High quality information on the distribution, diversity and condition of native vegetation is an essential prerequisite for improving catchment management and ensuring the conservation of these ecosystems. The capture of high quality information about native vegetation across an area the size of the Australian continent has been difficult due to a range of technical, resourcing and administrative issues. A number of vegetation survey and classification techniques have been developed to map the extent of native vegetation at a regional and State/Territory level. As the need arose, these maps were drawn together to create more detailed maps for larger regions including the Australian continent. A good example of this approach is the continental map of vegetation as at 1988 that was published in Volume 6 of the Atlas of Australian Resources. This map is a snapshot of vegetation at a national scale based on interpreting patterns of vegetation observed in 1980s satellite imagery. The continental scale mapping undertaken by the National Land & Water Resources Audit builds on this work. The Audit led the coordination of a National Vegetation Information System (NVIS) that was designed to standardise the mapping of vegetation at a national or broad level. This project was undertaken in close collaboration with State and Territory agencies, who provided the source information. The vegetation information developed through this process was published in the Australian Native Vegetation Assessment 2001 by the Audit. The NVIS, native vegetation report and associated Australian Natural Resource Atlas outline the sources of data used for mapping native vegetation and the present limitations with these datasets. The NVIS framework identifies guidelines to describe structural and floristic characteristics of the vegetation for mapped areas and individual sites; data quality; sources of vegetation information collected in Australia; and vegetation condition. It uses the Australian Vegetation Attributes (Version 5) Information Hierarchy to classify vegetation types into various levels of complexity. The NVIS has been used to identify 23 major vegetation groups and 42 vegetation sub‑groups at a national level. These groups vary significantly in terms of their total area and the sorts of environments they occupy. For example, the tropical rainforests of Queensland’s wet tropics are a stark contrast to the hummock grasslands and saltpans of the arid interior. Both are unique and contain a high degree of endemism. Within these climatic extremes lies a broad range of native vegetation groups with varying structural (height and density) features from tall forests, to varying closed and open shrublands, through to grasslands and forblands, all with their own plant species composition.
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| | Read more about the National Vegetation Information System and its significance for assessing the extent and condition of native vegetation; see http://www.nlwra.gov.au. | | | COST |  | | | TIME |  | | | COMPLEXITY |  | | | | |
The Australian Natural Resources Atlas provides a Map Maker facility that allows managers to access vegetation data and other relevant data for their catchment or region of interest to assess the extent of vegetation types that have been mapped. These datasets can be a useful start to consider the range of vegetation information that is available for a specified area. When using this information, it is important to be aware of the different sources of data that were used to create the continental scale vegetation maps. These varied in the scale they were recorded and the level of accuracy, details of which are recorded in the 2001 Audit report on native vegetation. Atlas information on native vegetation groups can be used to consider vegetation patterns, land use and management options at a State and Territory level, and regional and catchment level in the absence of more detailed vegetation maps. The Australian Capital Territory, for example, has 12 vegetation groups and these have experienced varying degrees of disturbance since European settlement (Figure 4). The largest region of the ACT is covered by the South East Highland bioregion where the clearing of native vegetation has been concentrated and urban infrastructure associated with Canberra is located. Figure 4: Major Vegetation Groups in Australian Capital Territory (circa 1997)
Source: National Land and Water Resources Audit (2001) Major vegetation groups V1.0 (1km), National Vegetation Information System (NVIS),
Commonwealth of Australia (http://audit.ea.gov.au/ANRA/vegetation/vegetation_frame.cfm?region_code=ACT
Continental scale mapping of forests has been underway for about 15 years, with the estimates of forest area regularly updated as the technology for inventory and mapping is refined. The definition of forests agreed to by Australian Governments is broad, and encompasses some woodlands and plantations. For mapping and assessment purposes at the National level, an internationally recognised definition of forests is used: An area, incorporating all living and non-living components, that is dominated by trees having usually a single stem and a mature or potentially mature stand height exceeding two metres and with existing or potential crown cover of overstorey strata about equal to or greater than 20 per cent. This includes Australia’s diverse native forests and plantations, regardless of age. It is also sufficiently broad to encompass areas of trees that are sometimes described as woodlands. The Australian State of the Forest Report 2003 provides up-to-date forest maps at the National and State level. The report uses a framework of criteria and indicators, based on the Montreal Process, which includes the extent of forests. Several of these indicators are interim, as our ability to measure and report on them improves over time. The State of the Forest Report indicates that 164 million hectares (Figure 5), or 21 per cent of Australia’s land area, is classified as forest (land with trees with an actual or potential height greater than 2 metres and 20 per cent crown cover). Of this total, 102.5 million hectares is woodland forest, 45.6 million hectares is open forest, 4.6 million hectares is closed forest (mainly rainforest) and 1.6 million hectares are plantation forests. As part of the national approach to forest assessment, a continental sampling framework is under development to provide a definitive measure of trends in extent, structure, composition, health, status, use and management of all types and tenures of Australia’s forests. While focused on meeting national goals, the framework will also provide a consistent basis upon which monitoring programs to address regional and local goals may be built.
