Australia - Present Major Vegetation Subgroups - NVIS Version 4.1 (Albers 100m analysis product)

## **Abstract** 

This dataset and its metadata statement were supplied to the Bioregional Assessment Programme by a third party and are presented here as originally supplied. 



This raster dataset 'NVIS4_1_AUST_MVS_EXT_ALB' provides the latest summary information (November 2012) on Australia's present (extant) native vegetation, which has been classified into Major Vegetation Subgroups. It is in Albers Equal Area projection with a 100 m x 100 m (1 Ha) cell size. A comparable Estimated Pre-1750 (pre-European, pre-clearing) raster dataset is available: - NVIS4_1_AUST_MVS_PRE_ALB. State and Territory vegetation mapping agencies supplied a new version of the National Vegetation Information System (NVIS) in 2009-2011. Some agencies did not supply new data for this version but approved re-use of Version 3.1 data. Summaries were derived from the best available data in the NVIS extant theme as at June 2012. This product is derived from a compilation of data collected at different scales on different dates by different organisations. Please refer to the separate key map showing scales of the input datasets. Gaps in the NVIS database were filled by non-NVIS data, notably parts of South Australia and small areas of New South Wales such as the Curlewis area. The data represent on-ground dates of up to 2006 in Queensland, 2001 to 2005 in South Australia (depending on the region) and 2004/5 in other jurisdictions, except NSW. NVIS data was partially updated in NSW with 2001-09 data, with extensive areas of 1997 data remaining from the earlier version of NVIS. Eighty-five (85) Major Vegetation Subgroups identified in v4.1 to summarise the type and distribution of Australia's native vegetation. The classification contains an emphasis on the structural and floristic composition of the dominant stratum (as with Major Vegetation Groups), but with additional types identified according to typical shrub or ground layers occurring with a dominant tree or shrub stratum. In a mapping sense, the subgroups reflect the dominant vegetation occurring in a map unit from a mix of several vegetation types. Less-dominant vegetation groups which are also present in the map unit are not shown. For example, the dominant vegetation in an area may be mapped as dominated by eucalypt open forest with a shrubby understorey, although it contains pockets of rainforest, shrubland and grassland vegetation as subdominants. A number of other non-vegetation and non-native vegetation land cover types are also represented as Major Vegetation Subgroups. These are provided for cartographic purposes, but should not be used for analyses. The (related) Major Vegetation Groups represent the dominant vegetation groups in the dominant stratum and are available as separate raster datasets: - NVIS4_1_AUST_MVG_EXT_ALB - NVIS4_1_AUST_MVG_PRE_ALB For further background and other NVIS products, please see the links on http://www.environment.gov.au/erin/nvis/index.html.



The current NVIS data products are available from http://www.environment.gov.au/land/native-vegetation/national-vegetation-information-system.

## **Dataset History** 

The input vegetation data were provided from over 100 individual projects representing the majority of Australia's regional vegetation mapping over the last 50 years. State and Territory custodians translated the vegetation descriptions from these datasets into a common attribute framework, the National Vegetation Information System (ESCAVI, 2003). Scales of input mapping ranged from 1:25,000 to 1:5,000,000. These were combined into an Australia-wide set of vector data. Non-terrestrial areas were mostly removed by the State and Territory custodians before supplying the data to the Environmental Resources Information Network (ERIN), Department of Sustainability Environment Water Population and Communities (DSEWPaC).



Each NVIS vegetation description was written to the NVIS XML format file by the custodian, transferred to ERIN and loaded into the NVIS database at ERIN. A considerable number of quality checks were performed automatically by this system to ensure conformity to the NVIS attribute standards (ESCAVI, 2003) and consistency between levels of the NVIS Information Hierarchy within each description. Descriptions for non-vegetation and non-native vegetation mapping codes were transferred via CSV files.



The NVIS vector (polygon) data for Australia comprised a series of jig-saw pieces, each up to approx 500,000 polygons - the maximum tractable size for routine geoprocesssing. The spatial data was processed to conform to the NVIS spatial format (ESCAVI, 2003; other papers). Spatial processing and attribute additions were done mostly in ESRI File Geodatabases. Topology and minor geometric corrections were also performed at this stage. These datasets were then loaded into ESRI Spatial Database Engine as per the ERIN standard. NVIS attributes were then populated using database tables provided by custodians, mostly using PL/SQL Developer or in ArcGIS using the field calculator (where simple).



Each spatial dataset was joined to and checked against a lookup table for the relevant State/Territory to ensure that all mapping codes in the dominant vegetation type of each polygon (NVISDSC1) had a valid lookup description, including an allocated MVS. Minor vegetation components of each map unit (NVISDSC2-6) were not checked, but could be considered mostly complete. 



