3.7.4 Populations In Ecosystems Flashcards
What are abiotic and biotic factors
Biotic = living factors
abiotic= non living factors
Niche
Role of a species with interactions of
Biotic and abiotic factors
Carrying capacity
Maximum size of population an ecosystem can support
Intraspecific and interspecific competition
Infraspecific=competitiobetween the same species
Interspecific = competition between different species
Population change due to predator-prey relationships.
Prey is eaten by predator, resulting in the population of predators increasing and population of prey decreasing
fewer prey means increased competition for food so population of predators decreases
Fewer predators means more prey survive so the cycle begins again.
Population change due to predator-prey relationships.
Prey is eaten by predator, resulting in the population of predators increasing and population of prey decreasing
fewer prey means increased competition for food so population of predators decreases
Fewer predators means more prey survive so the cycle begins again.
How is mark - release-recapture used to estimate population size.
Sample is captured, marked, and released into same the area.
After a certain period of time another sample of animals are recaptured and marked organisms are counted.
Equation for mark-release- recapture
Population size= (number of individuals in first sample X number of individuals in second sample)
/ number of marked individuals recaptured
How are ecosystems dynamic
Populations rise+ fall
Small changes can have a large effect
Biotic and abiotic factors may alter the conditions of the ecosystem
What is primary succession
An area previously with no life is colonised by pioneer species.
What occurs during primary succession
- Pioneer species are able to survive the harsh conditions/ abiotic factors
- The pioneer species change the abiotic factors when they die as decomposition of dead matter adds nutrients to the ground forming basic soil.
- Due to less harsh conditions new species are able lo survive in the area
- This will form a climax community
What is a climax community
The final stage of succession where the ecosystem is balanced and stable
What is the difference between primary and secondary succession
Primary = starts on new land
Secondary = starts on a soil layer
What is conservation
Protection and management of species and habitats in order to maintain biodiversity.
