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For the Sampling Theory Using Virtual Forests tutorial, the Snyder-Middleswarth Natural Area was selected. I used area-based methods for Systematic Sampling, Random Sampling and Haphazard Sampling.
On review of the three methods, the estimated time for Systematic Sampling was 12 hours, 36 minutes. For Random Sampling, the estimated time was 13 hours, 40 minutes and for Haphazard Sampling the estimated time was 12 hours, 22 minutes. Haphazard sampling was estimated to be the most time efficient, followed by Systematic and Random.
For the Systematic Sampling, the percentage error for the two most common species were 17.4% and 38.7% respectively, with the percentage error for the two least common species at 100% and 60% respectively. For the Random Sampling, the percentage error for the two most common species were 20.3% and 16.7% respectively, with the percentage error for the two least common species at 100% and 78% respectively. For the Haphazard Sampling, the percentage error for the two most common species were 3.3% and 4.2% respectively, with the percentage error for the two least common species at 100% and 52.6% respectively. A percentage error of 100% indicated there were no trees of that species identified during the sampling.
The lowest percentage error was consistently the most common species, with the largest percentage error consistently the two least common species. Based on this, it could be assumed that the accuracy increases with an increase in abundance. It could also be assumed that the accuracy decreases with a decrease in abundance. On average, Haphazard Sampling had the lowest percentage error (40%), followed by Random Sampling (53%), then Systematic Sampling (54%).
Overall, the Haphazard Sampling was estimated to be the most time efficient and had the lowest percentage error.
