Here, there, or everywhere? An accuracy assessment and the influence of ecoregions in the spatial distribution of errors in a vegetation land cover mapping assessment of Victoria, Australia

Forests provide many benefits to individuals, societies as well as the biosphere in general. Forest loss can lead to increased greenhouse gases, an increase in salinity, decreased biodiversity and the extinction of species. As part of the sustainable management of Victoria's forests the Department of Sustainability and the Environment (DSE) has created the 2008 land cover baseline via the aerial photographic interpretation (API) of 790 2x2 km digital high resolution colour aerial photographs, so that information regarding the state, extent and condition of Victoria's public land forests can be monitored. This study conducted an accuracy assessment of the resultant API maps, with respect to their ability to classify forested/ non-forested land cover, forest height, and forest vegetation type. This assessment was made by comparing the API derived maps to 125 field plots. An aspect of the spatial distribution of API errors was investigated by stratifying the data set into three Victorian ecoregions. Results indicate that the API accurately classified forest/ non-forest land cover and vegetation type. The classification of height was less precise, with the Mediterranean forest, woodland and scrub ecoregion obtaining more successful results. Despite these errors, the API was successful at identifying forest areas and is a valuable tool in the monitoring and reporting of forests across Victoria.