Natural changes in ecosystems Flashcards
Australia has a variety of different climate and consequently different ________, each having their own unique ___________.
biomes
ecosystems
ecosystem characteristics and species composition are shaped by natural hazards such as: (3 things)
bushfire
drought
flood
Effect of bushfire is determined by: (3 things)
- frequency of the fire (how often they happen) it is difficult for plants to recover when fires are frequent
- intensity of the fire (how hot)- very hot fires occur when there’s lots of plant material at ground level (fuel). very hot fires kill seeds in the soil bank
- how fast the fire moves through an area- if fire is fast only ground surface plants are burnt, trees survive
Adaption to survive fire: kangaroos and birds ______ _____ when smoke warns of fire
move rapidly
Slow animals may _______ for protection
burrow
Some plants have ______ _____ for protection. Shoots arise from beneath the bark after fire (_________ shoots)
thick bark
epicormic
Some plants send up new____ from their ________ (e.g. from lignotubers)
shoots
roots
some plants have ______ ____ that need _____ from fire to ____ and _______ seeds.
seed pods
heat
open and release
__________ shoots sprout from beneath bark on trees
Epicormic
New shoots that sprout from tree roots beneath the ground
lignotubers
What is drought caused by?
climatic cycles of El Nino and La Nina
What occurs during El Nino?
Cool water currents in the pacific ocean bring dry conditions widespread in Eastern Australia
Lack of water changer populations of organisms and therefore entire food webs
that’s it
Floods can be damaging, but benefit ecosystems by: ( 3 things)
Clearing waterways
Depositing fertile soil
Replenishing underground water for plant use
