Title

Native vegetation extant in Central West Catchments. VIS_ID 3844

Data Quality Statement

Name: Data Quality Statement

Protocol: WWW:DOWNLOAD-1.0-http--download

Description:

Data quality statement for Native vegetation extant in Central West Catchments. VIS_ID 3844

Function: download

Vegetation NativeVegExtent CWCatch VIS 3844

Name: Vegetation NativeVegExtent CWCatch VIS 3844

Protocol: WWW:DOWNLOAD-1.0-http--download

Function: download

Code

780c37da-14e2-4795-a142-ba032f8231d8

Name

ISO 19115

Edition

2016

Code identifying the spatial reference system

4283

Topic category

Title

ANZLIC Search Words

Reference date

2008-05-16

Coordinate reference system

Authority code

urn:ogc:def:cs:EPSG::

Code identifying the coordinate reference system

5711

End position

N/A

Contact info

Contact position

Data Broker

Organisation name

NSW Department of Climate Change, Energy, the Environment and Water

Telephone number

131555

Email address

data.broker@environment.nsw.gov.au

Web address

https://www.nsw.gov.au/departments-and-agencies/dcceew

Responsible party role

pointOfContact

Lineage

Step 1 - Data Audit; A data audit was carried out to identify extant and reconstructed vegetation mapping datasets that covered areas within the Lachlan and Central West CMA administration boundaries. These datasets were vetted for accuracy and precision to assess their suitability and were either rejected or accepted as being suitable for the purpose of this project. Gaps in extant vegetation mapping for the CMA areas were then identified and spatial vegetation datasets (using aerial photo interpretation) were derived for these gaps. ; ; Step 2 - Derivation of Broad Vegetation Groups (BVTs); The accepted and derived datasets were desktop and field assessed by botanists who then derived BVTs that characterised the vegetation across the CMAs. The existing vegetation classes within each dataset were then allocated into one of these BVTs. Datasets were prioritised by accuracy, precision and relevance and merged using this priority order to determine which dataset had precedence where overlap between them occured. This resulted in a vegetation dataset of BVTs that covered existing native vegetation (plus some of the cleared areas).; ; Step 3 - Extrapolation of BVTs into Cleared Areas; An abiotic layer was developed to cover the two CMAs. This abiotic layer was an intersection of an amalgam of soil layers and a land capability/landsystems layer that characterised topography. The theory is that the resulting soils/topography spatial classes would correlate to vegetation classes. The abiotic layer was overlayed with the merged BVT layer and the BVT that had the greatest area within each spatial abiotic unit, was extrapolated into this unit. This resulted in a spatial dataset, whose units are spatially derived from the abiotic layer but whose attributes are those of the BVTs.; ; Step 4 - Filling of Gaps; Small gaps still existed where abiotic units did not overlap with BVTs. Gaps over 250 ha were identified. Where logistically possible these larger gaps were visited in the field and, using remnant vegetation and knowledge of the vegetation landscape relationship of the area, BVTs were allocated to the gaps.; ; Step 5 - Putting the Final Dataset Together; The BVT layer, extrapolated layer and field checked gap layer were merged, with the BVT layer given spatial precedence over the other two layers . Remaining small gaps were detected and filled in using the ArcGIS Spatial Analyst "Nibble" function which basically fills in the gaps using the BVT values of the surrounding area. The result was a reconstructed BVT dataset that gives complete coverage of the Lachlan and Central West CMAs.; ; Step 6; A mask layer was created using the "uncleared and grazed" and "conservation reserve" categories from the CMA Landuse. This mask was then applied to reconstructed layer to give the final extant BVT layer. A further mask of the Central West CMA was then applied..

Limitations on public access

Effective date

2001-01-01

Effective date

2001-01-01

Contact position

Data Broker

Organisation name

NSW Department of Climate Change, Energy, the Environment and Water

Telephone number

131555

Email address

data.broker@environment.nsw.gov.au

Web address

https://www.nsw.gov.au/departments-and-agencies/dcceew

Responsible party role

pointOfContact

Contact position

Data Broker

Organisation name

NSW Department of Climate Change, Energy, the Environment and Water

Telephone number

131555

Email address

data.broker@environment.nsw.gov.au

Web address

https://www.nsw.gov.au/departments-and-agencies/dcceew

Responsible party role

pointOfContact