Improving Australia's forest area estimate using a Multiple Lines of Evidence approach

This report outlines a new methodology used to determine national forest cover statistics for Australia's National Forest Inventory (NFI). The area of forest cover provides the footprint against which many other indicators of sustainable forest management are reported, including forest type and tenure, forest fragmentation, forest ecosystem services, forest production, forest ecosystem health, and investment in forest management.

ABARES has developed an innovative Multiple Lines of Evidence (MLE) approach to reduce uncertainty in Australia's native forest cover. The approach examines suitable independent forest cover datasets concurrently with an NFI dataset to identify areas of agreement and disagreement between the various datasets. The MLE approach involves 3 stages: first, determining the areas of intersection (agreement) between an NFI dataset and external datasets and deciding an initial level of confidence in the NFI forest cover dataset; second, incorporating reliability scores for each external dataset and refining the level of confidence in the NFI forest cover dataset; and third, validating the forest/non-forest status of areas where low confidence in the NFI forest cover dataset allocation has been deduced. The result is an updated NFI dataset. This report shows the application of the MLE approach using previously published datasets. Key outcomes of the method include more accurate forest cover statistics for Australia, and a capacity to produce reliable forest cover information to meet Australia's national and international reporting requirements. The MLE approach underpins the national forest cover reported in the State of the Forests Report (SOFR) 2013.