Análise da precisão entre os métodos de interpolação Krigagem Ordinária e Topo to Raster na geração de modelos digitais de elevação

This paper aims to analyze the accuracy of Ordinary Kriging system and Topo to Raster interpolation methods in generation of digital elevation models by using statistical analysis and cross- validation in the watershed of São Bartolomeu stream, located in Viçosa/MG. In order to obtain the digital elevation models (DEMs) were used contour lines, arcs mapped hydrography, limits that define the extent of the study area and the highest points of relief. The processing and analysis of spatial data were performed in ArcGIS software, version 9.3, while the statistical analyses were undertaken in the software Statistica, version 7.0. Two DEMs were generated using Topo to Raster interpolation and one DEM using Ordinary Kriging system interpolation. The MDE standard, used for comparison purposes, was generated using all available input data, while the others were generated only with the highest points of relief. The statistical parameter used in the study was the Root Mean Square Error (RMSE) and cross-validation was performed by comparing visually the contour lines of the DEMs evaluated with a contour lines map. The DEM generated using Ordinary Kriging system interpolator showed the highest index value of RMSE and also presented the greatest topological distortions evidenced in the cross-validation. Thus, the Topo to Raster method was assessed as the best interpolation algorithm, even when all input data that it allows was not used.Pages: 4239-424