Theory question 103
Population Ecology(a) Give a brief description of the characteristics of the Northern Guinean Savanna
(b) Describe how you can estimate the density of a plant species using a quadrat.
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(a) Rainfall about 1000–1500 mm with a long dry season (5–6 months); tall grasses (e.g. elephant grass, spear grass) in tufts; scattered trees of medium height with thick, fire-resistant bark and twisted trunks (e.g. shea butter, locust bean); many trees shed leaves in the dry season; frequent bush fires; deep roots and underground stems; many grazing animals
(b) Choose and mark out the study area; throw a quadrat (e.g. 1 m²) at random several times (e.g. 10); count the number of the chosen species in each throw; find the mean number per quadrat; density = mean number per quadrat ÷ quadrat area (number per m²); multiply by the total area to estimate the total number
Throw the quadrat at random several times and use the average.