Forest attributes and spatial autocorrelation and interpolation: effects of alternative sampling schemata in the boreal forest

It was not possible to estimate forest volume surfaces having high local precision using samples from three different relatively dense sampling schemata and two spatial interpolation techniques. At best, volume estimates for a given location from area-stealing interpolation or kriging were no more precise than ±80% with 95% confidence even for a forest sample having an intensity of 16%. This precision is only a slight improvement over using the mean as an estimate for each sample location. Although areas of high volume do tend to cluster, i.e. are positively spatially autocorrelated, the forest did not behave as a continuous surface relative even to the densest sampling schema. This suggests that only conducting an a priori assessment of spatial autocorrelation to determine interpolability may be misleading.