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Cores of sediment from Nee Soon, a peat-forming freshwater swamp located in the perimarine zone of Singapore, have yielded a record of vegetation history that comprises parts of the last glacial and Holocene periods. The evidence includes two conventional and four AMS radiocarbon dates, the oldest of which is 23,050±330 B.P. (uncalibrated radiocarbon years), and variations in the abundances of sub-fossil pollen and spores and charcoal. The results of a study of the relationship between contemporary vegetation and modern pollen accumulation facilitated interpretation of sub-fossil tree pollen data. Peat formation occurred at Nee Soon during the last glacial, when sea levels on the Sunda continental shelf were well below those at present. The occurrence of montane pollen types, notably Podocarpaceae, in sediment samples dated to the late glacial and early Holocene suggests either temperatures substantially lower than those of the present and, possibly, humid conditions, or cold, seasonally dry climates and reduced levels of atmospheric CO 2 . The abundance of charcoal indicates the widespread occurrence of fires throughout the entire period represented by the cores. For the mid Holocene, the evidence indicates an increased saline influence, presumably as a result of relatively high sea levels. Falling sea levels during the late Holocene appear to have preceded the onset of the most recent period of peat formation at Nee Soon. The evidence confirms that long (last glacial–interglacial) records of lowland vegetation history are available from terrestrial locations in the humid core of Southeast Asia and suggests that the complexity of perimarine swamp dynamics is not captured fully by Anderson's model, which assumes a close relationship between peat formation and sea level.

The morphology of landforms on the south coast of Western Australia is determined predominantly by wave refraction around discrete headlands and islands. Wherever offshore structures protect the shore from the direct effects of swell, sheltered sandy beaches have developed in association with cuspate forelands and tombolos. In contrast to this open coast setting, the nearshore waters of the west coast are protected by semi-continuous reef systems, which significantly modify the morphology of large-scale accretionary landforms, beaches and foredune sequences. On the south coast, foredune plains occur primarily as fill in sheltered embayments and storm built ridges do not occur. Foredunes on the west-coast include washover ridges and low aeolian dunes on the backshore of embayment and inset beaches. The form of high wave-energy beaches of the south coast fluctuates between reflective and dissipative morphodynamic states, and most commonly between transitional and dissipative states. Sediments are mainly fine grained siliceous sands. In contrast, the low-energy west-coast beaches are composed of medium to coarse grained, calcareous sands. The beaches are planar in section, characterised by lines of debris deposited by tidal and longer-term fluctuations in sea-level and their form does not alter with short-term changes in the wave regime. Despite the very low energy micro-tidal conditions experienced by the coasts of southwestern Australia, systematic variation in the morphology of coastal landforms does occur. As protection to the coast increases from the open-fetch south-coast environment to the reef-protected west-coast setting, swell energy decreases, there is an increase in the relative importance of locally generated wind waves, wave set-up and tidal forcing of currents, and forelands become increasingly asymmetric due to the strength of longshore sediment transport.

Variability in the regional setting and morphology of cuspate forelands on the west coast of Western Australia is examined in this paper. In accordance with this aim, principal differences in the geologic and geomorphologic setting of three prominent sites on the west coast were established and their association with historical changes and contemporary oceanographic processes was examined. The cuspate forelands investigated are Jurien Bay, Winderabandi Point and Turquoise Bay. The most significant differences in geologic setting are associated with the structure and location of an extensive offshore reef system. Morphologically, the reef alters from south to north, changing from a discontinuous ridge parallel to the shore along the central west coast, to a nearly continuous fringing reef at Ningaloo. The reefs vary in distance from the shore, being farthest in the south and closest in the north and they impound a series of inshore basins, or lagoons. The deeper southern basins are dominated by locally generated wind waves and wind-generated currents. The shallower northern basins are most markedly affected by tidal currents and wave pumping across the reef flats. The large cuspate foreland at Jurien on the central west coast has undergone shoreline configuration change in response to changing phases of storminess as well as in response to a change in focus for sediment deposition as a result of offshore reef erosion. At Winderabandi Point on the Ningaloo coast, relict Pleistocene limestone has provided the focus for sedimentation and morphology has been controlled by a balance in refracted wave energy and nearshore currents driven by tidal and wave set-up variability. At Turquoise Bay, where the lagoonal basin is most shallow and narrow, the morphology of the foreland suggests that it may at some stage have been migratory, but its present asymmetrical shape is maintained by strong northerly longshore drift and strong currents exiting the lagoon through a nearby gap in the reef crest. Fundamental differences between the two coastal regions include the structure of the offshore reef, processes driving flow of water within the lagoons and the role of storminess in evolution of coastal landforms. Although many questions regarding storm surge dynamics and landform change remain unanswered, this research provides a significant contribution to the understanding of the evolution of morphological systems in low-wave-energy protected environments. Copyright © 2000 John Wiley & Sons, Ltd.

Identification of littoral cells is a prerequisite for the determination of sediment budgets on sandy coasts. In this context, the aims of the project were, first, to investigate the applicability of statistical techniques, particularly auto-correlation and cluster analysis, to the definition of littoral cell boundaries; second, add detail to sedimentological and environmental observations previously reported for the southwestern Australian coast; and third, provide a basis for future examination of sediment transport in a nearshore environment that is generally subject to low wave energy. The alongshore component of sediment compartmentalisation has been determined for the sandy beaches of the study area and relationships between environmental parameters and beachface sediment characteristics have been established. Using data describing textural and compositional attributes, the systematic alongshore variation in sediments was determined from the cluster analysis and auto-correlation. Results from the grouping of sediments were then used in conjunction with geomorphic variables to determine boundaries of six sediment compartments. Littoral cells are better developed on the southern sector of the coast where shoreline salients and headlands are larger and act as boundaries. These barriers limit, but do not prevent, inter-compartment sediment transport. The findings of this study provide a context for further investigation of littoral cell dynamics and coastal sediment transport. The statistical techniques applied to data describing the alongshore distribution of sediments are readily repeatable in other contexts and have general applicability and offer a rigorous procedure for definition of coastal regions.

In this study we evaluated, in our residency program, the understanding and management of a simulated oxygen pipeline failure. Performances of 20 residents were evaluated by 2 raters. Fourth-year residents did not perform better than second-year residents (P = NS). The majority of the participants either did not have the knowledge to change the oxygen cylinder or did not attempt to change the oxygen, even after prompting. We conclude that the delegation of gas machine maintenance to perioperative personnel, such as respiratory therapists and technicians, may have created a new gap in knowledge and resulted in inadequate training.