49 resultados para AK32-3382
em Publishing Network for Geoscientific
Resumo:
Biogeochemical reef studies carried out in 1981 and 1984 found low concentration of total natural and anthropogenic hydrocarbons in inshore waters. Detection of lignin in marine and bottom sediments indicates that the land has major effect on makeup of organic matter there. Comparison of compositions of organic matter in sea water, suspended matter and bottom sediments indicated that it was altered rapidly by the reef community. Thus, in the inshore zone of the island, runoff from the land is important in supplying nutrients to the reef ecosystem alongside with transport of nutrients by deep waters. Concentrations of nutri¬ents (N, P) in the inshore zone are higher than in waters of the tropical part of the ocean. Nitrogen is the limiting element in development of phytoplankton in the inshore zone.
Resumo:
Lipid contents both in particulate matter and bottom sediments decreases with passage from the shelf toward the open ocean. Lipid concentration in particulate matter collected by a separator (Ls) decreases by a factor of 7 (from 7.05 to 0.95 % of dry matter), while in particulate matter collected on filters (Lf) it decreases by a factor of 13 (from 78 to 6 µg/l) in the vicinity of the Limpopo River and by a factor of 6 (from 74 to 13 µg/l) in the vicinity of the Zambezi River. Concentration of Lf also decreased with depth. In the upper sediment layers lipid concentration was 0.0028-0.039% of dry matter; all mud samples were richer in lipids, than sand samples. During sedimentogenesis there is an increase in proportion of lipids relative to other classes of organic matter, proportion of low-polarity compounds increases among the lipids, and proportion of hydrocarbons rises among these compounds. Sediments inherit composition of particulate matter to the greatest degree in the vicinity of river mouths.
Resumo:
Compositions of different types of ocean suspended matter are under consideration.
