Community level impacts of Maoricolpus roseus on the function of native soft sediment assemblages
The impact of the introduced New Zealand screw shell, Maoricolpus roseus, were assessed using a cageing experiment in SE Tasmania (Bligh Point, D'Entrecasteaux Channel). Three treatments consisted of different substratum type (live, dead and empty shells, and dead shells with 50% occupancy by hermit crabs); which were crossed with 2 levels of screwshell density (high and low). Treatment groups were artificially maintained for 20 months before metabolic chambers were used to quantify the community metabolism of different treatment groups.
Simple
Identification info
- Date (Creation)
- 2008-09-05T10:27:00
Principal investigator
Principal investigator
Principal investigator
- Purpose
- To assess community-level impacts of an introduced species on native soft-sediment assemblages in SE Tasmania.
- Credit
- School of Zoology, University of Tasmania
- Credit
- Natural Heritage Trust (NHT) Grant from DEH
- Status
- Completed
Principal investigator
Principal investigator
- Spatial representation type
- Text, table
- Topic category
-
- Biota
Extent
Temporal extent
- Time period
- 2005-12-01T16:04:00 2007-08-31T16:04:00
Vertical element
- Maximum value
- 12
- Maintenance and update frequency
- Not planned
Resource format
- Title
- Excel
- Date
- Edition
- 2003
- Global Change Master Directory Earth Science Keywords v.5.3.8
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- Biosphere | Aquatic Habitat | Benthic Habitat
- Oceans | Marine Biology | Marine Invertebrates
- Biosphere | Ecological Dynamics | Community Structure
- Biosphere | Ecological Dynamics | Competition
- CAAB - Codes for Australian Aquatic Biota v2
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- 24 079001
- Maoricolpus roseus
- Australian and New Zealand Standard Research Classification (ANZSRC): Fields of Research
- Keywords (Theme)
-
- Epifauna density
- Biomass
- Primary production
- Community respiration
- Net oxygen flux
Resource constraints
- Classification
- Unclassified
Resource constraints
- Use limitation
- The data described in this record are the intellectual property of A. Reid.
Resource constraints
- Linkage
-
http://i.creativecommons.org/l/by/2.5/au/88x31.png
License Graphic
- Title
- Creative Commons Attribution 2.5 Australia License
- Website
-
http://creativecommons.org/licenses/by/2.5/au/
License Text
- Other constraints
- The citation in a list of references is: citation author name/s (year metadata published), metadata title. Citation author organisation/s. File identifier and Data accessed at (add http link).
- Other constraints
- This data is yet to be published, please contact the researcher for access to the data.
Associated resource
- Title
- Impacts of the introduced New Zealand screwshell Maoricolpus roseus
- Date (Creation)
- 2011-09-02T00:00:00
- Language
- English
- Character encoding
- UTF8
- Environment description
- Excel spreadsheet (xls)
- Supplemental Information
- Reid, A.P. 2010. Impact of the Introduced New Zealand Screwshell Maoricolpus roseus on Soft-sediment Assemblages in Southeast Tasmania. University of Tasmania PhD thesis
Content Information
- Content type
- Physical measurement
- Name
-
Epifauna density
- Name
- Number per 0.25m2
- Name
-
Biomass
- Name
- Grams
- Name
-
Primary production
- Name
- mmolO2/0.25m2/day
- Name
-
Community respiration
- Name
- mmolO2/0.25m2/day
- Name
-
Net oxygen flux
- Name
- mmolO2/0.25m2/day
Distribution Information
- Distribution format
-
-
Excel
-
Excel
Distributor
Resource lineage
- Statement
