Quality Assessment of the Statistical Land Cover/Use GIS of Slovenia-State'97

D. Šabić, E. H. Lojović, and A. Tretjak

Accurate land cover and land use data on regional level are required for agricultural statistics, national agricultural policy and monitoring environmental changes. In 1995, the first choropleth digital land cover map of Slovenia has been produced from Landsat-TM/93 satellite scanned data by stratification with a minimum mapping unit of 20 hectares of uniform land cover. The obtained digital map confirmed the long suspected but never estimated high increase of the areas under forest and built-up areas on the account of agricultural land. The improvement of the choropleth digital land cover map resulted in a statistical Land Cover GIS of Slovenia-state'93 that revealed the incoherence of the used auxiliary georeferenced databases. The follow up of the work is oriented to an updated statistical Land Cover/ Use GIS of Slovenia-state'97 on a higher level of accuracy using a new set of Landsat-TM/97 data with a 30m x 30m resolution and Spot-Pan/96-97 orthorectified satellite scanned data with a 10 m x 10 m resolution. The quality of the compiled statistical Land Cover/Use GIS of Slovenia-state '97 will be estimated using systematically distributed ground truth segments of size 3,000m x 3,100m. Areal and point methods of quality verification will be analysed regarding the precision of the results, time consumed and costs. The method chosen for the quality estimation of the produced GIS will result in the assignment of the omission and commission error in respect to the land cover category or land use class to each misclassified pixel.