topic 3

Question 1

succession explained

Answer 1

organsims adapedto extreme abiotic conditions-pioneer species
pioneers make habitat more suitable -new colonisers outcopete pioneer
further suitability invites new species
climax community will form

Question 2

Hydrosere

Answer 2

algae-seed/spore dispersal by birds-reeds at lake edge too deep
increase in DOM as plants die-as DOM INCREASES become shallower-rooted plants can grow-reduce light for macrophytes at water bed
bigger plants colonise

Question 3

lithosere

Answer 3

bare rock-lichen-thin layer of soil-pollination-more comolexed plants

Question 4

psammosere

Answer 4

sand stabililsed -reduced drainage rate +nutrient supply

Question 5

conservation of plagioclimax community

Answer 5

mowing
grazing or burning
ploughing
felling
coppicing

Question 6

population dynamic factors + importance

Answer 6

density in/dependant
death/birth rate
r/k selected species
needed to know the MSY

Question 7

carrying capacity

Answer 7

gretatest population an are a can hold without damaging indefinitely

Question 8

predator prey relationship

Answer 8

fluctuates as prey decreases predators decrease short lag time

Question 9

artificial population control

Answer 9

culling
captive breeding

Question 10

taxonomy

Answer 10

grouping of organisms
subjective-cant always accurately distiinguish between close species

Question 12

niche

Answer 12

a specifc role of a species in a habitat

Question 13

biome

Answer 13

large geographical region with specific climatic condtions