19.6 Succession

Question 1

succession

Answer 1

describes changes in ecosystem over time in the species that occupy a particular area

Question 2

First stage of succession

Answer 2

The area is colonised by a pioneer species that are specially adapted to a hostile environment

Question 3

pioneer species adaptations

Answer 3

1. asexual reproduction to rapidly multiply
2. production of vast quantities of wind-dispersed seeds or spores to reach isolated areas
3. rapid germination of seeds on arrival(no dormancy)
4. able to photosynthesis
5. ability to fix nitrogen from atmosphere if soil has few nutrients
6. tolerance to extreme conditions

Question 4

as stages further

Answer 4

1. abiotic environment becomes less hostile
2. greater number of variety of habitats and niches
3. increased biodiversity
4. more complex foodwebs
5. increased biomass

Question 5

less hostile environment

Answer 5

soil froms(help retain water) nutrients are more plentiful

plants provide more shelter from wind

Question 6

increase in biodiversity

Answer 6

peaks in mid-succession

decreases to climax community as dominant species out-compete pioneer and other species, leading to elimination

Question 7

climax communities

Answer 7

stable equilibrium with prevailing climate

e.g. deciduous woodland in UK

Question 8

Secondary succession

Answer 8

sustained land is suddenly altered

succession is faster
-soil already exists
-spores and seeds survive
-influx of animals and plants through dispersal and migration

Question 9

conservation

Answer 9

management of earth’s natural resources by active intervention of humans to maximise use in the future

Question 10

reasons for conservation

Answer 10

personal
ethical
economic
cultural and aesthetic

Question 11

managing succession

Answer 11

prevent climax community woodland so gazing areas and meadows can be formed