Tree Cover Change in Victoria Between 1990 and 1995
Anzlic ID:
ANZVI0803002040
Custodian:
Abstract:
Polygons showing tree cover change as defined by woody vegetation greater than 2 metres in height and with a crown cover (foliar density) greater than 10%. Tree cover is mapped down to a minimum area of quater hectare for change period 1990-1995. Attributes outlining the causes of tree cover change are assigned for areas greater than 1 hectare. This layer was derived from LANDSAT TM digital data.
Search Words:
Biota
,
Imagery base maps earth cover
,
Farming
Publication Date:
02 February 2018
Dataset Status:
Complete for the State of Victoria.
Complete for the State of Victoria.
Progress:
Completed
Access Constraint:
Creative Commons Attribution 4.0 (CC-BY)
(
License Text
)
.
Data Existence:
Metadata Name
Descriptions
Resource Name:
TCH100_9095
Title:
Tree Cover Change in Victoria Between 1990 and 1995
Anzlic ID:
ANZVI0803002040
Custodian:
Owner:
Jurisdiction:
Victoria
Abstract:
Polygons showing tree cover change as defined by woody vegetation greater than 2 metres in height and with a crown cover (foliar density) greater than 10%. Tree cover is mapped down to a minimum area of quater hectare for change period 1990-1995. Attributes outlining the causes of tree cover change are assigned for areas greater than 1 hectare. This layer was derived from LANDSAT TM digital data.
Search Words:
Biota
,
Imagery base maps earth cover
,
Farming
Purpose:
This layer depicts polygons showing tree cover change as defined by woody vegetation greater than 2 metres in height and with a crown cover (foliar density) greater than 10%. Generally tree cover is mapped down to a minimum area of one hectare. For TCH100_9095 a grid filtering technique was applied to remove patches of tree cover less than 0.25 hectare. This process interprets tree cover cells joined at their corners as connected data. Therefore a group of cells connected in this way (e.g a linear roadside strip) that has a total area greater than 0.25 hectrare will remain. When this data is polygonised, those cell may become individual polygons i.e ,creating polygons less than 0.25 hectare. This result is considered beneficial as it retains important linear roadside, streamside and windbreak tree cover which would otherwise be removed by an eliminate process. Areas of tree cover change are mapped down to a minimum area of 1 hectares. This layer was derived from LANDSAT TM digital data.
Geographic Extent Polygon:
Geographic Bounding Box:
Beginning to Ending Date:
1990-01-01 - 1995-12-31
Maintainence and Update Frequency:
Not planned
Stored Data Format:
Available Format(s) Types:
DIGITAL - All major formats available
Positional Accuracy:
Precision: 10m to 100m
Determination: GPS and statistical analysis
Attribute Accuracy:
Year 1990-1993 = A random sampling technique was applied to each map sheet of the 1990 dataset to assess reliability. Reliability varied from 81% to 89% averaging 84.5% across Victoria. The 1993 dataset highlighted errors in the 1990 dataset which were corrected resulting in a much improved accuracy over that initially sampled.
Year 1990-1995 = A random sample of 100 points were generated for each scene to assess the accuracy of the tree cover classification. This was done before any manual editing of the classified classes. Reliability for the classification range from 91% - 97% accurate. The average overall accuracy for the Spectral - Temporal Classification for the 16 scenes which covered Victoria was 93.75%.
Logical Consistency:
Data Source:
Dataset Source: Year 1990-1993 = LANDSAT TM5 satellite images from both summers of 1990 and 1993.
Year 1990-1995 = LANDSAT TM5 satellite images from both summers of 1990 and 1995.
Dataset Originality: Primary
Contact Organisation:
Contact Position:
Address:
Telephone:
Facsimile:
Email Address:
Metadata Date:
2016-05-06
Additional Metadata:
Relationship to other Datasets: Relates to TREE100.
Current Design Issues: The layer was created to give an accurate assessment of tree cover extent for the state of Victoria and to provide a baseline dataset for further projects based around tree cover. This layer shows only the change in tree cover.
Related Documents: None
Year 1990-1993
A report is to be released: Tree Cover Change in Victoria 1869 to 1993 An outline of Methods for Mapping and Monitoring. Adam Gilbee
Year 1990-1995
A report is to be released: Remote Sensing of Agriculture Land Cover Change for Australia;
Victorian project report 1997. Isabel Coppa, Rick Frisina, Adam Choma.