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Land Monitor is a coordinated initiative to
The project involves state and federal agencies and will be completed by the end of 2000. The following flowchart shows the structure of the project. More information about each component of the project can be found by scrolling down this page.
Mapping and monitoring salinity Recent experience has suggested that both government agencies and landholders have grossly underestimated the extent of salt-affected land. Collaborative research work under the National Dryland Salinity Program has developed a range of tools that can be used to map areas of land affected by salinity and monitor changes in the area of salinised land. This work is based on highly sophisticated use of Landsat TM data, digital elevation models and surface water accumulation models coupled with extensive ground truthing. Land Monitor project will systematically monitor salt-affected land over the south west agricultural area of WA. Landsat scenes are available every 16 days from 1987 onwards and can be bought from archived collections. Each scene covers approximately 186 km x 186 km. Digital elevation models (DEMs) can be produced from contour data provided by the Western Australian Land Information Authority. The research work has shown that spring Landsat images are essential for mapping saline land. Ideally, images from three years should be used, to enable an accuracy of greater than 90%, if digital elevation data are also available. Once the saline areas have been identified, the change in area over time can be determined by comparing sequences of images. This provides the only operational method for accurate detection of past trends in the area of salinised land over large areas. Predicting salinity risk areas By combining Landsat scenes, DEMs and surface water accumulation models, areas at risk from future salinisation can be predicted. Accurate, high resolution contour data are required to produce accurate predictions of salinity risk. For this reason, WALIA will produce highly accurate 1-2m contours for the agricultural region. The following is an example of a salinity change map showing predicted risk areas (to be completed). Monitoring remnant vegetation and revegetation Remnant vegetation can be monitored using summer Landsat TM imagery. Mapping and detecting trends in the extent and condition of both natural and revegetated areas have been field tested and proved accurate, within reasonable limits, by a pilot study in the Kent Catchment. Land Monitor will map changes in the extent and condition of remnant vegetation and revegetation since 1987. The following is an example of a map showing changes in the condition of vegetated areas.
Producing highly accurate digital elevation models Accurate, high resolution contour data are available for only a small proportion of the south-west. Land Monitor will produce high quality DEMs using automated techniques. The DEMS will be made available to the general public for other land management purposes. Distributing the data to the community The Land Monitor technical officer will be developing digital and hardcopy information products. Please see the contact page for details. In addition, field trips will be conducted to talk to catchment groups about Land Monitor and completed infromation products. Establishing a baseline for continued monitoring Land Monitor will systematically monitor
and predict salt-affected land, and monitor the condition of both remnant
and revegetated areas, over an 18 million ha area. It will ensure that
an operational structure is in place to allow regular up-dating on a cost
recovery basis. It will also allow timely, accurate information to be used
for environmental auditing purposes as required by a range of State and
Federal imperatives such as the WA State of Environment Report and the
National Collaborative Assessment of Land and Water Resources.
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