Composition and seasonal fluctuations of meiofauna in a Southern African mangrove estuary

Fluctuations in population structure and abundance of mangrove meiofauna were monitored over a period of 14 months. The greatest mean abundance was directly correlated with mean redox potential (Eh), but showed poor relationships with pH and temperature. Maximum density occurred at the mid to high tide levels and nematodes accounted for 80% of the total numbers. Large ciliates were the next most abundant group accounting for 6.4%. These were followed by oligochaetes (4.5%), turbellarians (3%) and kinorhynchs (2.7%). The remainder consisted of low numbers of copepods, polychaetes, gastrotrichs, the larvae of crustacea (prawns and crabs) and insects. Although there was a tendency for density to increase in summer, the numbers were variable and seasonal correlations with physical parameters were obscure. The estimated production from the standing crop is 4.34 gC m^-2 vr^-1.