Outreach

Meiofauna is defined by size based on the standard mesh width of sieves with 500 - 1000 µm as upper and 32 - 63 µm as lower limit.

The meiofauna has representatives from 23 phyla and is therefore more phylogenetically diverse than any other component of the marine biota. This initially subjective size-range of benthic invertebrates has since been shown to represent a discrete, ecologically defined group of organisms whose morphology, physiology and life-history characteristics have evolved to exploit the interstitial matrix of marine sediments (see: Meiofauna pictures).

Compared to the macrofauna, meiofauna has a low standing stock. Nevertheless, the higher turn-over rate of meiobenthos usually generates a high production, frequently exceeding that of macrofauna. In undisturbed environments, meiofauna (with nematodes and harpacticoid copepods dominating) have been calculated to consume twice the amount of carbon and to produce four times as much as the macrofauna with only about half its biomass. It seems as if for the comparatively slowly growing macrofauna, the fixation of energy is dominating whereas for the smaller meiofauna, the production and turn-over of energy is paramount.

Due to their high abundance and diversity, omnipresent distribution, rapid generation times and fast metabolic rates, they have an important role in ecosystem functioning. Thus the state of meiofaunal assemblages may reflect the overall health of the bottom of the sea.

Meiofauna can be found in all marine (from the beach to the deep sea, and from the poles the equator) and estuarine environments, can be maintained in relatively small volumes of sediment. Additionally, they have short life-cycles (1 to 3 months) so that changes in community structure can be observed in short-term studies.
Therefore, the use of meiofaunal assemblages to assess the effects of natural and man-made perturbations in marine ecosystems has increased significantly.

As a consequence of the changing climate, an increase in the frequency and intensity of storms is expected, bringing along an important higher amount of rainfall. This will impact organisms that are adapted to life in marine environments.

Meiobenthic organisms encountered immediately above the swash zone of beaches are dominated by marine organisms. These are adapted to the alternating influence of the tides and can overcome short term periods of fresh water input (rainfall during low tide). Marine nematodes, even of intertidal areas, will however explode in fresh water environments due to osmotic stress.

The experimental sites are located at

Arina

De Panne

Hel

Sines