The effects of sediment from an industrial outfall area on a marine planktonic ecosystem

Sediment from Xiamen industrial area was added to marine ecosystem enclosures to test the effects on the planktonic communities in Xiamen Bay, China, in April, 1985.Sediments were added at two concentrations, 11.2 and 112 ppm dry wt.respectively.The species of phytoplankton did not change as compared with the control, but the number of diatoms markedly decreased in the sediment treated enclosures.A suppression of photosynthesis was presumed to be due to light attenuation by the added sediment.Microflagellates, zooplankton and bacteria were resistant to sediment increase in water column.