The distribution of benthic foraminiferal assemblages in the north-west coastal region of Malacca Straits,Malaysia

Objective:To investigate the spatial and temporal distribution of benthic foraminiferal assemblages in relation with environmental parameters in Penang Island(the northern part of Malacca Straits,west coast of Peninsula Malaysia).Methods:Foraminifera samples were obtained from 144 sediment samples collected bimonthly throughout a one year sampling period using Ponar grab.These samples were then fixed with 4%buffered formalin stained with Rose Bengal.Temperature,salinity,dissolved oxygen and pH were detected in-situ at six sampling points within each transect approximately one metre above the seafloor.Sediment samples collected was also used to determine particle size.Results:A total of fourteen benthic foraminiferal genera obtained from two major groups belonging to the calcareous and agglutinated groups have been identified at all four sampling locations throughout the sampling period.The abundance of 13 out of 14 species were significantly affected by different sampling sites and times(P<0.05).Physicochemical variables comprising temperature,salinity,dissolved oxygen and pH differed among sites and sampling months(P<0.05).Conclusions:The distribution of foraminifera in terms of abundance and presence of species indicated dominance by calcareous genera of foraminifera contributed by significantly great abundances of Ammonia sp.and relatively low abundance of agglutinated taxa.This pattern of distribution could indicate a close association between foraminifera and physicochemical parameters.