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Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), Australian School of Environmental Studies, change due to natural and human factors. The study area, located within the Native Dog Creek sub-catchment of the Logan River - which drains into Moreton Bay, south east Queensland - holds a detailed history of environmental change spanning most of the Holocene epoch. This history is preserved in the estuarine sedimentary record and is a valuable indicator of natural environmental change. More recently, human-induced changes within the study area have been superimposed on the natural process of environmental change. In order to develop a conceptual bio-geomorphic model of the coastal wetlands of Native Dog Creek, this thesis examined - on an integrated catchment basis - the evolution and connectivity of four coastal wetland community types (Melaleuca, Casuarina, saltmarsh and mangroves). The research consisted of four discrete studies within the study area: a geomorphic investigation that provided a framework for understanding how the wetlands evolved during the Holocene epoch; an acid sulfate soil (ASS) study that surveyed the distribution and concentration of sulfides; a palynological study that examined the natural directions of ecosystem change; and an investigation of the impact of specific human activities on these ecosystems. Detailed stratigraphic modelling found that the Logan River system (and its Native Dog Creek sub-catchment) has evolved from an infilling estuary since the peak of the Holocene transgression 6500 years before present. Recognition of the major controls that influenced geomorphic coastal development during the Holocene, provided important insights into the distribution and genesis of estuarine pyritic sediments which strongly influence the soils within the study area. In general, the estuarine central basin and fluvial delta sediments posed the greatest risk to the environment from acidification if disturbed. The major focus of the ASS study was to survey the distribution of ASS and to identify other areas most vulnerable to acidification.

The functions HE and VE have been measured between 293.15 and 303.15 K for the mixtures of (±), (+) and (-) 3 methylhexane with carbon tetrachloride, using improved calorimetric and dilatometric systems. As expected, it is found that the excess functions are identical for the optical isomers, within experimental error.

The functions HE and VE have been measured at 303.15 K. for the mixtures of methanol with (±), (+) and (-) octan-2-ol. As expected, it is found that the excess functions are identical for the optical isomers, within experimental error. The volume of mixing of the ( +) and ( —) isomers is also found to be equal to zero.