6. Ecosystem Engineers Flashcards
What is an ecosystem engineer?
Organisms that modify or maintain a habitat
Give examples of how humans are ecosystem engineers?
Dams, bird boxes
What are the two main ecosystem engineer types
Allognenic and autogenic
What is an allogenic engineer?
Change the environment by transforming living or non living materials from one physical state to another
What is an autogenic engineer?
Change the environment just by existing, decomposing,
Which allogenic engineer builds dams?
Beaver
Why do beavers build dams?
Protection, shelter, food stores he
What does the created porcupine do to change the environment?
Digs large soil pits, supports higher species richness
What is a geomyidae?
Pocket gopher
How is the gopher adapted to its environment?
Powerful digging muscles, tolerant of low co2 levels
What are the direct impacts from gophers?
Eat plants, move plants
What indirect do gophers have on the environment?
Making mounds, creating different eco climates
Why do gophers do so much damage to plants?
Eating 25% of the root is worse than 75% of the leaves
How deep are gopher tunnels?
6-20cm horizontal
Where is soil deposited?
Mounds or backfill tunnels
How much more energy does digging as a gopher use up?
360-3400 times
How much soil do gophers move a year?
17.8m3 ha per year
What does the gopher do to the soils?0
Verticals and horizontal soil mixing, sediment transport
What effect do gophers have on plant speciation?
Enhances germination, seedling mortality
Give examples of autogenic engineers?
Trees coral and giant kelp
What trees grow in the California steam belt?
Red woods
What do redwoods facilitate?
Colonisation by providing structure for growth
How high can trees grow on redwoods?
98m
What forms from the red woods which also facilitates growth?
Canopy soil
