Quicker than counting but accuracy only improves through practice. Uses the ACFOR Scale - Abundant, Common, Frequent, Occasional, Rare (DAFOR - Dominant, Abundant)
Point Frames:- used to make more accurate percentage cover estimates. It has 10 pins, each representing 1%. Lower the pins to the ground and record each species in contact with the tip of the pin as it is lowered - repeat 10 times per quadrat
Avoiding Biased Random Sampling
- Use random number generators to select coordiantes to place a a quadrat - found along two perpendicular tape measures
- Record the Distribution or Abundance of species in the quadrat - repeat 3 times and calculate the mean (inlcuding anomalies)
How many quadrats and how big:
- take random samples across the habitat and make a cumulative frequency graph - where this plateaus, is the minimum number of quadrats to use
- Repeat this using larger and larger quadrats to calculate the optimum size
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