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The three sampling strategies I used in the virtual forest tutorial are Systematic, Random and Haphazard techniques.
I used area based methods to compare among the sample placement strategies. Please find here below, the tables demonstrating the collected sampling data collected on Snyder-Middleswarth Natural Area Community.
Among the three techniques, the Systematic sampling had the fastest estimated sampling time of 12 hours and 36 minutes; whereas Random sampling estimated time was 12 hours, 44 minutes; and 13 hours for the Haphazard sampling method.
Among the two most common species: Eastern Hemlock and Sweet Birch, Haphazard sampling technique was relatively the most accurate giving the lowest percent error of 12.3% for Eastern Hemlock and 25.9% for Sweet Birch.
Random sampling technique gave the lowest percent error for Sweet Birch, 25.5%, which is very close to Haphazard sampling technique; and the second lowest percent error of 16.6% for the Eastern Hemlock species.
In all the three techniques, Systematic sampling seem to be the least accurate due to the highest percent errors in the most common species, 17.4% for Eastern Hemlock, and 28.7% for the Sweet Birch.
The two rarest species appeared to be the Stripped Maple and White Pine. In both Systematic and Random sampling technique the percent error values for the White Pine species is 100% because none of the White Pines were present in the selected samples. Similarly, the percent error is 100% in Stripped Mapple species using the Random sampling technique. However, the percentage error was the lowest, 31.4% in Stripped Maple species using the Haphazard technique; and 60% percent error using the Systemic sampling method. Lastly, the highest percentage error observed was 280% of the White Pine using the Haphazard sampling method.
According to the data above, the overall accuracy is higher in the most common species, and lower in the rarest species in all sampling techniques. So the more abundant the species, the higher the accuracy.
Overall the Haphazard sampling technique was relatively the most accurate of the three techniques.
Systemic should have been the most accurate for common species though I guess if you chose enough haphazard locations it could come out that way. Haphazard can be the most accurate for rare species which are harder to capture and sometimes require a different sampling approach to common species.