- Experimental design Treatments included 3 levels of substratum type (live screwshells, dead and empty screwshells, and dead screwshells with 50% occupancy by hermit crabs) crossed with 2 levels of screwshell density (200m-2 and 500m-2). There were 4 replicates of each treatment group, and the experiment was maintained over 20 months. After this time, metabolic chambers (described below) were deployed over each experimental plot for 22 hours (encompassing both a day and night time period). Treatment cages comprised 0.75m x 0.75m x 90mm PVC frames. Control groups included cages over unmanipulated areas without screwshells and unmanipulated areas without screwshells or cages. After chamber incubations were complete, 3 x 80 mm sediment cores (30 mm diameter) were extracted from each plot. From these, the biomass of microphytobenthos (MPB) was calculated. Cores were stored at -80 C, MPB biomass was calculated using a 90% acetone extraction on the upper 5mm of each core. In plots containing screwshells, random sub-samples were collected and processed for epiphyte biomass using the acetone extraction method. Epifauna attached to screwshells were counted, removed and stored in 70% alcohol. After cores and shells were removed from each plot, plots were suction-sampled to 100mm depth using a custom made air lift. Samples were fixed in 5% formaldehyde solution with Rose Bengal stain and stored for identification. In the lab samples were sieved over 4mm, 2mm and 1mm mesh sizes. All infauna was removed from the 4mm portion, but the 2mm and 1mm samples were split using a Jones-style riffle splitter into quarters, and 2 of these were sampled. All infauna were removed and stored in 70% alcohol, counted and weighed (wet) using a balance accurate to 0.01g to quantify biomass. Epifaunal biomass were estimated.
- Hierarchy level
- Dataset
Resource lineage
- Statement
- Metabolism chambers - design The chambers consisted of a transparent polyvinyl chloride (PVC) cylinder, 300 mm diameter x 200 mm high. One end was sealed (PVC), and the other open and chamfered. A magnetic stirrer attached to the chamber roof controlled circulation. The stirrer was driven by a 9V DC motor, rotated at ca. 8 rpm. Gauges on the chamber sides allowed depth of insertion into the sediment and therefore volume of the chamber to be calculated. An optic fibre dissolved oxygen (DO) probe (Aanderaa oxygen optode 4130) was inserted through the chamber roof and recorded DO concentration and water temperature (degrees) every 10 minutes onto a data logger which was mounted separate to the chamber in a translucent submersible housing (Icolite). The data logger was a Tattletale TFX 1-11.v2 and associated prototype board (Onset computer corp.). Separate data loggers enabled chambers to be controlled separately and data to be stored separately. Photosynthetically Active Radiation (PAR) was measured and logged by 2 independent underwater sensors (Li-cor LI-192SA) mounted on the outer surface of the chamber. Activation of the PAR sensors was controlled by the data logger. For the 10 minute interval between DO readings, the PAR sensor pulsed every 2 minutes and the averages of these 5x2 minute reading was stored on the logger.
- Hierarchy level
- Collection hardware
Resource lineage
- Statement
- Validation of chamber accuracy and use When using a closed system chamber to quantify community metabolism, problems can arise if condition within the chamber change (e.g. if oxygen concentration becomes excessively low). To assess if communities responded to reductions in oxygen concentration, 2 paired chambers were deployed in the same randomly selected treatment plot - one with a 12 V DC bilge pump enabling the chamber to be flushed at selected intervals, and the second a standard set-up (no pump). Paired chambers were deployed in 10 randomly selected treatment plots and the flux estimates calculated from the flushed chambers were compared to those from the unflushed chambers. The absence of non-linear oxygen fluxes, coupled with the absence of differences between the oxygen flux obtained from both chambers on the same community, was a clear indication that the community within either chamber did not respond adversely to the changing oxygen concentration within the chambers.
- Hierarchy level
- Attribute
Metadata
- Metadata identifier
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302aaf80-7d37-11dd-a8f2-00188b4c0af8
- Language
- English
- Character encoding
- UTF8
Point of contact
Type of resource
- Resource scope
- Dataset
- Metadata linkage
-
https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/302aaf80-7d37-11dd-a8f2-00188b4c0af8
Point of truth URL of this metadata record
- Date info (Creation)
- 2015-07-21T14:53:39
- Date info (Revision)
- 2015-07-21T14:53:39
Metadata standard
- Title
- ISO 19115-3:2018