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Sampling Theory Using Virtual Forests
I completed the Community Sampling Exercise on the Snyder-Middleswarth Natural Area and received the results from 3 different types of surveys to compare. The systematic-area method produced the shortest estimated sample time of 12 hours and 6 minutes. A quick calculation comparing the estimated density data with the actual data revealed the systematic-area method had a percent error of 28.7%, while random sampling had a percent error of 11.8% and haphazard sampling demonstrated the greatest accuracy rate at 11.6%. The percent error for the Striped Maple was 2.1%, and the White Pine was 14.4% both which are rare species. The common species were Easter Hemlock 6.2% and the Sweet Birch had a percent error of 5.4 %.
The most accurate way to measure both the common species and the rare species was the haphazard method. The accuracy declined with the rare species as some of the rare species were not detected by some of the sample strategies. This leads me to believe 24 sample points did not cover enough ground to accurately represent the rare species. While 24 was adequate to represent the common species, I would recommend increasing the sample points for greater accuracy of the rare species.
