The influence of different inventory techniques on the geometrical accuracy of forest geographic data

Abstract

This paper deals with the evaluation of the geometrical accuracy of Lithuanian forests compartments geographical data that has been developed using different forest inventory techniques. Geo-reference background database GDB10LT was used as the standard for comparisons. 2500 control points on clearly identifiable places - crossroads, dikes' intersections, etc. - were selected randomly. The main finding was that the maximal positional root mean square error of clearly identifiable objects in forestry geographic data was 16.47 m (12.37 m and 10.87 m for X and Y coordinates respectively). However, such rather big errors refer to the techniques of GIS database development using paper topographic maps as a background for forest maps and manual digitizing. Enhancement of techniques for GIS database development was found to lead to significant increase in geometrical accuracy of the information.