| Summary: | 碩士 === 國立臺灣大學 === 森林環境暨資源學研究所 === 106 === Understanding species composition, size, and spatial distribution of trees are important for forest managers. Recent studies state that forest managers can use stand generators to generate stand structure information. However, method of species assignment of stand generators must be improved. Hershey et al. (1997) introduced indicator kriging to predict spatial distribution of species and suggested this method was a suitable tool for the tree species spatial distribution prediction. In this study, we used indicator kriging to predict spatial presence/absence and ordinary kriging to predict abundance of three tree species in Fushan Forest Dynamics Plot. To study influence of sampling intensity, cell size, and sampling method on prediction accuracy, four levels of sampling intensities (i.e. 5 %, 10 %, 20 %, and 0 % of total number of cells), two different cell sizes (i.e. 5×5 m and 10×10 m), and two different sampling methods (i.e. simple random sampling and systematic sampling) were included in the kriging estimation. Thus, there were a total of 16 combinations of cell size, sampling method and sampling intensity for indicator kriging and for ordinary kriging. Result of this study showed that indicator kriging and ordinary kriging were well behaved in predicting spatial distribution of the three tree species case studies. Sampling intensity significantly influenced the kriging prediction accuracy, by increasing the prediction accuracy as it increases. The influence of cell sizes and sampling methods on indicator kriging and ordinary kriging were smaller than sampling intensity and require further investigation. Forest managers can use these interpolation methods to simulate forest stand for decision making in forest management.
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