Heterotrophic Utilisation of Mucilage Released During Fragmentation of Kelp (Ecklonia maxima and Laminana pallida). I. Development of Microbial Communities Associated with the Degradation of Kelp Mucilage

Abstract

The micro-organisms which colonise seawater incubated with mucilage from the kelps Ecklonia maxima or Laminaria pallida show a clear succession. The media are first colonised by bacterial cocci followed by rods which are subsequently replaced by flagellates and ciliates whose combined biomass reaches some 6-10 % of that of the bacteria. The maximal biomass of bacteria is achieved in 7-10 d incubation at 10 "C but is dependent both on the time of appearance and biomass of the flagellate and ciliate populations. Estimates for the rate of consumption of bacteria by flagellates of only 10 pm3 body volume suggest that mineralisation of bacteria by marine microflagellates may considerably exceed that in larger organisms at higher trophic levels.