Unusual phosphorus concentrations in the Florida 'red tide' sea water

The total phosphorus content of waters off Florida, USA containing dense Gymnodinium, populations was found to be 2% to 10 times the maximum to be expected in the sea. The possibility that upwelling of nutrientrich, deep water is the explanation of this intense plankton bloom is thereby excluded. It is suggested that future studies of intense plankton blooms include total phosphorus determinations at various depths. The results would differentiate between terrigenous contamination and swarming of the organisms at the sea surface..