Ecological Sampling
Science: KS3, topic 1.3.12
Ecological Sampling
There are many kinds of sampling. Random sampling and line transects are forms of sampling.
Random sampling
- The sampling area needs to be mapped out for random sampling.
- The area should be mapped out with coordinates.
- Coordinates should then be chosen at random.
- Coordinate numbers should be chosen with a random number generator.
- This prevents bias.
- Bias can lead you to select areas with high or low organism numbers.
Random sampling results
- Once you have placed your quadrat, count the number of species present in the quadrat grid.
- You can also record the % coverage of the species.
- The % coverage is sometimes difficult to calculate.
ACFOR
- A range scale can be used instead of % coverage sums.
- ACFOR is a range scale.
- ACFOR stands for:
- A – Abundant 90-100%
- C – Common – 50 – 90%
- F – Frequent – 20 -50%
- O – Occasional 5 – 20%
- R – Rare – up to 5%
Line transect
- Line transect sampling uses a quadrat.
- Instead of random sampling, the quadrat is placed at regular intervals.
- The number of species can be recorded at regular intervals.
Test yourself on Ecological Sampling
Which form of sampling places quadrats at equal intervals?
What two things can you record for a species when you place a quadrat during random sampling?
Select the true statement about the ACFOR scale for each pair
Why are coordinates chosen using a random number generator in random sampling?