Key Concepts in Ecology: From Biosphere to Niche

Key Concepts in Ecology

Interdependence in Ecology

Ecology is the study of the interactions between organisms and the environment. Interdependence is a key theme found throughout ecology.

Levels of Organization in Ecology

  • Biosphere: The most inclusive level of organization (broadest).
  • Ecosystem: Smaller units that compose the biosphere.
  • Community: All the interacting organisms living in an area.
  • Population: Members of a species that live in one place at one time.
  • Habitat: The place where an organism lives.

Environmental Factors

  • Biotic factors: All living parts of the environment.
  • Abiotic factors: Non-living factors.
  • Acclimation: The process of adjusting tolerance to abiotic factors.
  • Dormancy: A state of reduced activity during unfavorable conditions.
  • Migration: Movement to a more favorable environment.

Energy Transfer in Ecosystems

  • Producer: Autotrophs that can make their own food.
  • Chemosynthesis: The use of energy stored in inorganic molecules to produce carbohydrates.
  • Biomass: Organic material that has been produced in an ecosystem.
  • Consumer: Heterotrophs that eat other organisms.
  • Herbivore: Organisms that eat producers.
  • Carnivore: Organisms that eat consumers.
  • Omnivore: Organisms that eat both producers and consumers.
  • Detritivore: A type of consumer that feeds on garbage.
  • Decomposer: Organisms that break down complex molecules into simpler molecules.

Ecological Relationships

  • Food chain: A single pathway of feeding relationships.
  • Food web: A system of interlocking and interdependent food chains.

Biogeochemical Cycles

Biogeochemical cycle: The pathway by which a chemical substance moves through the living and non-living components on Earth.

  • Groundwater: Water in the soil or in underground formations of porous rock.
  • Water cycle: The movement of water between various reservoirs.
  • Transpiration: The process by which water evaporates from the leaves of plants in terrestrial ecosystems.
  • Carbon cycle: The biogeochemical cycle by which carbon is exchanged among the biosphere and atmosphere of the Earth.
  • Nitrogen cycle: The complex pathway that nitrogen follows in an ecosystem.
  • Ammonification: The process in which ammonia released by decomposers becomes ammonium in the soil.
  • Nitrification: The process in which soil bacteria take up ammonium and oxidize it into nitrites.
  • Denitrification: Occurs when anaerobic bacteria break down nitrates and release nitrogen gas into the atmosphere.
  • Phosphorus cycle: The movement of phosphorus from the environment to organisms and then back to the environment.

Ecological Niche

Niche: A position or role taken by a kind of organism within its community.