An Ecophysiological Study of the Meiofauna of the Swartkops Estuary

Abstract

Benthic oxygen demand was measured by dark and light bottle technique at two beaches in the Swartkops estuary, near Port Elizabeth. Respiration of nematodes was measured by polarographic micro-rcspirometer technique. Secondary production was 82 g C/m²/y in sandy areas and 863 g C/m²/y in muddy areas rich in the prawn Callianassa kraussi. Meiofauna production was 1,72 g C/m²/y in sand and 0,24 g C/m²/y in mud. The meiofauna] contribution to secondary production was 2,1% and 0,03% for these two areas respectively. The largest proportion of secondary production was due to micro-organisms: 92% in sand and 73,5% in mud. Macrofauna accounted for 5,75% and 24,4%. It is concluded that meiofauna in these exposed sand and mud flat areas is not quantitatively important, but the qualitative importance may be considerable.