DIGITALNA ARHIVA ŠUMARSKOG LISTA
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D. Klobučar: PRIMJENA GEOSTATISTIKE U UREĐIVANJU ŠUMAŠumarski list br. 5–6, CXXXIV (2010), 249-259 Uuttera,J., M.Maltamo, S.Kurki, S.Mykrä,vestigations of Forest Ecosystems Using Re1998: Differences in forest structure and land-mote Sensing Imagery. Silva Fennica 39(4): scape patterns between ownership groups in599–617. Central Finland. Boreal Env. Res. 3: 191–200. Osnova gospodarenja za g. j. “Banov Brod”. ISSN 1239-6095. Pravilnik o uređivanju šuma (NN 111/06; NN 141/08). Zawadzki,J., C. J.Cieszewski, M.Zasada, R. C.Lowe,2005:Applying Geostatistics for In- SUMMARY: The possibilities of forest measurements have been significantly improved nowadays, by using georeferenced maps, implementing remote sensing, developing artificial intelligence, using the global positioning system and geographical information system. Moreover, the exact position (x, y) of the measurement (of variables) of the specific location (Z) in the forest allows the monitoring of the information and the analysis of the so called continuous model of spatial variation, as opposed to the discrete model of spatial variation which is assumed to be homogeneous. Ever since geostatistics was introduced to geoscinces (Krige 1951, Matheron 1965), it has been implemented in many areas whose interest lies in analyzing spatial data. Geostatistics is based on the concept of regionalized variable (which means that the value of the variable depends on the sampling area). The goal was research and presentation of using geostatistics in the forest management, with the aim of improving the present approach to using and mapping the forest inventory data for Croatia. The geostatistical analysis was performed on a part of an management unit “Banov Brod”, Pitomača forestry administration, for three structural elements (variables): number of trees (N), basal area (G) and volume (V). The research included the compartments /subcompartments 9a, d, e, 10 a, b (Figure 1), with the total area of 69, 57 ha. In order to determine the anisotropy, semivariogram surface maps of each of the elements were made. The semivariograms were used as a measure of spatial dependence, and experimental and theoretical semivariograms were calculated. The experimental semivariogram for each structural element was calculated after multiple fitting of number and width of lags. The parameters used for Ordinary Kringing interpolation of each of the structural elements were obtained from the theoretical semivariogram model. The interpolation of structural elements was also conducted by using the inverse distance method. The testing of the interpolation model was done by using a numeric cross-validation approach. Furthermore, the usefulness of making a variogram cloud in the spatial structural elements’ analysis was shown. Three programs were used during this project: VARIOWIN 2.21; SURFER 8.0™, and STATISTICA 7.1 ™. Semivariogram surface maps for the three analyzed structural elements did not indicate the presence of anisotropy (Figure 2). As anisotropy was not determined and omnidirectional experimental semivariogram were calculated (Figure 3). All experimental semivariograms can be considered reliable because they contain a great number of pairs of data. What they have in common is the existence of hardly explainable high nugget, that is the difference in the values of close samples or measurement errors, as well as the range, which is bigger than the sampling interval. The omnidirectional experimental semivariogram of the tree volume and basal area (Figures 3a, b) start oscillating very soon, which shows that there is no large range of these two structural elements in any direction. The omnidirectional experimental semivariogram of |