Chapter 5: Changing Ecosystems Flashcards
What is ecological succession?
The progressive change of communities over time
What is primary succession?
The colonisation of plants in a barren place.
What causes primary succession?
Volcanic eruptions, cyclones, earthquakes and tsunamis
What are the stages of primary succession?
Nudation and pioneer plant
What is a pioneer plant?
A plant capable of invading a bare site
Why are pioneer plants good?
They are capable of surviving in low nutrient soils, fixate nitrogen, rapid germination of seeds and survive extreme conditions. This makes them extremely good colonisers
What is r-selected species?
Pioneer plants, they show J-curve growth
What is secondary succession?
Disturbed communities which get recolonised
What is climax communities?
The end of succession where the community becomes stable
What is k-selected species?
A slow growing, long-lived species typical of those in a climax community
Does all succession reach climax?
No, a multitude of conditions can cause the growth to become stable and ecosystem persist
What are palaeontologist?
People who study the science of life that existed
What is Pangaea?
The supercontinent consisting of all of Earth’s masses
How do biotic features help us understand changed in ecosystems over time?
They can compare present biotic features to fossil records.
How does human activity impact biodiversity on the magnitude, duration and speed of an ecological change?
Urbanisation, habitat destruction, land and soil degradation, salinity and monoculture practices