Figure 5: The extent of forest mapped as part of the State of the Forests 2003 report
Source: Bureau of Rural Sciences (2004) Australia’s Forests at a Glance. Commonwealth of Australia, Canberra ACT. p 8
To complement the datasets available through the Australian National Resources Atlas, the Bureau of Rural Sciences has integrated a range of vegetation information to create vegetation type maps for the 56 NRM regions developed in the second phase of the Natural Heritage Trust (see Figure 1 and Figure 6). These maps are available in Integrated Regional Vegetation Information, or can be accessed at the Australian Natural Resource Data Library. There are a number of options available. The tools will allow users to perform searches on metadata records, display relevant metadata records and allow the user to download the associated dataset. The Audit is currently conducting a user review to determine if the Australian Natural Resources Atlas and Data Library are meeting the needs of users and to guide future developments that may enhance their use.
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| | Learn more about the vegetation mapping undertaken by the Bureau of Rural Sciences for the 56 NRM regions in the Australian Natural Resources Data Library. | | | COST | | | | TIME |  | | | COMPLEXITY | | | | | |
The vegetation maps for the NRM regions are designed to provide national overviews at regional scales. The reliability of the vegetation cover information is dependent on the input datasets. The most reliable information occurs where the Land Use Mapping at a Catchment Scale 2003, the National Forest Inventory 2003 and the National Vegetation Information System 2000 datasets all have data coverage. In these regions, the scale of information is around 1:100,000. Otherwise, the scale is approximately 1:1,000,000. Generally, woody and native vegetation are the most reliably represented features, with non-native non-woody vegetation – and particularly grassy cover – being the least reliable. Figure 6:Examples of integrated vegetation maps available for (a) Darwin-Katherine NRM region of the Northern Territory and (b) Northern Agricultural NRM region of Western Australia
Source: Bureau of Rural Sciences (2004) Integrated Vegetation information for NAP and NHTII Regions. (Website) http://data.brs.gov.au/mapserv/
intveg/compiled.html (Accessed July 22)
Other information on the NRM regions, which includes descriptions of vegetation types, can be found by using the Environment Reporting Tool. For major rivers basins and NAP regions, Catchment Condition Online Mapping is also available, which allows users to examine native vegetation information at different scales. The mapping of non-woody vegetation remains a challenge. Composite vegetation maps have been created for several important regions. For example, the CRC for Tropical Savannas has developed a vegetation map-maker and mapping tool (similar to that found at the Audit website) for the tropical savannas spanning the Kimberley of WA through the Gulf of Carpentaria and Cape York in Queensland. This mapping tool can be used to generate vegetation maps for user-specified catchments and regions across northern Australia. Maps of land cover and woody vegetation is available for the Murray-Darling Basin at 25, 100 and 250 metre pixel/resolution size by ordering the Basin-in-a-box package. The Heartlands project Remnant Vegetation Mapping and Setting Priorities for Local Action used the woody non-woody classification for the Murray-Darling Basin as an indicative map of the location and distribution of the remnant woody patches on two sub-catchments. When combined with an environmental stratification, the Murray-Darling mapping data were found to be more consistent than other vegetation mapping available for the two regions. By considering the distribution of vegetation according to different combinations of rainfall, temperature and soil/lithology, the study was able to examine the rarity of native vegetation under different environmental conditions. For example, for both catchments the proportion of the catchment area retaining woody vegetation increases as the mean annual rainfall increases (mean annual rainfall increases as elevation increases). It was recommended that these patterns be used as a basis for prioritisation and community action from the local to sub-catchment scale. An important finding was that priorities for local action can only be established when clear objectives are identified. Similar stratifications of the environment have been used for vegetation mapping as part of the Regional Forest Agreement (RFA) and Comprehensive Regional Assessments (CRA) undertaken in coastal and near-coastal areas of southern and eastern Australia and in Tasmania. These assessments produced a number of vegetation maps, focusing on forested vegetation, as well as models of the distribution of native fauna. For example, the maps produced by the Eden RFA and CRA show modelled pre-1750 vegetation patterns and the distribution of extant vegetation remnants. Mapping from the RFA program has been tested and used in other projects such as the Planning Framework for Natural Ecosystems of the ACT and NSW Southern Tablelands. This framework presents regional scale information on natural ecosystems and biodiversity to provide a decision-making context. Information mainly relates to those species and ecological communities identified as being of conservation importance at the regional scale. The ACT/NSW planning framework is a good working example of the importance of vegetation mapping in regional planning and management, as well as the development of databases that cross jurisdictional boundaries. When vegetation mapping is seen in the context of major catchments, it is clear that many vegetation groups may extend beyond regional and State boundaries. This reminds managers of the need to ensure consistent management of