Factors Influencing Algae–Clay Aggregation (original) (raw)

Relationship between antropogenically caused turbidity and phytoplankton production in a clear Amazonian floodplain lake

2002

The present study wâs performed in Lake Batata, a clear water Amazonian floodplain ecosystem, located on the right bank of the Trombetas river (Pará State,. Brazil). For a period of l0 years (1979-1989), the lake received a large quantity of bauxite tailings from a nearby mine. These tailings originally covered about 30 To oî the lake sediments, but resuspension and redeposition have resulted in an even wider distribution ofthe tailings. Phytoplankton production was measured at dìfferent sites in naturaI an in.rpacted areas at different hydrotogical phases. Incubations were exposed at 5 light depths using raC as tracer. All vertical profiles of primary production exhibited ca. 13 %à light inhibition in the surface. The maximum primary production rates (Pmax) were always found near the surface at approximately 30 cm. Production rates ranged from 9 to 664 mgC mr d-', being the higher rates found during low water and lower rates during high water periods. Transparency measurements ...