Planktoniska

Planktoniska is an adjective used to describe organisms or communities associated with plankton, the drifting or weakly swimming life in the water column. The term is commonly used in Swedish to translate the English word planktonic, which derives from the Greek planktos meaning wanderer. In biology, planktoniska organisms are characterized by limited ability to swim against currents over long distances, relying largely on water movement for transport.

Planktoniska communities encompass a wide range of life, including phytoplankton (unicellular algae and other photosynthetic organisms) and zooplankton (small animals and their larvae). Examples range from diatoms and dinoflagellates to copepods and jellyfish larvae. Many planktoniska organisms occupy distinct vertical zones, with populations shifting in response to light, nutrients, and predation.

Ecologically, planktoniska organisms form the base of aquatic food webs and play a crucial role in global biogeochemical cycles. Phytoplankton contribute to primary production and carbon fixation, while zooplankton transfer energy to higher trophic levels. Diel vertical migration, where some planktonic organisms move up and down the water column daily, can influence nutrient cycling and predator–prey dynamics.

Human relevance includes climate regulation through carbon sequestration, support for fisheries via food webs, and the use of planktonic indicators to monitor environmental change. Researchers study planktoniska communities through tows, net samplings, acoustic surveys, and satellite-based measurements of chlorophyll as a proxy for biomass.