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In the virtual forest exercise, of all the three sampling methods on which I performed the sampling analysis, the haphazard sampling technique was the shortest with an estimated time of 1hr, followed by the area random or systemic which was 11 hours , 29 minutes and then a systemic sampling along a topographic gradient at 21 hours 23 minutes.
Of the two most common species, Red Maple and Witch Hazel, the hapharzard sampling had a percentage error of 0.9% for Red Maple and 0.3% for Witch Hazel. With random sampling, the percentage error was 1.4% for Red Maple and 1.5% for Witch hazel. With the systemic sampling along a topographic area, the Red Maple had a percentage error of 0.92% while the Witch Hazel had a percentage error of 1.53%. for these two common species, it would appear that the Haphazard sampling method had the lowest percentage error for both the Red Maple and the Witch Hazel. If you average the percentage error of the two sample techniques, the haphazard sampling method had the lowest percentage error for the common species of trees.
Of the two rarest species, White Ash and Yellow Birch the percentage error for the systematic sampling technique was -100% for both species. Random sampling had a percentage error of -100% for White Ash and 5.6% for Yellow Birch. For haphazard or subjective sampling, the percentage error for White Ash was 52.8% and -100% for Yellow Birch. The systemic sampling techniques failed to record any occurrences of both the White Ash and Yellow Birch trees. Random sampling had the smallest percentage error for White Ash making it the most effective sampling technique for this rare species.
Accuracy for all species was relatively consistent with the 3 sampling techniques except for the rarest species of the Yellow Birch and White Ash that was not detected with all methods. The most abundant species were more accurate while the least accurate was the haphazard sampling technique for White Ash which was at 52.8%.
Based on the results, all three sampling techniques showed fairly consistent results although random sampling appeared to be the most effective for the most abundant tree type. For the Yellow Birch, the random sampling method was the most effective with only a 5.6% percentage error. The White Ash tree had a percentage error of 52.8% with the haphazard sampling method which was the highest percent error for the rarest trees even though this method was the fastest method.
