Williams et al. (2009) report on new multibeam sonar bathymetry and underwater video data collected from submarine canyons and seamounts on Australia's southeast continental margin to 'investigate the degree to which geomorphic features act as surrogates for benthic megafaunal biodiversity' (p. 214). The authors describe what they view as deficiencies in the design of the Marine Protected Areas (MPAs) in the southeast region of Australia, in which geomorphology information was employed as a surrogate to infer regional-scale patterns of benthic biodiversity. This comment is designed to support and underscore the importance of evaluating MPA designs and the validity of using abiotic surrogates such as geomorphology to infer biodiversity patterns, and seeks to clarify some of the discrepancies in geomorphic terminologies and approaches used between the original study and the Williams et al. (2009) evaluation. It is our opinion that the MPA design criteria used by the Australian Government are incorrectly reported by Williams et al. (2009). In particular, we emphasise the necessity for consistent terminology and approaches when undertaking comparative analyses of geomorphic features. We show that the MPA selection criteria used by the Australian Government addressed the issues of false homogeneity described by Williams et al. (2009), but that final placement of MPAs was based on additional stakeholder considerations. Finally, we argue that although the Williams et al. (2009) study provides valuable information on biological distributions within seamounts and canyons, the hypothesis that geomorphic features (particularly seamounts and submarine canyons) are surrogates for benthic biodiversity is not tested explicitly by their study.

Summary of last 12 months activity in Acreage Release Area.

Spatial interpolation methods have been applied to many disciplines. Many factors affect the performance of the methods, but there are no consistent findings about their effects. In this study, we focus mainly on comparative studies in environmental sciences to assess the performance of spatial interpolation methods and to quantify the impacts of data properties on the performance. Two new measures are proposed to compare the performance of the methods applied to multiple variables with different units/scales. A total of 53 comparative studies were assessed and the performance of 61 methods/sub-methods compared in these studies is analysed. The impacts of sample density, data variation, and sampling design on the estimations of 32 methods are quantified using data derived from their application to 80 variables. Inverse distance weighting (IDW), ordinary kriging (OK), and ordinary co-kriging (OCK) are the most frequently used methods. Data variation is a dominant factor and has significant impacts on the performance of the methods. As the variation increases, the accuracy of all methods decreases and the magnitude of decrease is method dependent. Gradient plus inverse distance squared (GIDS), OCK and regression residual kriging (RK-C) are less sensitive to data variation. Irregular-spaced sampling design might improve the accuracy of estimation. The effect of sampling density on the performance of the methods is found not to be significant. The implications of these findings are discussed.

Map produced for the Australian Government Solicitor in July 2009 showing the Torres Strait Regional Claim. Produced for the use of AGS in the their provision of advice regarding native title.

No abstract available

Map produced for the Australian Government Solicitor in July 2009 showing the Torres Strait Regional Claim. Produced for the use of AGS in the their provision of advice regarding native title.

New SHRIMP U/Pb zircon ages of 472.2 ± 5.8 Ma and 470.4 ± 6.1 Ma are presented for the age of peak metamorphism of Barrovian migmatite units. Published U/Pb emplacement ages for Grampianage igneous units of Scotland and Ireland vary between c. 473.5 and c. 470 Ma. Magmatic advection provided significant heat for the Barrovian metamorphism, and the new U/Pb ages are consistent with attainment of peak Barrovian metamorphic temperatures during Grampian magmatism. U/Pb-calibrated 40Ar/39Ar ages for white mica from the Barrovian metamorphic series vary systematically, between c. 465 Ma for the biotite zone and c. 461 Ma for the sillimanite zone. Microstructural work on the timing of peak metamorphism has shown that metamorphism occurred progressively later with increasing peak-metamorphic grade. Younging metamorphic age with increasing metamorphic grade across the Barrovian metamorphic series requires that the sequence was cooled in the lower-grade regions while heating persisted in the high-grade regions. This thermal scenario is well explained by the presence of a large-scale extensional detachment that influenced the thermal regime by actively cooling units from above while metamorphic heating continued below the sequence. The spatio-temporal thermal pattern recorded by the Barrovian metamorphic series is consistent with regional metamorphism during crustal extension.

5 educational posters created for the Sapphire Coast Marine Discovery Centre in Eden on Geomorphology, Geology, Land Use and Type, and Seabed Habitats.

Groundwater monitoring around the CO2CRC Otway Project CO2 injection site aims to (1) establish baseline aquifer conditions prior to CO2 injection, and (2) enable detection monitoring for CO2 leakage, in the unlikely event any should occur in the future. The groundwater composition was monitored at 24 bores around the site for nearly 2 years before injection started. The water samples were analysed for standard bulk properties, and inorganic chemical and isotopic compositions. In addition to sampling, standing water levels were monitored continuously in 6 of the bores using barometric loggers. The shallow groundwaters have compositions typical of carbonate aquifer-hosted waters, being fresh (EC 800-4000 S/cm), dominated by Ca2+, Na+, HCO3- and Cl-, cool (T 12-23°C), and near-neutral (pH 6.6-7.5). Most of the deep groundwater samples are fresher (EC 400-1600 S/cm), also dominated by Ca2+, Na+, HCO3- and Cl-, cool (T 15-21°C), but are more alkaline (pH 7.5-9.5). Time-series reveal that most parameters measured have been relatively stable over the sampling period, although some bores display changes that appear to be non-seasonal. Groundwater levels in some of the shallow bores show a seasonal variation with longer term trends evident in both aquifers.

Spatially continuous data of environmental variables is often required for marine conservation and management. However, information for environmental variables is usually collected by point sampling, particularly for the deep ocean. Thus, methods generating such spatially continuous data by using point samples to estimate values for unknown locations become essential tools. Such methods are, however, often data- or even variable- specific and it is difficult to select an appropriate method for any given dataset. In this study, 14 methods (37 sub-methods) are compared using samples of mud content with five levels of sample density across the southwest Australian margin. Bathymetry, distance to coast, and slope were used as secondary variables. Ten-fold cross validation with relative mean absolute error (RMAE) and visual examination were used to assess the performance of these methods. A total of 1,850 prediction datasets were produced and used to assess the performance of the methods. Considering both the accuracy and the visual examination, we found that a combined method, random forest and ordinary kriging (RKrf), is the most robust method. No threshold in sample density was detected in relation to prediction accuracy. No consistent patterns were observed between the performance of the methods and data variation. The RMAE of three most accurate methods is about 30% lower than that of the best methods in previous publications, highlighting the robustness of the methods selected in this study. The limitations of this study were discussed and a number of suggestions were provided for further studies.