Journal of the Marine Biological Association of the United Kingdom

Research Article

The Size Structure of Deep-Sea Meiobenthos in the North-Eastern Atlantic: Nematode Size Spectra in Relation to Environmental Variables

T. Soltwedela1, O. Pfannkuchea2 and H. Thiela1

a1 Alfred-Wegener-Institut für Polar- und Meeresforschung, Columbusstraβe, 27515 Bremerhaven, Germany.

a2 Forschungszentrum für Marine Geowissenschaften, GEOMAR, Wischhofstraβe 1–3, 24148 Kiel, Germany

The size distribution of benthic nematodes was investigated along different gradients of food availability in various regions of the north-eastern Atlantic: I, across the continental margin and II, with increasing distance from the continental rise. An overall trend for miniaturization with increasing distance from the food source was found. Moreover, our results indicate that seasonally varying food supply or a periodically pulsed input of organic matter to the sea floor affects nematode size spectra. The hypothesis is proposed that the life cycle of deep-sea nematode species and hence the size structure of their populations are related to seasonal energy availability. This dependence might result in one year life spans of deep-sea nematodes and probably other meiofauna.