Ecology, Ecosystem and Environment

Ecology Ecosystem and Environment

Ecology, Ecosystem and Environment


  • Environment is the natural component in which biotic (living) and abiotic (non-living) factors interact among themselves and with each other.
  • These interactions shape the habitat and ecosystem of an organism.
  • In a biological sense, the environment constitutes the physical (nutrients, water, air) and biological factors (biomolecules, organisms) along with their chemical interactions (chemical cycles ‚Ästcarbon cycle,¬†nitrogen cycle,¬†etc.) that affect an organism or a group of organisms.
  • All organisms are dependent on the environment to carry out their natural life processes and to meet their physical requirements (food, energy, water, oxygen, shelter, etc.).


  • The¬†biosphere¬†is the¬†biological component¬†(supporting life) of the earth which includes the¬†lithosphere, hydrosphere,¬†and¬†atmosphere.
  • The¬†biosphere includes all living organisms on earth,¬†together with the dead organic matter¬†produced by them.
  • The biosphere is¬†absent at extremes¬†of the North and South poles, the highest mountains, and the deepest oceans since existing hostile conditions there do not support life (life is the characteristic feature of the biosphere).
  • Occasionally spores of fungi and bacteria do occur at a great height beyond 8,000 meters, but they are metabolically inactive and hence represent only dormant life.


  • Habitat is the physical environment in which an organism lives (address of an organism).
  • Many habitats make up the environment.
  • A single habitat may be common for more than one organism which has similar requirements.
  • For example, a single aquatic habitat may support a fish, frog, crab, phytoplankton, and many others.
  • The various species sharing a habitat thus have the same ‚Äėaddress‚Äô. E.g. Forest, river, etc.

Difference between Habitat and Environment

  • A habitat always has life in it, whereas the environment does not necessarily have life in it.
  • All habitats are environments, but all environments are not habitats.
  • Habitat is always a¬†preference for¬†one species.
  • An environment could be a preference of many species that could eventually become many habitats.
  • Usually, the environment governs the properties of a habitat, but not vice versa.


  • An ecosystem can be visualized as a¬†functional unit of nature, where living organisms (producers, consumers,¬†and¬†decomposers) interact among themselves and also with the surrounding physical environment.
  • An ecosystem can be of any size but usually encompasses¬†specific and limited species. E.g.¬†Aquatic Ecosystem. (This is how the ecosystem is different from the Environment)
  • In the ecosystem, biotic and abiotic components are linked together through nutrient cycles and energy flows.
  • Everything that lives in an ecosystem is dependent on the other species and elements that are also part of that ecological community.
  • If one part of an ecosystem is damaged or disappears, it has an impact on everything else.

Classification of Ecosystems

  • Forests, grasslands, and deserts are some examples of¬†terrestrial ecosystems; ponds, lakes, wetlands, rivers, and estuaries are some examples of¬†aquatic ecosystems.
  • Crop fields and an aquarium are human-made ecosystems.

Difference between Ecology, Environment & Ecosystem

Difference between Ecology, Environment & Ecosystem
  • Ecology¬†is the study of interactions between organisms, organisms, and the surroundings occurring within an ecosystem or environment.
  • An ecosystem is a functional unit of the environment (mostly biosphere).
  • An environment is a group of ecosystems.
EnvironmentCan be almost everything or a small region.
HabitatArea where an organism lives.
BiosphereThe region on Earth that supports life
Ecosystem Producers, Consumers, Decomposers, and their relationships (tiny environment). It is the functional unit of the environment.

Related Links:

Understanding Crustal RocksEL Nino and LA Nina