The meiobenthos of five mangrove vegetation types in Gazi Bay, Kenya

The vertical distribution of meiofauna in the sediments ofAvicennia marina,Bruguiera gymnorrhiza,Ceriops tagal,Rhizophora mucronata andSonneratia alba at Gazi Bay (Kenya), is described. Seventeen taxa were observed, with highest densities in the sediments ofBruguiera (6707 ind. 10 cm−2), followed byRhizophora (3998 ind. 10 cm−2),Avicennia (3442 ind. 10 cm−2),Sonneratia (2889 ind. 10 cm−2) andCeriops (1976 ind. 10 cm−2). Nematodes accounted for up to 95% of total densities; other common taxa were copepods, turbellarians, oligochaetes, polychaetes, ostracods and rotifers. High densities occurred to about 20 cm depth in the sediment. EspeciallyCeriops sediments show still high densities of nematodes (342 ind. 10 cm−2) and copepods (11 ind. 10 cm−2) in the deepest layer (15–22 cm). Particle size and oxygen conditions were major factors influencing meiobenthic distribution;Uca burrows had a major impact on distribution and abundance of meiofauna.