Successional Change in the Planktonic Vegetation: Species, Structures, Scales

Abstract

Plankton is the community of plants, animals and microbes which are adapted to live suspended in the pelagic of lakes and seas and which are liable to passive entrainment within the motion of the water. As is the case in terrestrial communities, such as forests or grasslands, planktonic communities, actually or potentially, comprise a considerable diversity of species with a variety of phylogenetic affinity, primary function, physiology, size and ecology. As our knowledge of pelagic organisms has steadily increased, however, it has become more difficult to make rigid distinctions between the phytoplankton, Zooplankton and bacterioplankton and it has accordingly become less easy to distinguish the analogous community structuring of the communities. Moreover, debates have continued about the relative mechanistic roles of the autotrophs and heterotrophs in underpinning the biogeochemical processes upon which they impinge. In this paper, I attempt to show, primarily by reference to the freshwater pelagic photoautotrophs, how the adaptations of individual organisms influence the manner in which communities are assembled and altered through time and how, apart from the temporal and spatial scales at which they operate, these developments provide model examples of terrestrial vegetation processes. As the principal plant-life of open water, I seek to establish the propriety of referring it as pelagic vegetation.