native vegetation across different land tenures and jurisdictions. Grassland ecosystems, particularly in temperate Australia, have been extensively cleared and modified by human activities, with several grassland ecosystems identified as threatened in the Audit terrestrial biodiversity report. Mapping grasslands at a broad scale is an ongoing challenge, as there are difficulties using remotely sensed data to differentiate between different grassland types. In order to address this issue, the Audit developed a rapid and cost-effective method for the identification and delineation of grassland or other herbaceous dominated vegetation communities using satellite images. The study concluded that satellite images were useful in assessing the status of the grasslands in the West Walgett Shire, where the study was conducted, and Mitchell grass grasslands, annual weeds and generic grassland categories were identified and mapped. There are several caveats and recommendations that apply which include the need to collect field data at the same time as images for grassland mapping, to help account for errors associated with inter-seasonal and inter-annual variability. To test the repeatability and robustness of the approach, it was recommended that the technique should be assessed elsewhere in a similar low rainfall cropping area. Overall, remote sensing was seen as supplying useful additional information that could be combined with existing methods to provide a holistic approach. Native grasslands are an important component of the ACT and NSW Southern Tablelands, so as part of the development of the natural ecosystems planning framework, the distribution of grasslands was modelled using data from a grassy ecosystem database. The development of the mapping and classification of grassy ecosystems in this region, and the contribution that remote sensing can make to these goals, is described in detail in Mapping Grassy Ecosystems in South-eastern New South Wales. Once a series of projects mapping grassy ecosystems using remote sensing is finished, the mapping of endangered natural temperate grasslands in south-eastern Australia will almost be complete. Vegetation mapping undertaken as part of the grasslands study, as well as an investigation of The Value of Paddock Trees for Regional Conservation in an Agricultural Landscape, found that smaller areas of woodland could be discerned than those detected in the CRA mapping. In the paddock tree study, it was found that individual and small patches of paddock trees made a major contribution to the representation of certain vegetation types at regional scale. These were woodlands on fertile soils that were preferentially cleared for agriculture, and are largely represented by small patches of trees. As remote sensing technologies improve, the ability to map and monitor individual trees or other small features will increase. State or Territory information sources on native vegetation can be important for regional managers, as they are likely to contain more current information than national datasets and be at a scale appropriate for decision-making. Table 6 summarises the availability of different vegetation data and maps at a State and Territory level. The development of these datasets is a high priority for governments. Details of the availability, coverage, scale and currency of these data can be found at the relevant websites (where available) for each of the responsible government agencies, as well as information on how to acquire this information. When it comes to mapping native vegetation, scale represents one of the most important issues and challenges. The following points give an idea of the size of vegetation patches described by different scales of mapping: - At 1:100,000 scale, the minimum patch size it will map is 100 x 100 m or 1 hectare
- At 1:50,000 scale, the minimum patch size is 50 x 50 m or 0.25 hectare or 2500 m2
- At 1:25,000 scale, the minimum patch size is 25 x 25 m or 625 m2
In addition to mapping the extent of current native vegetation, many States are mapping estimates of the ‘pre-European’ vegetation of a region (which is defined as pre-1750). Such information can be used to estimate the percentage change in vegetation since European settlement, and the percentage of vegetation on public or private land that is formally protected or threatened. For example, in Victoria maps of the pre-European and current vegetation are available at 1:100,000 scale, and new research is aiming to develop similar datasets at 1:25,000 for much of the State. Some parts have been mapped at this scale already, where the native vegetation is particularly fragmented. Vegetation and other natural resource information is available on Victorian Resources Online for each of the regions in the State. Some management agencies have found it difficult to translate information simply between State and National classifications of vegetation. Consequently, several vegetation types used in A Compilation Map of Native Vegetation for NSW are different from the major vegetation groups developed in NVIS. Groups that do correspond are the rainforests, eucalypt forests and heaths. This map, completed in 2002, is the first Statewide map of vegetation produced in NSW. It is intended to provide a resource for State of Environment reporting for the whole of NSW, and a Statewide context for regional planning. Usually it will be appropriate to use the Statewide vegetation map in conjunction with other vegetation data and maps for these purposes. The Statewide vegetation map is insufficiently detailed to function as the primary data source to support regional vegetation planning. The major native vegetation mapping exercise that was producing 1:100,000 vegetation maps for NSW has now been replaced with property level mapping of native vegetation using satellite images. Table 6: Vegetation types and major mapping programs at State and Territory level.
