Metadata : NVIS Version 4.1- National Vegetation Information System, Northern Territory 2012

Index:


Metadata Details:

Name:AS/NZS ISO 19115 Geographic Information - Metadata, ANZLIC Metadata Profile

Version:1.0

Date Metadata Extracted:2024-12-07

Date Metadata Last Updated:2012-02-02

Current URL (HTML format) : http://www.ntlis.nt.gov.au/metadata/export_data?type=html&metadata_id=B75510B92F680755E040CD9B2144596C

Current URL (XML format) : http://www.ntlis.nt.gov.au/metadata/export_data?type=xml&metadata_id=B75510B92F680755E040CD9B2144596C


Citation

ANZLIC Identifier:B75510B92F680755E040CD9B2144596C

Title: NVIS Version 4.1- National Vegetation Information System, Northern Territory 2012

Citation Date:2012-01-01

Date Type:revision

Custodian:Department of Environment, Parks and Water Security


Description

Abstract:

An amalgamation of the NVIS version 3.1 and Northern Territory Forest Mapping, NORFOR. Data set was developed in order to align the NVISver3 data set (DEWHA) and the forest data sets sent to the National Forest Inventory (AFFA).
For information on each particular map dataset see the following records on the NT Spatial data directory.

2DBCB771207006B6E040CD9B0F274EFE NVIS - National Vegetation Information System, NT Data Compilation - Land & Vegetation Branch / Natural Systems Division

2DBCB771213506B6E040CD9B0F274EFE - Norfor - Mapping the Forest Cover of the Northern Territory - 2001

or ANZLIC numbers on ASSD

NVIS - National Vegetation Information System, NT Data Compilation - Land & Vegetation Branch / Natural Systems Division ANZNT0001001047

Norfor - Mapping the Forest Cover of the Northern Territory - 2001 ANZNT0903000039

For each survey a 'PRE1750' and an 'EXTANT" coverage was produced. The 'PRE1750' coverage or 'pre-clearing' coverage represents, in theory, the vegetation that existed in that particular survey region before the arrival of the white man. In all the surveys attributed to NVIS standard in the NT, this 'PRE1750' coverage was
taken to be the original survey coverage produced. The 'EXTANT' coverage or present day coverage represents, in theory, the present day (circa 2004) vegetation coverage. This was produced by updating the 'PRE1750' coverage with a coverage containing cleared or modified vegetation, the so called 'clearing' coverage (see comments).

NOTE: due to text limits LINEAGE continues in completeness section

ANZLIC Search Words:

Spatial Domain:

Bounding Coordinates:


Dataset Status

Dataset ID:

Language:English

Character Set: Latin 1

Progress:completed

Maintenance and Update Frequency:asNeeded

Data Currency Start Date:1998-01-01

Data Currency End Date:2012-01-01

Access Constraint:

Download the spatial data package (contains spatial data, maps and reports) via data.nt.gov.au/

You are licensed to use the DENR geospatial products on the terms and conditions set out in: Creative Commons Attribution 4.0 International Public License (CC BY 4.0) at: creativecommons.org/licenses/by/4.0/legalcode

If you do not agree to the terms and conditions you must not use the geospatial products.

You are free to copy, communicate and adapt the licensed material, provided that you abide by the licence terms (including Attribution) and attribute the licensed material using the statement:

Supplied by the Department of Environment and Natural Resources. Copyright Northern Territory Government.


Data Quality

Lineage:The NVIS ver 4.1 refers to the NVIS-NFI integrated data set. This was produced a number of years ago by combining the NORFOR FPC data into the current NVIS2005ver3 Pre-European data set. This coverage affects the northern part of the NT. This coverage was produced in response to the need for the NVIS forest mapping data set (at level 3) and the NFI forest data set to provide the same forest area values. It was meant as an interim data set to address this rather than a complete update for NVIS. the original NVIS dataset was split at 18 degrees south into a north and south section. The NORFOR data was combined with the north section. The north and south sections were then recombined (see below).
Due to software limits the north coverage needed to be tiled (13 sections) and re -combined. During the re-combining process some spatial line work errors were introduced (very narrow linear strips along some join lines). These remain in the current dataset.

