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Using the virtual forest, I sampled the Snyder-Middleswarth Natural area first systematically, then randomly, then haphazardly. Each of the different sampling strategies had a sample size of 24. The most efficient strategy was area-based systematic sampling, which was estimated to take 12 hours, 6 minutes to sample. Area-based random and haphazard sampling would take 12 hours, 48 minutes and 13 hours, 9 minutes respectively. Percentage error was calculated using the estimated and true values of species density.
Area-based systematic sampling:
Eastern Hemlock: 21.5%
Sweet Birch: 27.7%
Striped Maple: 100%
White Pine: 100%
Area-based random sampling:
Eastern Hemlock: 39.2%
Sweet Birch: 14.9%
Striped Maple: 100%
White Pine: 142.9%
Area-based haphazard sampling:
Eastern Hemlock: 13.2%
Sweet Birch: 19.2%
Striped Maple: 0.09%
White Pine: 100%
Based on these percentage errors, the most accurate sampling method for the Eastern Hemlock was haphazard sampling with only 13.2% error, and random sampling for Sweet Birch with 14.9% error. These are the two most common species of trees in the Snyder-Middleswarth Natural area. The two most rare species, Striped Maple and White Pine, were most accurately sampled using haphazard and systematic/haphazard sampling respectively. Haphazard sampling of Striped Maple resulted in only a 0.09% error and both systematic and haphazard sampling resulted in 100% error as there were no White Pines recorded. In random sampling, White Pines were over-represented and had an error of 142.9%.
Accuracy increased with abundance of a species, as seen by the significantly lower percentage errors in the more common species vs. the rare species. Although each strategy used 24 samples to gather data, White Pine was undetected in both systematic and haphazard sampling, suggesting that the total number of samples was insufficient to truly capture the number of species in the community and their abundance. Of the three strategies, haphazard sampling seemed to most accurately estimate the abundance of each species in the area, as the percentage errors for the common species were relatively low and Striped Maple (rare species) was present.
