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Blog Post 4
Which technique is the most efficient in terms of time spent sampling?
Systematic: Sampling along a topographic gradient 4 hours, 5 minutes (20 minutes faster than haphazard)
This is from a distance based sampling strategy.
Percent error
Systematic: Sampling along a topographic gradient
Percent error common species (Eastern Hemlock): 12.9%
Percent error rare species (Striped Maple): 46.9%
Random: Distance, random or systematic
Percent error common species (Eastern Hemlock): 13.6%
Percent error rare species (Striped Maple): 58.9%
Haphazard or subjective sampling:
Percent error common species (Eastern Hemlock): 6.5%
Percent error rare species (Striped Maple): 100%
The most accurate sample strategy for common species was Haphazard or subjective sampling.
The most accurate sample strategy for rare species was Systematic: Sampling along a topographic gradient.
The accuracy for rare species declined over the sampling methods used.
The accuracy rate changed in relation to species abundance. The less abundant a species was correlated with a greater increase in error of collecting a sample for that species.
24 sample points was not enough points to capture the number of species in this community. In the Haphazard sample, the error rate of 100% would miss this species entirely. The sample strategy that most captured this species still had an error rate of 46.9%, which greatly under-represents this species. Adding more sample locations would reduce the error rate.