NSW , , NT , , Qld ,
SA , Tas , Vic
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| | Visit the relevant website listed in Table 2.1 for your State or region and investigate what vegetation mapping is available. | | | COST |  | | | TIME | | | | COMPLEXITY | | | | | |
The 1:1,000,000 vegetation map of NSW is reproduced in Ocean Shores to Desert Dunes: The Native Vegetation of New South Wales and the ACT as well as descriptions of 12 broad landscape formations and 99 classes of native vegetation. The vegetation of NSW is currently being reclassified to assess the threat and conservation status of the plant communities in the State. The classification aims to list plant communities at the ‘plant association’ level that takes into account significant canopy and understorey floristic variations. Each plant community is being recorded on an MS Access database with about 60 fields of information. These fields include a list of characteristic species, vegetation structure, common name, scientific name, general description and a photograph, distribution by bioregions, local government area and other regions, soils and substrate, list of threatening processes, comments on condition, fire regimes if known, a IUCN-like (International Union for the Conservation of Nature) threat code using criteria about remaining extent and condition, and a protected area code based on relative extent protected in reserves or secure property agreements. It is anticipated that there will be about 600 to 800 communities listed. About 300 of these will cover the western slopes and plains, which are being assessed first. In Queensland, the vegetation has been mapped as regional ecosystems at a scale of 1:100,000 for most of the State. The Regional Ecosystem Description Database, which is regularly updated and available on the web, lists the status of regional ecosystems. According to its definition, a regional ecosystem is a vegetation community in a bioregion that is consistently associated with a particular combination of geology, landform and soil. The ‘Vegetation Management Status’ is listed in legislation and is based on an assessment of the pre-clearing and remnant extent of the regional ecosystem. The ‘Biodiversity Status’ is based on an assessment of the condition of remnant vegetation in addition to the pre-clearing and remnant extent of a regional ecosystem. Regional ecosystems are listed as endangered, of concern or not of concern, depending on their current extent and condition. The database refers users to where they can access vegetation mapping for regional ecosystems. Background information is available in The Conservation Status of Queensland’s Bioregional Ecosystems. The Statewide Landcover and Trees Study (SLATS) project is another approach to documenting the extent of native vegetation in Queensland. It demonstrates the type of data on land cover change that can be collected and the uses that it can be put towards. The project was founded in 1995 as a major vegetation monitoring initiative to investigate the overall woody vegetation cover and report on the previously unquantified extent of land clearing in Queensland. Some results from this project are presented in the next chapter. In Tasmania, a 1:25,000 vegetation map series has been developed for the State and is available on CD. It will be accessible on-line, with details of these developments and the present vegetation data coverage already available. Major vegetation groups have been mapped for Western Australia and FloraBase can be used to create maps of the distribution of individual plant species of interest (e.g. rare and threatened species). Beginning in 1971, the Biological Surveys of South Australia project has systematically surveyed the flora and fauna of many regions in SA. The project web page provides an extensive list of all of the surveys in the regions/areas that are currently available. Vegetation maps have been completed in some areas based on cattle pastoral areas and large Aboriginal land areas (1:250,000 scale); sheep pastoral country (1:100000 scale) and agricultural districts (1:50,000 scale). The Revegetation Activities, Assessment and Monitoring project commenced in 2002 and in 2004 A National Framework for Assessing the Magnitude and Purpose of Revegetation Activities Across Regional Australia was published looking at private and leasehold land in the intensive land use zone of eastern and southern Australia and the south-west of Western Australia. This work will use information from the NVIS, National Forest Inventory and other sources. The objectives include the development of maps of the extent of revegetation and changes over time. This information will support improved decision-making about government investments in revegetation and ways to support greater community involvement in vegetation management at the catchment level. Land use mapping has become an important tool to understand and improve management at the catchment level. By understanding where different land uses occur, it is possible to assess their existing and potential impacts on native vegetation and the overall health of a catchment or region. This provides the basis to examine different land use options to ensure that the values of native vegetation and other landscape features are conserved wherever possible. A recent report in Science for Decision Makers titled Land Use Mapping at Catchment Scale provides a sound overview of the key issues that regional managers need to consider when undertaking land use mapping. The report describes the latest developments in scientific advice, assessments or tools relating to agriculture and forestry. The key points include: - Land use mapping shows how and where land resources are used. This includes the production of goods (such as crops, timber and manufactures) and services (such as defence, recreation, biodiversity and natural resources protection).
