Chlorophyll "a" and adenozine triphosphate (ATP) concentrations together with size structure of microplankton were investigated in January-April 1989 in the Indian Ocean and in the Weddell Sea. ATP values varied from 11 to 92 ng/l, and chlorophyll "a" concentrations varied from 0.04 to 0.27 µg/l in the Indian Ocean, with prevailing nanoplankton and picoplankton fractions. Both ATP and chlorophyll "a" concentrations increased 2 times to the south of 40°S; in the Weddell Sea they exceeded 400 ng/l and 0.6 µg/l, respectively. Cells of nanophytoplankton and microphytoplankton (mainly diatoms) prevailed in size spectra. Spatial variabilities of the parameters were within one order of magnitude; their values decreased 3-4 times during 1 month. Size structure changed due to increased portion of nanoplankton and picolankton. ATP concentrations in the photic layer (0-200 m) varied from 31.96 mg/m2 in February to 8.02 mg/m2 in March to April. ATP concentrations were 61.5 and 98.8 mg/m**2 at depths of 4200 and 4700 m, respectively.

Supplement to: Lopukhin, A S (1993): Weddell Sea microplankton (Antarctica): Concentration of intracellular adenozine triphosphate and chlorophyll a: size spectra of parameters. Oceanology, 33(3), 320-328