CHEMICAL-COMPOSITION OF PHYTOPLANKTON AND PARTICULATE ORGANIC-MATTER IN THE RIA DE VIGO (NW SPAIN)

Elemental(C, H, O, N, Si, P) and biochemical composition (proteins, ca rbohydrates, lipids, phosphorus compounds, chlorophyll and opal) in pa rticulate organic matter, diatoms, other autotrophs, heterotrophs and detritus from natural plankton were established simultaneously by meas uring relatively few components. Using standard techniques in marine c hemistry on board ship, it is possible to infer a great deal about the composition and condition of the plankton. In addition, the organic m atter content in terms of cell volume was determined for each group of plankton. Variation of chemical composition with depth was also consi dered. The ratio carbohydrates/lipids (Cbh/Lip) was used as an indicat or of the chemical quality of the plankton.