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2015

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    The data is the percent algal cover derived from underwater visual census methods involving transect counts at rocky reef sites around Tasmania. This data forms part of a larger dataset that also surveyed fish and megafaunal invertebrate abundance for the area. The aggregated dataset allows examination of changes in Tasmanian shallow reef floral and faunal communities over a decadal scale - initial surveys were conducted in 1992-1995, and again at the same sites in 2006-2007. There are plans for ongoing surveys. An additional component was added in the latter study - a boat ramp study looking at the proximity of boat ramps and their effects of fishing. We analysed underwater visual census data on fishes and macroinvertebrates (abalone and rock lobsters) at 133 shallow rocky reef sites around Tasmania that ranged from 0.6 - 131 km from the nearest boat ramp. These sites were not all the same as those used for the comparison of 1994 and 2006 reef communities. The subset of 133 sites examined in this component consisted of only those sites that were characterized by the two major algal (kelp) types (laminarian or fucoid dominated). Sites with atypical algal assemblages were omitted from the 196 sites surveyed in 2006. This study aimed to examine reef community data for changes at the community level, changes in species richness and introduced species populations, and changes that may have resulted from ocean warming and fishing. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. The underwater visual census (UVC) methodology used to survey rocky reef communities was designed to maximise detection of (i) changes in population numbers and size-structure (ii) cascading ecosystem effects associated with disturbances such as fishing, (iii) long term change and variability in reef assemblages.

  • The ETAS (Eastern TASmania) model is a high-resolution (~2 km in the horizontal) ocean model for eastern Tasmania, providing three-dimensional estimates of daily temperature, salinity, and circulation over the 1993-2014 period. This dataset consists of temperature, salinity, along- and cross-shore currents, density and sea level organised into yearly files.

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    Seasonal patterns in the in situ ecophysiology of the common habitat-forming seaweeds Ecklonia radiata, Phyllospora comosa, and Macrocystis pyrifera were investigated at different latitudes and depths in southeastern Australia. We used multiple performance indicators (photosynthetic characteristics, pigment content, chemical composition, stable isotopes, nucleic acids) to assess the ecophysiology of seaweeds near the northern and southern margins of their range, along a depth gradient (E. radiata only), over a two year period (September 2010 – August 2012).

  • The data is quantitative abundance of fish and megafaunal invertebrates and algal % cover derived from transect based counts at a wide range of locations across Temperate Australia. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. Methods were initially developed for research on temporal changes following protection in Tasmanian MPAs (Maria Is, Tinderbox, Ninepin Point, Governor Island). The data represented by this record was collected in MPA studies and surveys interstate, and was collected from the Port Lincoln district (SA). In many cases the dataset involved temporal replication (year scale).

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    This repository contains data files (netCDF format) related to the model configuration developed and used by Joan Llort between 2011 and 2019. The model is a 1D configuration based on PISCES v1 and the specific routines and namelist are here: https://github.com/jllort/PISCESv1_1D The data in this repository is organised in two groups: - The first group contains the forcing files used to create and idealised representation of Southern Ocean water columns. Forcing files were automatically modified to force PISCES models with different mixed layer depth and iron environments. The files presented here are for a single water column but they can be modified using the python routines in the GitHub link above. - The second group contains the outputs for one of the experiments. We studied the impact of changes in ferricilne, winter mixed layer and summer mixed layer depths over Southern Ocean primary production.

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    A comprehensive and detailed multibeam sonar-based map of the shelf-break region of the Central Flinders Commonwealth Marine Reserve (CMR). It illustrates the extent that several canyon-head incisions are present in this region, and that inset from the shelf-break is a relatively extensive area of cross-shelf reef. Some of the canyon-head incisions are characterised by exposed reef areas, and these are indicated by localised regions of rapid change in depth. The cross-shelf reef is generally very low profile, but characterised by distinct reef ledges where bedding planes in the sedimentary rock types have eroded. These ledges, often between 1-2 m in height, can run for several kilometres as distinct features. The method of data extraction is based on Lucieer (2013). Three are three classes of seafloor map- one from GEOBIA, one from digitisation and one from Probability of Hardness based on Angular Profile Correction. Lucieer, V (2013) NERP broad-scale analysis of multibeam acoustic data from the Flinders Commonwealth Marine Reserve, Prepared for the National Environmental Research Program. Internal report. IMAS, Hobart, TAS [Contract Report]

  • Categories    

    The data is the quantitative abundance of fish derived from underwater visual census methods involving transect counts at rocky reef sites around Tasmania. This data forms part of a larger dataset that also surveyed megafaunal invertebrate abundance and algal cover for the area. The aggregated dataset allows examination of changes in Tasmanian shallow reef floral and faunal communities over a decadal scale - initial surveys were conducted in 1992-1995, and again at the same sites in 2006-2007. There are plans for ongoing surveys. An additional component was added in the latter study - a boat ramp study looking at the proximity of boat ramps and their effects of fishing. We analysed underwater visual census data on fishes and macroinvertebrates (abalone and rock lobsters) at 133 shallow rocky reef sites around Tasmania that ranged from 0.6 - 131 km from the nearest boat ramp. These sites were not all the same as those used for the comparison of 1994 and 2006 reef communities. The subset of 133 sites examined in this component consisted of only those sites that were characterized by the two major algal (kelp) types (laminarian or fucoid dominated). Sites with atypical algal assemblages were omitted from the 196 sites surveyed in 2006. This study aimed to examine reef community data for changes at the community level, changes in species richness and introduced species populations, and changes that may have resulted from ocean warming and fishing. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. The underwater visual census (UVC) methodology used to survey rocky reef communities was designed to maximise detection of (i) changes in population numbers and size-structure (ii) cascading ecosystem effects associated with disturbances such as fishing, (iii) long term change and variability in reef assemblages.

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    Mesozooplankton community composition and structure were examined throughout the D’Entrecasteaux Channel, Huon Estuary and North West Bay, Tasmania, from November 2004 to October 2005. The composition of the mesozooplankton community was typical of inshore, temperate marine habitats, with seasonally higher abundance in summer and autumn and lower numbers in winter and spring. Copepods were the largest contributors to total abundance across all seasons and stations, while cladocerans and appendicularians were proportionally abundant in spring and summer. The faecal pellets of these three main groups, along with those of krill and amphipods, also contributed significantly to material recovered from sediment traps. Meroplanktonic larvae of benthic animals showed short-term peaks in abundance and were often absent from the water column for long periods. Spatially, North West Bay and the Channel had a higher representation of typically marine species, including Calanus australis and Labidocera cervi, while truly estuarine species, such as the copepod Gladioferens pectinatus, were more important in the Huon Estuary.

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    Physical and chemical parameters at five Pacific oyster (Crassostrea gigas) growing areas in Tasmania - Pittwater, Pipeclay Lagoon, Little Swanport, Georges Bay and Simpsons Bay - were measured as part of a study to determine the carrying capacity of the areas for oyster farming. This has provided valuable environmental data for these areas. The hydrodynamic regimes at each area except Simpsons Bay were studied, including high and low water volumes, flushing rates, flow rates and depth contours. Temperature, salinity and concentrations of nitrates, phosphates, silicates and chlorophyll a were measured monthly at several sites in each area. The change in these parameters over different time scales also was examined at two sites in Pittwater and indicated temporal and spatial variability in the environmental parameters measured.

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    Digitised habitat layers for the southern section of the Solitary Islands Marine Park and Solitary Islands Marine Reserve, NSW. Includes reef and unconsolidated seafloor types as interpreted from a series of high resolution bathymetry and backscatter data obtained during swath surveys 2005-2012.