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Macrobiomes

Biomes

Ecosystems

Habitats

Image 8. Differences in size of macrobiome, biome, ecosystem and habitats.

Ecosystems and biomes - Kahn Academy

Biotic and abiotic interactions

If Macrobiomes, biomes, ecosystems and habitats are characterized by the different and multiple
interaction between the abiotic and biotic factors, how do these interactions are expressed?

Living organisms have different trophic levels, see Image 9. Trophic interaction (and resulting food
webs) is the most crucial interaction type between species and individuals, which it is also supported
by abiotic factors, such as sun light as energy source for primary producers, which use photosynthesis
as the process to transform sunlight into energy rich organic compounds.

Other interspecies relations:

• Mutual Beneficial Relations: symbiosis, such as commensalism (1 species benefit and other
gets neutral result from the interaction) or mutualism (both species benefit).
• Parasitic: one species benefits from the interaction, while the other suffers a negative impact.
• Competitive: 2 or more species compete for same resource(s); they co-exist in a balance, or
ultimately one specie will over power the other.

As biodiversity increases in a certain habitat / ecosystem, more complex will be species inter-relations,
especially when species evenness is high, resulting in ecosystem stability by the increasing ecosystem
resilience and resistance.

Ecosystem resilience: the ability of the ecosystem to recover, to its previous state, after
stresses and disturbances.

Ecosystem resistance: the ability of the ecosystem to maintain its structure, processes and
functioning unchanged, despite stresses and disturbances.

This project has been funded with support from the European Commission. This communication reflects the
views only of the author, and the Commission cannot be held responsible for any use which may be made of the

information contained therein.