DATASET |
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Title |
Onshore Coastline Habitats of the Recherche Archipelago | ||||||
Custodian |
Department of Conservation and Land Management (CALM) | ||||||
Jurisdiction |
Western Australia | ||||||
DESCRIPTION |
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Abstract |
This dataset
consists of linework detailing the onshore coastline habitats of Southern
Western Australia's Recherche Archipelago and covers approximately 983km
of coastline extending from stokes inlet (121oE) eastward to
Isrealite Bay (124o15'E).
The coastline is delineated into areas of beach, rocky shore, N/A or beach + rocky shore and are further attributed with the direction the habitat is facing, habitat length (metres), beach width (maximum and average in metres). The base coastline linework was provided by DOLA. A source attribute has been added to each line based on the coastline source and/or method used to derive the coastline in any area. Habitats were identified from digital orthophoto mosaics, unrectified hardcopy and digital aerial photography and local knowledge of the physical characteristics of the islands in the area. Beach widths were measured from the digital orthophoto mosaic and aerial photography using ArcViews measure tool and using a scaled adjustable magnifying glass for the hardcopy photography. Habitat facing directions were determined using an avenue script to compute a bearing from North. The dataset was compiled by Ben Lamb in March-June 2002. |
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Search Word(s) |
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Geographic Extent Name(s) |
WA South Coast (WSC) and Eucla (EUC) IMCRA regions | ||||||
DATA CURRENCY |
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Begin Date |
22 February 1991 | ||||||
End Date |
30 March 2000 | ||||||
DATASET STATUS |
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Progress |
In Progress | ||||||
Maintenance & Update Frequency |
As required | ||||||
ACCESS |
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Stored Data Format |
DIGITAL ArcView shapefile, projected to Map Grid of Australia Zone 50 from the Geocentric Datum of Australia 1994 (GDA94). | ||||||
Available Format Type |
DIGITAL ArcView 3.2 shapefile | ||||||
Access Constraint |
Data available
for external use subject to transfer fee and license conditions.
Data is not to be distributed without authorisation from CALM. Contact CALM's database administrator for further details. |
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DATA QUALITY |
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The classification
was undertaken in three stages. Stage 1 was the classification of
the coastline using three digital orthophoto mosaics supplied by DOLA and
the selection of existing photography to be supplied by DOLA in a digital
form. Stage 2 involved the basic georeferencing of the unrectified
digital aerial photography supplied by DOLA and using this as the base
for habitat classifications. Stage 3 was the classification of the
remainder of the coastline from older B&W hardcopy aerial photography
and the classification of offshore islands using Kevin Bancrofts local
knowledge of the physical characteristics of the islands. Details
for all stages are supplied below.
A standard broad scale marine habitat classification system was developed by CALM Marine Conservation Branch (see T:\144-Marine Conservation Branch\Shared Data\Current_papers\Habitat Classification\SMECCS_291101.doc). NOTE: The classification system is being refined on an on-going basis. STAGE 1 (Carried out by Ben Lamb in March 2002)
The digital orthophoto mosaics were the attribute source for 272.7 km of the total 983.1 km of shoreline. STAGE 2 (Carried out by Ben Lamb in March 2002)
The digital aerial photography were the attribute source for 229.4 km of the total 983.1 km of shoreline. STAGE 3 (Carried out by Ben Lamb in May/June 2002)
The hardcopy photography was the attribute source for 51.2 km and evin Bancroft was the attribute source for 359.7 km of the total 983.1 km of shoreline 4. Habitats were further attributed with direction
the habitat is facing. This was determined using an avenue script to calculate
the direction of the line, which was then converted to a facing direction
eg. North, South, East, West, North East, North West, South East
or South West. See 'Attribute Accuracy' below for further
details.
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Positional Accuracy |
Habitat extents
were delineated as accurately as is possible to determine from the available
digital and hardcopy sources. Further Ground-truthing would need to be
undertaken to determine them with greater accuracy.
Accuracy of DOLA's coastline linework is not stated. DOLA has compiled this dataset from a number of sources of best available information including 1:2 000, 1:50 000 and 1:100 000 scale datasets. These source datasets were collected at various levels of positional accuracy, and as such each individual line is as accurate as its source data. The source attribute in the shapefile identifies these sources. |
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Attribute Accuracy |
- Habitat classifications
were determined visually from digital orthophoto mosaics, digital georeferenced
aerial photography and hardcopy aerial photography, and while every effort
has been made to assign these correctly, there may be some errors. The
habitats are accurate as best determined at the time of aerial photography
(Feb 1991 to Mar 2000). Coastlines by their very nature are dynamic and
subject to change due to natural and man-made forces. This is particularly
the case with the movement of sand up and down the coast, and as such beaches
may form and dissappear with the passing of time.Ground-truthing needs
to be undertaken to determine habitats with greater accuracy.
- Beach widths estimated from the digital and hardcopy aerial photography are estimated to be accurate to within 10 metres. Beach widths estimated from the digital orthophotomosaics are estimated to be accurate to within 5 metres. Ground-truthing needs to be undertaken to determine them with greater accuracy. - Habitat directions were determined using an avene
script to calculate the bearing between the first and last points of the
individual polylines. All polylines were split in a uniform direction
so as the polyline direction placed the sea to the right of the line and
the land to the left. Directions were assigned based on the
seaward direction the habitat was facing. The following domain was used
based on the seaward perpendicular of the bearing of the habitat.
- Habitat lengths were determined based on the arc length of the DOLA coastline (after splitting) and calculated automatically using the CALM extension for Arcview3.2. Lengths were rounded to the nearest metre. |
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Logical Consistency |
Attribute
names have been checked and validated for consistency across all shoreline
habitat datasets.
Attribute values have been checked and validated for consistency, and checked for logic in relation to attribute names. All attributes that require values have had values assigned. The shapefile has been compiled carefully to avoid overlaps or duplication of points. |
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Completeness |
The dataset
will be upgraded as priorities, time and resources permit.
Further work needs to be undertaken on ground-truthing. |
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CONTACT INFORMATION |
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Contact Organisation |
Department of Conservation and Land Management, Marine Conservation Branch | ||||||
Contact Position |
Marine GIS Co-ordinator | ||||||
Mail Address 1 |
47 Henry Street | ||||||
Mail Address 2 |
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Suburb or Place or Locality |
Fremantle | ||||||
State or Locality 2 |
WA | ||||||
Country |
Australia | ||||||
Postcode |
6160 | ||||||
Telephone |
08 9336 0109 | ||||||
Facsimile |
08 9430 5408 | ||||||
Electronic Mail Address |
rayl@calm.wa.gov.au | ||||||
METADATA DATE |
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Metadata Date |
5 June 2002 | ||||||
ADDITIONAL METADATA |
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Additional Metadata |
- See accompanying
habitat classification documentation further describing the classification
system(see T:\144-Marine Conservation Branch\Shared Data\Current_papers\Habitat
Classification\SMECCS_291101.doc).
NOTE: This system is still in development. Any feedback would be appreciated. - See DOLA coastline Metadata report for further details on the coastline. |