2.5 Natural Disruptions to Ecosystems

Resistance

ability to remain unchanged when being subjected to disturbance

Resilience

ability and rate of an ecosystem to recover from a disturbance and return to its pre-disturbed state

Intermediate Disturbance Hypothesis

Ecosystems require a certain level of disturbance for maximum health and diversity; without any disturbance, a few species will eventually dominate a system. With disturbance, the organisms that manage to survive are the healthier ones, so organisms with less healthy genes will be eliminated. There needs to be fresh starting-over periods for every ecosystem.

* allow for specialization
* access to light, hiding places, and food

How can organisms benefit from living in an intertidal zone?

* seed germination
* clear brush
* open clearings for new plants

What are the benefits of forest fires on a ecosystem?

Frequency and Intensity

What makes modern-day change, with anthropogenic causes, different from all the previous natural change?

inverse relationship: as temperature increases, there are less oxygen isotopes

What kind of relationship do oxygen isotopes and temperature have?

small changes in earth’s orbit around the sun

What affects the distribution of solar energy reaching the planet?

human industry & agriculture

What are the rise in CO2 levels linked to?

CO2 is increasing 100 times faster than any time in the last 800,000 years. Before the last 20,000 years, CO2 levels would rise and fall consistently.

Why are the current CO2 levels concerning?

amount of solar radiation hitting the Earth and composition of Earth’s atmosphere

What is earth’s climate change mainly influenced by?

changes in climate or sea level, natural disasters, difference in rainfall

What are natural causes for climate change?

find food & water, prey on animals that migrate, provide for offspring

What are some reasons for animal migration?

Climate change impacts migrating animals because it changes their migration pattern especially animals who migrate seasonally. Animals will have to adapt to changing temperatures and biomes by changing the time they migrate, destination, or route.

How does climate change impact migrating animals?