ENVIRONMENTAL CONTROLS ON BENTHIC FORAMINIFERAL AND THECAMOEBIAN ASSOCIATIONS IN A NEW-ZEALAND TIDAL INLET

Census data on benthic foraminiferal and thecamoebian tests in 52 surf ace sediment samples from Purakanui Inlet, Otago, New Zealand, are ana lyzed by cluster and correspondence analyses, Faunas are grouped into 10 sample associations with the following characterizing species: A) T rochammina inflata-at or above mean high water level in high salt mead ow, salt marsh or grass; B) Jadammina macrescens/Trochammina inflata-a t or above mean high-water level on the edge of high salt meadow; C) T rochamminita salsa-in sandy soil at around mean high-water spring, pos sibly influenced by fresh groundwater seepage; D) Pontigulasia compres sa/Trochamminita salsa/Difflugia capreolata-at high tide level in the bed of the main freshwater stream flowing into the inlet; E) Haplophra gmoides wilberti-in salt marsh and grass at mean high-water level on t he edge of the inlet; F) Miliammina fusca-in Sarcocornia muddy, low sa lt meadow and sandy mud flats between mid and high tide levels; G) Elp hidium excavatum-ver a wide area of tidal sand flats in the upper and middle parts of the inlet; H) Ammonia beccarii/Elphidium excavatum-in three areas of tidal sand hat in association with G, but with slightly lower salinity and nutrients; I) Elphidium excavatum/haynesina depres sula-intertidally and subtidally around the inner end of the entrance channel in the vicinity of the flood tide sand delta; J) Zeaflorilus p arri-intertidally and subtidally in the shallow, current swept entranc e to the inlet, These correlate closely with the 8 species association s produced by cluster analysis. Canonical correspondence analysis indi cates that the following factors in decreasing order of importance are most influential in determining the faunal distribution: tidal exposu re, salinity, percentage of mud, proximity of the open sea, organic ca rbon, phosphate and intertidal vegetation type.