Pre European Data set: Brief processing history
The original Pre-European Arc/Info coverage was converted to a shape-file and updated with new map unit identification attribution (NEWMAP,NVIS_NFI_MAPID).
This was then converted back to a coverage. As software limits where encountered the shape-file needed to be split in two, then converted back to a coverage (aml), APPENDED together and DISSOLVED. A number of small slither polygons were removed from final coverage.

Integrating the NVIS and NFI data sets has resulted in the production of a large number of new vegetation descriptions that differ only at the structural formation level (canopy cover values). This however necessitates a number of attributes to be changed. An automated process to re attribute tables was necessary and this was done by DEWHA..

Creating new veg descriptions was problematic for the existing data base as well as for SPATIAL_DATA table and mosaics. A rule set was devised to overcome this.
LINEAGE CONTINUED IN COMPLETENESS SECTION

Positional Accuracy:As per original coverages at scale. This dataset has been derived from data at different scales varying from 1:100,00 scale to 1:1,000,000 scale. The summation of errors from this dataset results in data with a standard deviation defined by scale used as +/-200m for well-defined points. Dataset metadata contained in attribute information on NVIS coverages (as per the NVIS Vegetation Attribute Framework Version 6.0).

Attribute Accuracy:As per original coverages. All coverage attributes as per the NVIS vegetation attribute framework Version 5.0 (NLWRA 2000). These were determined from original survey reports (eg transcribed from information contained in survey report). Each polygon was recoded to the NVIS polygon coding system (MU_ID attribute). The SOURCE_CODE attribute in the NVIS coverages contains the map unit code from the original survey.

Logical Consistency:Dataset topological consistency has been system checked and all classified polygons are closed, nodes are formed at intersections, there is one label per polygon and all polygons have been classified for MU_ID (map unit_id). The MU_ID provides the link between the polygon coverages and attribute database. Polygons boundaries were altered for some surveys from original coverages.

Completeness:Judged complete at this stage - spatial and attribute verification of the dataset has been performed.
LINEAGE CONTINUED
Rules for New map-units:
(* NEW MAPUNIT_IDS/NEW VEG-IDs get the same VEGDSC2-VGDESC5 and proportions as original map-units if they are mosaics
* If pure polygons not a real problem for the SPATIAL_DATA table only NEW MAPUNIT_IDS/NEW VEG-IDs need be created
* If new MAPUNIT_ID/VEG_ID is closed forest then the new unit becomes a pure polygon even though the original one may have been a mosaic )

Present Vegetation data set: Brief processing history -

The new Pre-European shape file data set was updated with the Native Vegetation Extent 2004 base-line data set (recently provided to NLWRA). This was then reconverted into a coverage in a similar manner as stated previously. All cleared land (NATIVE VEG EXTENT cut in) becomes non native/infrastructure/cleared etc. These polygons were not attribute with current land-use (i.e. just one label for all of them).


Contacts

NameOrganisationPositionRolePhoneFaxEmail
Data Requests OfficerDepartment of Environment, Parks and Water SecurityGeospatial Services Branch (on behalf of department)distributordatarequests.depws@nt.gov.au

Data Dictionary

No data dictionary defined for this dataset

Supplementary Information

The 'clearing' coverage was produced from various sources and is by no means comprehensive. Only large areas of clearing have have been delineated. It does not represent all the cleared or modified areas in the NT, particularly smaller areas. It also does not contain any information as to the present status of the cleared areas. They will be blanked out and listed as 'cleared'. The 'cleared' polygons could be revegetated, contain crops, horticulture, urban areas, railroads etc. The municipal areas of Katherine and Alice Springs were excised out entirely and contain remnant patches within their boundaries. Some pastoral properties also have small areas of clearing, which have not been incorporated in the 'clearing' coverage. Also no up to-date fine scale mapping of vegetation modification or clearing in the NT is available at present (year 2004).

This record maintained using the NTLIS Metadata Tool