Mapping of Poa litorosa and Carex trifida in the Handspike Point area at Macquarie Island 28 March 2003Entry ID: ASAC_1015_MIGPS03
Abstract: Current positional data for Poa litorosa and Carex trifida at Handspike Point area (Macquarie Island) were collected using Global Positioning System (GPS) equipment and standard observational techniques. Different techniques were employed, depending on available expertise and equipment. These techniques are described in detail below. Areas were free from overhead obstructions and therefore ideally ... suited to GPS data collection.
This mapping of the distribution of Poa litorosa and Carex trifida on Macquarie Island together with the mapping of Ranunculus crassipes described by the metadata record with ID ASAC_1015_HIGPS03_04 contributed to the paper:
Bergstrom, D.M., Turner, P.A.M., Scott, J., Copson, G. and Shaw, J. (2006) Restricted plant species on sub-Antarctic Macquarie and Heard Islands. Polar Biology 29 532-539.
Data Set Citation
Dataset Originator/Creator: Bergstrom, D.M. and Turner, P.
Dataset Title: Mapping of Poa litorosa and Carex trifida in the Handspike Point area at Macquarie Island 28 March 2003
Dataset Series Name: CAASM Metadata
Dataset Release Date: 2004-12-09
Dataset Publisher: Australian Antarctic Data CentreOnline Resource: https://data.aad.gov.au/aadc/metadata/metadata_redirect.cfm?md=/AMD...
Start Date: 2003-03-25Stop Date: 2003-03-28
Latitude Resolution: 1 m
Longitude Resolution: 1 m
ISO Topic Category
Quality Current positional data for Poa litorosa and Carex trifida at Handspike Point area, Macquarie Island were collected using Global Positioning System (GPS) equipment and standard observational techniques. Different techniques were employed, depending on available expertise and equipment. These techniques are described in detail below. Areas were free from overhead obstructions and therefore ideally ... suited to GPS data collection.
The collection of positional data for Poa litorosa at Handspike Point, Macquarie Island, was undertaken on the 25th March 2003. Leica SR530 survey grade dual frequency receivers were utilised, operating in both rapid static and kinematic modes.
The receivers are capable of centimetre accuracies over 1-10 km baseline lengths. The survey was divided into two components. Firstly, three new permanent marker locations were surveyed using the rapid static GPS technique. These three permanent markers (metadata) serve as reference points. The GPS reference station for this survey was the Macquarie Island 'MAC1' GPS site which is part of the Australian Regional GPS Network (ARGN) (Twilley and Digney 2001). The datum for the survey was ITRF2000 expressed at epoch 2000.0. The three sites were observed multiple times over durations of 1-5 minutes with the observation rate set to 10 seconds. The second component involved the collection of positional data for individual Poa litorosa colonies. A kinematic GPS observation technique was utilized for this survey, enabling the operator to continually move the roving receiver around the delineation of each colony. The kinematic observations were recorded over a four hour period with several static initialization sessions throughout the survey. The observation rate was 10 seconds. Digital records (photographs and video footage) were also taken in conjunction with positional data, adding a substantial amount of information to mapped data.
Collection of positional data for Carex trifida at Handspike Point, Macquarie Island was undertaken on the 28th March 2003, using a Trimble GeoXT CE series handheld GPS unit. The GeoXT units are mapping grade, single frequency receiver capable of decimetre accuracies over short baselines (less than 5 km). The observation rate was between 30 and 60 seconds. The operator moved the roving receiver around the delineation of each colony. A Trimble ProXR receiver operating as a base station was used. At Macquarie Island it was positioned at the Macquarie Island ANARE Station on the isthmus. The baseline distance between the mobile receivers and field site was less than 5 km. The base station logged data at 5 second intervals.
The Leica SR950 data were post-processed using Leica SKI-Pro software (Leica Geosystems SKI-Pro Software 2002). Phase ambiguity resolution was successful for all data processed resulting in conservative accuracy estimates at the 5 cm and 10 cm level in both the horizontal and vertical components respectively. The GeoXT data were post-processed using Trimble GPS Pathfinder Office (2002). The estimated accuracy for the GeoXT data are at the 25 cm level in both the horizontal and vertical components. Results from both GPS processing suites were imported in Arc View (2002) and projected onto the Australian Map Grid.
The data collection was overseen by Dana Bergstrom of the Australian Antarctic Division and carried out by Paul Boland of DPIWE, Tasmania (Poa litorosa) and Perpetua Turner of the Australian Antarctic Division (Carex trifida).
Access Constraints The rover GPS data for Carex trifida, both uncorrected and differentially corrected data, is available for download from a Related URL.
The metadata record 'Macquarie Island survey, Voyage 6 March 2003' with Entry ID: survey_v6_2003 has links from which the following can be downloaded:
1 The differentially corrected Poa litorosa data in shapefile format; and
2 The base station data used to differentially correct the Carex trifida GPS data.
Use Constraints This data set conforms to the PICCCBY Attribution License
Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=ASAC_101... when using these data.
Data Set Progress
Distribution Media: HTTP
Distribution Size: 274 kb
Distribution Format: Trimble GPS
Phone: +61 3 6232 3209
Fax: +61 3 6232 3351
Email: dana.bergstrom at aad.gov.au
Australian Antarctic Division 203 Channel Highway
Province or State: Tasmania
Postal Code: 7050
Role: TECHNICAL CONTACT
Role: DIF AUTHOR
Phone: +61 3 6232 3163
Fax: +61 3 6232 3351
Email: perpetua.turner at aad.gov.au
203 Channel Highway Australian Antarctic Division
Province or State: Tasmania
Postal Code: 7050
Bergstrom, D.M., Turner, P.A.M., Scott, J., Copson, G. and Shaw, J. (2006), Restricted plant species on sub-Antarctic Macquarie and Heard Islands., Polar Biology, 29, 532-539
Extended Metadata Properties
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Creation and Review Dates
DIF Creation Date: 2004-12-09
Last DIF Revision Date: 2014-12-04