Question

Wanting to investigate the dispersal pattern of red ozier dogwood (Cornus stolonifera) in the Edmonton river valley, you and your co-workers set-up 30 25x25m quadrats in the area and find that the average number of plants per quadrat is 12.8, with a variance (s²) of 44.89.

Does red ozier dogwood in the river valley exhibit a uniform, clumped, or random distribution? (use the variance to mean ratio on page 3-7 to help you, and assume that the V:M is calculated to be significant).

A) Random

B)Clumped

C)Uniform

Answer 1

If the variance/mean ratio is near 1, the distribution is Random.

If the variance/mean ratio is less than 1, the distribution is Uniform.

If the variance/mean ratio is greater than 1, the distribution is Clumped.

For the given data,

variance/mean ratio = 44.89 / 12.8 = 3.507

Since the variance/mean ratio is greater than 1, the distribution is Clumped.

B) Clumped