Changes To Ecosystems + Ecological Terminology Flashcards
(29 cards)
What is ecological succession?
The gradual change in the structure and composition of species of a community in an area of land over time as abiotic factors become modified by previous communities.
What are abiotic factors?
- Temperature
- Light
- pH
- Water
- Humidity
What are biotic factors?
- Food availability
- Competition
- Predation
What is a sere?
The sequence of changing communities during ecological succession.
What are pioneer species?
Species that colonize first in a barren environment and alter conditions to make them less hostile.
What is the climax community?
A stable state with high ecological diversity where few species replace established ones.
What initiates primary succession?
Begins in a place without any soil, such as bare rock, sand, or after a lava eruption.
Name an example of a primary colonizer.
Lichens.
What is the role of lichens in primary succession?
They increase soil nutrient content, produce humus, and change pH.
What are the stages of primary succession?
- Pioneer stage (lichens)
- Secondary colonizers (mosses)
- Grasses, shrubs, small herbs
- Mature trees
What is mutualism?
A relationship where both organisms benefit from the interaction.
What is biological weathering?
The process where organisms erode rock, contributing to soil formation.
What is secondary succession?
Occurs when an existing community is disturbed but the soil remains intact, allowing faster recovery.
Fill in the blank: The initial species in secondary succession are typically _______ that grow quickly in the conditions present.
seeds
What is a plagioclimax?
A community that results from deflected succession, not reaching the expected climax community.
What are common features of succession?
- Non-living environment becomes less hostile
- Increased biodiversity
- More complex food webs
- Increased biomass
What is a hydrosere?
A succession that occurs in a fresh water environment.
What happens during the hydrosere process?
- Sediments wash into the lake
- Emergent species establish
- Water depth decreases
- Marsh plants thrive
What is the role of spores in primary succession?
They are wind dispersed and allow pioneer species to colonize barren environments.
What is the difference between primary and secondary succession?
Primary succession starts without soil; secondary succession occurs in areas where soil remains intact.
What are common management strategies for plagioclimaxes?
- Grazing or burning
- Mowing
- Ploughing
- Coppicing
What is the significance of the climax community in ecological studies?
It represents a stable ecosystem with a balanced equilibrium of species.
What is the typical soil condition during the pioneer stage?
Shallow soil with low nutrients.
What adaptations do pioneer species typically exhibit?
- Asexual reproduction
- Rapid germination
- Photosynthesis capability
- Nitrogen fixation
