Population Growth and Resource Availability - AP Environmental Science

Exponential growth model. Assumes infinite resources and no environmental resistance to growth.

Biotic factors are living; abiotic are non-living elements. Distinguishes between living organisms and physical environmental components.

Competition for resources. Effect intensifies as population density increases.

Increases population size. Fewer deaths means more individuals survive to reproduce.

Population decline or collapse. Overshoot leads to resource depletion and population crash.

Population growth slows as it approaches carrying capacity. Environmental resistance increases as population approaches $K$.

Shift from high birth and death rates to low rates as a country develops. Economic development typically reduces birth and death rates over time.

Exponential growth. Growth rate remains constant regardless of population density.

Population size remains stable. Zero population growth occurs when births equal deaths.

Limited food supply. Resource scarcity reduces reproductive success and survival.

Carrying capacity. Maximum sustainable population size for a given environment.

Maximum reproductive capacity under optimal conditions. Theoretical maximum growth rate without environmental limitations.

Predation. Density-dependent factor that removes individuals from population.

Exponential growth model. Humans show J-shaped growth despite resource limitations.

Decreases population size. Net loss of individuals reduces total population size.

$N_t = N_0 e^{rt}$. Models unlimited growth where population multiplies by constant factor over time.

Carrying capacity is the maximum population size an environment can sustain. Environmental limit determined by resource availability and space constraints.

An S-shaped curve. Initial slow growth accelerates, then levels off at carrying capacity.

Limited resources slow population growth. Scarcity creates competition and density-dependent factors that reduce growth rates.

$N_t = \frac{K N_0}{N_0 + (K - N_0)e^{-rt}}$. Accounts for environmental resistance that slows growth near carrying capacity.

Time period over which growth is measured. Time variable represents duration of growth or observation period.

Limits population size through resource scarcity. Intraspecific competition intensifies as resources become scarce.

A resource that restricts population size. Environmental factor that prevents populations from reaching biotic potential.

Intrinsic rate of increase. Maximum per capita growth rate under ideal conditions.

Increases population size. More births than deaths leads to population expansion.

Factors that limit population growth. Combined biotic and abiotic factors that limit population growth.

Agriculture. Human activities can increase or decrease environmental carrying capacity.

$r = \frac{\text{births} - \text{deaths}}{N}$. Measures net change in population size per individual.

Exponential growth. Characteristic shape of unlimited exponential population growth.