populations in ecosystems

• populations

  a group of organsims of the same species living in the same habitat
• habitat


  part of an ecosystem in which particular organisms live.
• community

  all the populations of different species in the same area at the same time.
• ecosystem

  a community and non-living components of the environment (abiotic & biotic).
• niche

  an organisms role within an ecosystem, including their position in the food web and habitat.
• carrying capacity

  the maximum population size an ecosystem can support
• abiotic factors

  non-living conditions of an ecosystem
• biotic factors

  impact between interactions of living organisms
• whats three examples of abiotic factors?

  temperature

  light intensity

  oxygen concentration

  soil pH
• what are two examples of biotic factors

  competition

  predation
• what are the two types of competition

  interspecific

  intraspecific
• what is interspecific competition?

  members of different species are in competition for the same resource that is in limited supply.

  eg. food/ water
• what is intraspecific competition?

  members of the same species are in competition for resources and a mate.
• estimated total population = ( number or organisms initially caught x number of organisms in second sample ) / number of marked organisms recaptured
• primary succession

  starts with a pioneer species colonising harsh environments eventually converting them to be less harsh.

  eg. lichen moss
• secondary succession

  the succession is disrupted and the plants are destroyed then succession starts again from the soil since it is already there.
• as succession goes on the species richness and the number of species increases.