Populations in ecosystems Flashcards
What is succession?
A directional change in a community of organisms over time.
What is pioneer species?
The first organisms to colonize an area.
What is a climax community?
When a stable state is reached comprising of a balanced equilibrium of species with few, if any, new species replacing established ones. There is much biodiversity.
What is primary succession?
The simplest type of succession, beginning with a bare surface with little or no life or soil present.
What is secondary succession?
When events such as fires or landslides will disrupt succession or the continuation of the succession.
What is deflected/interrupted succession?
When the climax community is prevented from being established.
What is hummus and how does it change as the number of seres (stages in succession) changes?
Organic matter in the soil: improves water retention and provides nutrients. Increases as seres increases.
What is the maximum size population an ecosystem can carry called?
Carrying capacity.
What is an ecosystem?
Ecosystems are dynamic systems made up of a community and all the interactions between biotic and abiotic factors.
What is a community?
All the different species found within an ecosystem.
What is a population?
A population is a group of individuals of one species that occupy the same habitat at the same time.
What word is used to describe how an organism fits into its environment?
Niche.
What is a habitat?
A habitat is a place where an organism lives.
What factors can change carrying capacity?
This population size can vary as a result of:
• the effect of abiotic factors ( e.g.temperature, light)
• interactions between organisms: interspecific and intraspecific competition and predation.
What two ways can the size of a population be measured?
The size of a population can be estimated using:
• randomly placed quadrats, or quadrats along a belt transect, for slow-moving or non-motile organisms
• the mark-release-recapture method for motile organisms.
