Population growth

Slow growth

• few individuals at this point

• may take time to acclimatise to new environment

• rate of reproduction is low due to low number of organisms

• birth rate > death rate

Rapid growth

• larger number of breeding individuals present to birth rate increases

• resources are still sufficient to support the growing population

• exponential rate of growth

Stable state

• population size fluctuates depending on impact of limiting factors

• remains relatively stable

• birth rate approx.= death rate

Carrying capacity

• the maximum size of a population that can be supported over a long period of time in a particular habitat

Limiting factors

• limiting factor

  • anything that stops a population from increasing in size indefinitely

• Abiotic

  • temperature

  • light intensity

  • pH

  • water availability

  • oxygen availability

  • humidity

  • space

• biotic

  • predators

  • disease

  • competition

• density dependent

  • size of effect depends on size of population

  • diseases

  • parasites

  • predators

  • competition

• density independent

  • effects whole population regardless of size

  • earthquake

  • storms

  • fire

  • volcano