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In the virtual forest tutorial, I tried sampling techniques to compare their accuracy.
Haphazard (Area-sample)
- Total quadrats sampled: 5
- Area sampled: 500 sq. m
- Species sampled: 6
- Total specimens sampled: 39
There was an estimated sampling time of 2 hours 42 minutes. The error percentage for the 2 most common species was 13.9% and 34.2%. The error percentage for the 2 rarest species was 344% and 57%.
Haphazard (Distance-sample)
- total points sampled: 5
- species sampled: 5
- total specimens sampled: 20
There was an estimated sampling time of 59 minutes. The error percentage for the 2 most common species was 42.3% and 28.1%. The error percentage for the 2 rarest species was 72% and 44%.
Systematic (Area-sample)
- Total quadrats sampled: 5
- Area sampled: 500 sq. m
- Species sampled: 6
- Total specimens sampled: 34
There was an estimated sampling time of 2 hours 39 minutes. The error percentage for the 2 most common species was 4% and 43.6%. The error percentage for the 2 rarest species was 47.1% and 43.6%.
Systematic (Distance-sample)
- Total points sampled: 5
- Species sampled: 7
- Total specimens sampled: 20
There was an estimated sampling time of 59 minutes. The error percentage for the 2 most common species was 13.2% and 12.9%. The error percentage for the 2 rarest species was 51.5% and 11.8%.
From these results I determined that the distance method is the fastest way to sample. When comparing the error percentage of the different strategies for the 2 most common and 2 rarest species, it seems the accuracy does change with species abundance. Generally speaking, the systematic distance sampling method was more accurate than the haphazard one.