Each NVIS vegetation description was allocated to a Major Vegetation Subgroup (MVS) by manual interpretation at ERIN and in consultation with data custodians. 12 new MVSs were created for version 4.1 to better represent open woodland formations, more understorey types and forests (in the NT) with no further data available. Also, a number of MVSs were redefined after creation of the new groups to give a clearer and precise description of the Subgroup. For example,  MVS 9 - 'Eucalyptus woodlands with a grassy understorey' became 'Eucalyptus woodlands with a tussock grass understorey' to distinguish it from MVS10 - 'Eucalyptus woodlands with a hummock grass understorey'.  NVIS vegetation descriptions were reallocated into these classes, if appropriate:

- Warm Temperate Rainforest

- Eucalyptus woodlands with a hummock grass understorey

- Acacia (+/- low) open woodlands and sparse shrublands with a shrubby understorey

- Mulga (Acacia aneura) open woodlands and sparse shrublands +/- tussock grass

- Eucalyptus woodlands with a chenopod or samphire understorey

- Open mallee woodlands and sparse mallee shrublands with a hummock grass understorey

- Open mallee woodlands and sparse mallee shrublands with a tussock grass understorey

- Open mallee woodlands and sparse mallee shrublands with an open shrubby understorey

- Open mallee woodlands and sparse mallee shrublands with a dense shrubby understorey

- Callitris open woodlands

- Casuarina and Allocasuarina open woodlands with a tussock grass understorey

- Casuarina and Allocasuarina open woodlands with a hummock grass understorey

- Casuarina and Allocasuarina open woodlands with a chenopod shrub understorey

- Casuarina and Allocasuarina open woodlands with a shrubby understorey

- Melaleuca open woodlands

- Other Open Woodlands

- Other sparse shrublands and sparse heathlands

- Unclassified Forest



Data values defined as cleared or non-native by data custodians were attributed specific MVS values such as 42 - naturally bare, sand, rock, claypan, mudflat; 43 - salt lakes and lagoons; 44 - freshwater lakes and dams; 46 - seas & estuaries, 90, 91, 92 & 93 - Regrowth Subgroups; 98 - Cleared, non native, buildings; and 99 - Unknown.



As part of the process to fill gaps in NVIS, the descriptive data from non-NVIS sources was also stored in the NVIS database, but with blank vegetation descriptions. In general, the gap-fill data comprised (a) fine scale (1:250K or better) State/Territory vegetation maps for which NVIS descriptions were unavailable and (b) coarse-scale (1:1M) maps from Commonwealth and other sources. MVGs were then allocated to each description from the available desciptions in accompanying publications and other sources. 



Parts of New South Wales, South Australia, QLD and the ACT had extensive areas of vector "NoData", thus appearing as an inland sea. The No Data areas were dealt with differently by state. In the ACT and SA, the vector data was 'gap-filled' with polygons and attributed using satellite imagery as a guide prior to rasterising. Most of these areas comprised a mixture of MVS 43, 44 & 46 (water) and 98 (cleared), and in some case 99 (Unknown). The NSW & QLD 'No Data' areas were filled later in the workflow using a raster mask to fill the 'holes'. These areas were attributed with MVS 43, 44, & 97 (water & unclassified veg), MVS 98 (cleared); or MVS 99 Unknown/no data, where these areas were a mixture of unknown proportions.



Each spatial dataset with joined lookup table (including MVS_NUMBER linked to NVISDSC1) was exported to a File Geodatabase as a feature class. These were reprojected into Albers Equal Area projection (Central_Meridian: 132.000000, Standard_Parallel_1: -18.000000, Standard_Parallel_2: -36.000000, Linear Unit: Meter (1.000000), Datum GDA94, other parameters 0).



Each feature class was then rasterised to a 100m raster with extents to a multiple of 1000 m, to ensure alignment. In some instances, areas of 'NoData' had to be modelled in raster. For example, in NSW where non-native areas (cleared, water bodies etc) have not been mapped. The rasters were then merged into a 'state wide' raster. State rasters were then merged into this 'Australia wide' raster dataset.



November 2012 Corrections

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Closer inspection of the original 4.1 MVS Extant raster dataset highlighted some issues with the raster creation process which meant that raster pixels in some areas did not align as intended. These were corrected, and the new properly aligned rasters released in November 2012. 



MVS Legend

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The MVS legend is a complex structure given the number of classes involved. The shadeset in the accompanying layer file is regarded as an interim solution, whilst the order of classes needs to be re-organised manually to conform with the SORT_ORDER field as provided in the Raster VAT.

## **Dataset Citation** 

Department of the Environment (2012) Australia - Present Major Vegetation Subgroups - NVIS Version 4.1 (Albers 100m analysis product). Bioregional Assessment Source Dataset. Viewed 14 June 2018, http://data.bioregionalassessments.gov.au/dataset/5d09d8f2-4471-4503-9de5-1e52009dd7c6.

Tags: Australia, Cooper subregion, Gippsland Basin bioregion, Gloucester subregion, Hunter subregion, Sydney Basin bioregion, biota
Organization: Bioregional Assessment Program