The value of plankton

The term “plankton” encompasses a wide range of organisms from the smallest virus and bacteria, through small and large phytoplankton (photosynthetic drifting algae), to small and large zooplankton (copepods, shrimps, jellyfish, and the larvae of bivalves, crabs, and fish), with an equally broad range of ecosystem services.

  • Provisioning services (e.g. aquaculture, natural aquatic biomass, genetic materials)
  • Regulating and maintenance services (e.g. climate regulation, water purification, nursery population and habitat maintenance)
  • Cultural services (e.g. recreation-related, education, scientific and research)
  • Non-use services (i.e. “existence”, e.g. ecosystem and species appreciation)
Plankton are the natural capital that underpins critical ecosystem services.

Pelagic Natural Capital indicators, tools, and the Lifeform approach

The diversity of species of plankton is simplified by grouping species into “lifeforms”. They are all thought to have major functional roles in the Pelagic Habitat, though not all roles are well understood in ecological terms. In terms of ecosystem services it is only a sub-set of lifeforms (e.g. diatoms, dinoflagellates, coccolithophores, copepods, euphausiids and jellies) about which we know enough to specify their contribution to human well-being.

Around these we are designing a number of tools to help natural capital decision making including:

  • Eutrophication and harmful algal bloom reviews
  • Available and unavailable carbon in the plankton (“food for shellfish”)
  • Fish and pelagic food – top down or bottom controls?
  • Size spectra as indicator of carrying capacity for fish stocks.
  • Changing balances in food webs – why are meroplankton dominating?