- Land uses have a major impact on Australia’s natural resources through their effects on water, soil, nutrients, plants and animals. There is also a strong link between changing patterns of land use and economic and social conditions, particularly in regional Australia.
- Land use information is critical to those responsible for developing sustainable long-term solutions for our catchments. This includes local government, catchment authorities, emergency services, quarantine and pest management authorities, industry and non-government groups.
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| | Read more about the vegetation and land use mapping work of the Bureau of Rural Sciences to see if detailed land use mapping data is available for your catchment. | | | COST | | | | TIME | | | | COMPLEXITY | | | | | |
Land use mapping is frequently used to investigate issues such as soil loss, salinity, and water quality and to predict likely changes in the condition of native vegetation as different land use practices are undertaken. For example, land use mapping in the north central region of Victoria has been used to help mitigate the impacts of salinity and to improve the protection of remnant patches of native vegetation by improving the management of dryland agriculture. The North Central Catchment Condition Report is a good example of the use of this and other mapping data on native vegetation for meeting the goals in the regional catchment strategy. The Australian Land Use and Management (ALUM) classification was developed to help standardise the collection of digital land use data, and to provide a more consistent and reliable basis to examine and report on land uses across different catchment and landscape settings. One aim of this approach has been to develop a database on land use at the catchment scale that is accurate and covers a consistent set of attributes about land uses and their status. The second edition of Land Use Mapping at Catchment Scale: Principles, Procedures and Definitions is the primary reference for the ALUM Classification and its application. The principles, procedures and classification are based on five primary levels of the degree of disturbance to natural landscapes. The first two levels, ‘conservation and natural environments’ (land used primarily for conservation purposes, based on the maintenance of an essentially natural ecosystem) and ‘relatively natural environments’ (land used mainly for primary production, with limited change to the native vegetation) are the most relevant to native vegetation. To date, the mapping has focused on capturing a snapshot of land use at scales ranging from 1:50,000 to 1:250,000 with validation of mapping undertaken to indicate the confidence that can be placed in the accuracy of the mapping. An overall accuracy greater than 80 per cent meets nationally-agreed standards. Land use and vegetation mapping/planning is undertaken at a number of scales. The appropriate scale will depend on the management objective, but for most catchment and regional scale applications, a scale of at least 1:100,000 is required. While certain information may be applied at a particular scale, it may not always be applied with the same level of confidence at a different scale. It might not be appropriate, for example, to extrapolate a property level technique to a regional level or vice versa. Figure 7 demonstrates the level of detail available at the 1:100,000 scale compared to 1:2,500,000 land use mapping. Section 2.2d demonstrates how the latest remote sensing technologies can be used to develop maps of finer scale. A scale of 1:25,000 is generally considered to be the most appropriate for mapping peri-urban areas and for local government planning purposes, but little land use mapping has been undertaken at this scale at the national level because of the higher costs. Vegetation mapping at this scale to assist communities move towards the sustainable management of Australian landscapes has been done in Victoria and Tasmania. Figure 7: Differences in scale and information contained in the national (1:2,500,000) and catchment scale (1:100,000)
land use maps in the Fitzroy Basin, Queensland. National and catchment scale land use data for part of the Fitzroy shows the difference in levels of information in each type of mapping
Source: Lesslie R, Barson M, Bordas V, Randall L, Ritman K (2003) ‘Science for Decision Makers: Land use mapping at catchment scale: Information for catchment solutions.’ Bureau of Rural Sciences, Canberra ACT. p 3
Biodiversity Action Planning in Your Region: A guide for practitioners, developed in Victoria, illustrates the relationship between some of the different planning and assessment units that are used for managing native vegetation and biodiversity at different scales (Figure 8). Bioregions are represented by the different colours, and are delineated by the boundaries of the North Central Catchment Management Authority boundaries. The ‘zones’, which are indicated by the black lines, are a practical planning unit at a finer scale used in the Bioregional Planning strategies. At a national scale, the Australian Terrestrial Biodiversity Assessment provides overlays of the major river basins on the bioregional framework. These examples demonstrate how some of the different scales being used for natural resource management can be intersected and used for different purposes. |
