Systematic Sampling for Estimating Harvest-Induced Changes of a Forest Stand
2009
Peque, Dennis
This study was conducted in Compartment 2012a in Bosinghausen Forest District in Germany covering an area of 5 hectared. Twenty two sampling plots were laid out in the field following systematic sampling design. Results showed that all estimates for all variables (e.g. tree heights, DBH, stem density, basal area and volume) under trees that were marked for cutting have higher relative standard error. This was due to higher dispersion of individual estimates in each plot. On the other hand, the simulation study shows that sampling efficiency can be acheived by increasing the sample size. When more samples are included, the relative standard error becomes low. From this study, it can be concluded that the variability of the estimates were affected by sample size and the variability of individual units in the population or the individual esitmates (in this case, estimates in each plot).
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