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61.
L. A. Baker P. L. Brezonik E. S. Edgerton R. W. Ogburn III 《Water, air, and soil pollution》1985,25(2):215-230
Acid neutralizing capacities (ANC) of sediments from McCloud Lake, Florida and seven other lakes in Wisconsin and Florida were as high as 10 meq 100 g?1 over the pH range 4.5 to 5.5 in well-mixed batch experiments. Exchange of Ca2+ and Mg2+ accounted for over 50% of the neutralizing capacity; Al solubilization and sulfate adsorption were unimportant in neutralizing H+ additions. ANC was correlated with sediment volatile solids content. Sulfate reduction occurred in microcosms that simulated lake-water interactions and subsurface seepage;in situ pore water profiles and a whole-lake mass balance confirm the occurrence of this process in McCloud Lake. Sediment neutralization is important for lakes that receive most of their water from precipitation and thus are particularly susceptible to acidification. 相似文献
62.
John R. Baker Augustin M. Jones Tessa P. Jones Hugh C. Watson 《Biological conservation》1981,20(4):311-321
Following an oil spill at Sullom Voe Oil Terminal, Shetland, at least 13 otters died. Post-mortems on five corpses showed that they had died of haemorrhagic gastroenteropathy, associated with ingested oil. The primary cause of oil ingestion seems to have been grooming of the fur. A survey of the polluted coasts revealed that otters were still present throughout most of the area. 相似文献
63.
Reserve corridors in production forestry landscapes are frequently concentrated in riparian areas. This study describes the numerical response of ground-dwelling beetles to increasing distance from streams, with the aim of evaluating the effectiveness of such a bias in reserve allocation. Patterns in abundance and diversity of epigaeic beetles were quantified at four first order streams in wet eucalypt forest in Tasmania, Australia. The depth and pattern of beetles’ riparian response varied between streams. Commonly trapped beetles were less abundant near to three of the four streams, and the numerical response model differed in each case. Species richness of common beetles was also lower near one of the streams. Pooled abundance and richness of rare species did not vary in response to the riparian-upslope transition. No riparian or upslope specialist species were identified among the most commonly collected species. Compared to upslope habitat, the riparian-upslope transition encompassed greater variability in species composition without actually increasing overall richness. The study findings demonstrate the need for ecosystem-specific data to optimize reserve placement, since the results were not predicted from general vegetation patterns, ecological theory, or the widely held assumption that riparian areas support greater abundance and diversity of organisms than adjacent upslope areas. Reserves encompassing more upslope habitat are recommended to complement those located in riparian areas. 相似文献
64.
Cataclysmic flooding is a geomorphological process of planetary significance. Landforms of flood origin resulted from late Pleistocene ice-dammed lake failures in the Altay Mountains of south-central Siberia. Peak paleoflows, which exceeded 18 x 10(6) cubic meters per second, are comparable to the largest known terrestrial discharges of freshwater and show a hydrological scaling relation to floods generated by catastrophic dam failures. These seem to have been Earth's greatest floods, based on a variety of reconstructed paleohydraulic parameters. 相似文献
65.
Baker M 《Science (New York, N.Y.)》1999,284(5413):410
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