DETERMINATION OF MICROBIAL BIOMASS IN OCEAN PROFILES1

Abstract

Total particulate carbon, nitrogen, adenosine triphosphate (ATP), deoxyribonucleic acid (DNA), and chlorophyll have been measured in detailed profiles to 600 and 1,000 m off the coast of southern California. Biomass estimations based on chlorophyll and ATP measurements were in excellent agreement with those estimated by direct examination. Because of the large amounts of DNA in the detrital fraction, it cannot be used as a biomass indicator. Below 200 m, the concentrations of total particulate carbon and nitrogen were fairly uniform, averaging about 7 µ g C/liter and 0.6 µ g N/liter.