lecture 3: Geographies of biodiversity 3

Question 1

Plagioclimax (disclimax)

Answer 1

the arresting of the successional process by humans to maintain a particular community, e.g. grazing, burning

• If the anthropogenic disturbance is then removed, a climax community will develop – this is a subsere

Question 2

Ecological status

Answer 2

whether a community is seral, subclimax, plagioclimax or climax

Question 3

Succession- plant community

Answer 3

A plant community in a succession creates conditions which are more and more favourable to more complex and demanding communities which will out-compete and replace it. - Smithson

Question 4

Nudation

Answer 4

initial creation of bare surface

Question 5

Immigration

Answer 5

arrival of available propagules

Question 6

Ecesis

Answer 6

establishment of propagules

Question 7

Reaction

Answer 7

interaction of plants with each other and habitat

Question 8

Stabilization

Answer 8

creation of equilibrium communities

Question 9

Facilitation model

Answer 9

Follows an early theory of succession put forward by American Ecologist Frederick Clements around 1916

Question 10

Tolerance model

Answer 10

States that succession depends on the competitive abilities and life spans of the plants, so that longer-lived species persist

Question 11

Inhibition model

Answer 11

Initial plant cover modifies the physical habitat so that it is less favourable to colonisation by other species, and succession can occur only when the inhibitory species are removed