Population Ecology - Ch. 19 Flashcards
ecology
scientific study of the interactions between organisms and their environment
population
a group of interacting organisms of the SAME species that occupy a specific area at the same time
community
populations of DIFFERENT species occupying a particular place at the same time
ecosystem
a community of species combined with their abiotic (nonliving) environment
population ecology
Factors that influence a population’s:
- size
- density
- growth rate
- structure (relative number of individuals of different ages)
population density
number of individuals per unit area
What are some ways of measuring population density?
- Counting all the individuals
- Estimating
- Indirect Indicators - Mark-Recapture Method
patterns of dispersion
the way that individuals are spaced within a population’s geographic range
What are the 3 kinds of patterns of dispersion?
- Clumped– results from unequal distribution of resources
- Uniform– results from interactions among individuals in populations
- Random– patternless and unpredictable, usually found in plants
What is the exponential growth model?
- rate of expansion under ideal, unregulated conditions
- population multiple by a constant factor during constant time intervals
- “J” curve
What is the logistic growth model?
- idealized population growth that is slowed by limited factors
- “S” curve
carrying capacity
number of individuals in a population the environment can maintain with no net gain or loss
density-dependent factors
population-limiting factor whose effects intensify as the population increases in size, e.g., limited food supply, buildup of poisonous waste, etc.
density-independent factors
population-limiting factor whose intensity is unrelated to population density, e.g., season weather changes, environmental trauma
biotic potential
ability to produce offspring
