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Quantitative analyses of recent benthic foraminiferal assemblages (living and dead) were carried out on the surface sediments of Sulaibikhat Bay. Marked contrast in foraminiferal assemblages between the shallow tidal mudflats and the deep tidal channel and their relation to the extent of pollution were observed. Cluster analysis of quantitative data on the distribution of foraminiferal tests revealed three assemblages that depend mainly on the intensity of pollution; (1) a highly polluted tidal flat assemblage, (2) normal (or less polluted) mud flat assemblage and, (3) tidal channel and subtidal assemblage. The highly polluted assemblage characterized by a drop in species densities (< 100 tests/20 cm(3) sediment) but with high average diversity (5.8 Yule-Simpson Index). The microfauna of the less polluted flat displays relatively lower diversity (4.6) but high density of tests (47.2% of the total picked tests). The most abundant species of this assemblage is Ammonia tepida, displays its maximum density in this assemblage. Ammonia tepida drops in density from 17.12% to 3.07% in the polluted assemblage. Tidal channel foraminiferal assemblages should normally display lower diversities than those of tidal flats, because tidal current in the channels tend to wash away most nutrient materials. However, this is not the case of the present study area which could be due to environmental setting of the Sulaibikhat Bay in which tidal currents bring in exceptionally high amounts of nutrients from Shatt Al-Arab Estuary and in which the tidal flats are strongly and adversely polluted.

AL-ZAMEL, A.; AL-SARAWI, M., and KHADER, S., 2007. Coastal geomorphology, hydrodynamics, and biolithofacies in the intertidal and subtidal area of Umm Al-Namil Island, Kuwait Bay, Kuwait. Journal of Coastal Research, 23(2), 501-514. West Palm Beach (Florida), ISSN 0749-0208.Umm Al-Namil Island is one of the small northern islands of the State of Kuwait located within Kuwait Bay. A series of six beach profiles were surveyed and seven N-S transects were constructed during the period between 1998 and 2005 to study the grain-size distribution and biogenic activities around the island. Sediment samples were monitored and analyzed for short-term changes. Beach sediment consists of fine-medium oolitic to biogenic sand with a high percentage of coarse grain clastics and shell fragments, which occur mainly in the northern part of the island. The estuarine depositional environments include tidal channels, hardground reefal flats, tidal mud flats, spits and sand bars that are seen to interfinger with shoreline and inner coastal deposits of the island. Changes in the profiles were observed in the southern part of the island where some recurved spits have formed and accumulation of sediment persists. Beach changes were also observed in the northern side of the island. Six principal communities of organisms dwell around the island, and these contribute to the major part of the recent biogenic sedimentation. Cluster analysis of the quantitative data on sediment faunal interrelation of 30 samples enabled us to recognize three biolithofacies units. Study of common foraminiferal and ostracod species in the area indicates that the distribution and dominance of different benthic species have relatively simple patterns that are governed by water depth, salinity, hydrodynamic conditions, and sediment size.

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