Chapter 5 Changing ecosystems

Question 1

explain the concept of ecological succession (refer to pioneer and climax communities and seres)

Answer 1

Ecological succession involves a series of stages: pioneer species create soil, followed by the development of intermediate communities known as “seres,” until a stable and diverse climax community is formed.

Question 2

pioneer species

Answer 2

annual plants grow, and grasses
-ability to fixate nitrogen, tolerance to extreme conditions, rapid germination of seeds, ability to photosynthesise
-effective colonisers

Question 3

intermediate species

Answer 3

shrubs, pines, young oak

Question 4

Climax community

Answer 4

-mature oak and hickory forests

Question 5

primary succession

Answer 5

The colonisation of plants in a bare area for the first time

Question 6

Secondary succession

Answer 6

Involves the recolonisation of plant communities in areas that were once vegetated, but have been disturbed

Question 7

predict the impact of human activity on the reduction of biodiversity and on the magnitude, duration and speed of ecosystem change

Answer 7

habitat destruction, pollution, and overharvesting, can greatly reduce biodiversity in ecosystems.
-Climate change, and land use changes can intensify the magnitude, duration, and speed of ecosystem changes.