and Ni concentrations. This result may be related to the presence of a previous asbestos mine, located near this station. Therefore, this study reinforces the relevance of the use of P. oceanica as a tracer of metal contamination. 相似文献
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Ziskowski J Mercaldo-Allen R Pereira JJ Kuropat C Goldberg R 《Marine pollution bulletin》2008,56(4):740-750
Winter flounder from New Haven, Connecticut were evaluated for fin rot disease. Blood samples collected from healthy and diseased fish were used to measure bilirubin, calcium, hematocrit, inorganic phosphorus, osmolality, and total protein. Blood measurements were significantly affected by the presence of fin rot disease and by sampling mode (bled immediately or after 18 h). A reduction in blood chemistry values was associated with fin rot disease. Logistic regression modeling was used to identify explanatory variables contributing to the fin rot outcome in winter flounder. Blood constituent levels were higher in fish bled immediately versus 18 h post-capture, especially among fish without fin rot, suggesting that a waiting period is necessary for blood values to stabilize following initial sampling stress. This study presents evidence that winter flounder blood chemistry and hematocrit measurements are affected by fin rot disease. 相似文献
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