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Results using the three sampling strategies on Snyder-Middleswarth Natural Area
Random Sampling
Total time to sample: 12hrs, 12 mins
% Error for Dominance
Most Common
Eastern Hemlock: 107 individuals, 15.9%
Red maple: 28 individuals, 17.1%
Least Common
Sweet Birch: 19 individuals, 14.3%
Yellow Birch: 17 individuals, 4.8%
Missed the striped maple and white pine entirely
Shannon-Wiener’s index of diversity for the community: 13.3%
Systematic Sampling:
Total time to sample: 12 hrs 12 minutes
% Error for dominance
Most Common:
Eastern Hemlock: 119 Individuals, 1.5%
Sweet Birch: 31 Individuals, 9.4%
Least Common:
chestnut oak: 11 individuals’, 50%
white pine: 2 individuals, 11.1%
Shannon Wiener’s index of diversity for the community: 6.6%
Haphazard Sampling:
Total time to sample: 13hrs
% Error for Dominance
Most Common Species:
Eastern Hemlock: 134 individuals, 5.4%
Yellow Birch: 34 individuals, 2%
Least Common Species:
Striped Maple: 8 Individuals, 157%
Chestnut Oak: 19 Individuals, 1.8%
Shannon Wiener’s index of diversity for the community: 6.6%
Comparing these three strategies it would appear that there is little meaningful difference in which one is most efficient with the time required to collect samples. Both the random and systematic sampling techniques requiring 12hrs and 12 minutes while the haphazard sampling required 13 hrs. In regards to the Shannon Wiener’s index of diversity for the community the haphazard and systematic sampling techniques only had a 6.6% error while the random sampling technique had a 13.3% error. The random sampling had relatively low % errors in the most common species (15.9% & 17.1%) and same for the most common species (14.2% & 4.8%); however, it missed two whole species present in the community. Systemic Sampling had low % errors in the most common species (1.5% & 9.4%), but with the least common species one high percent error 50%. Using Haphazard sampling had all percent errors under 6% except for in one of the two least common species a huge percent error of 157%. Due to these results I would probably deme random sampling the least accurate sampling method despite the haphazard sampling having one sample with 157% error, as it missed whole species and had the highest error Shannon Wiener’s index, while the Systematic Sampling was the most accurate on both accords. It seemed that the less abundant a species the more chance for high error, as they could be missed entirely. I would add that a stratified random sampling technique would probably have been the most accurate in this community as it seemed like some species were only present in small patches of land.
