Edge effects (ecology)

Ecological concept

In ecology, edge effects are changes in population or community structures that occur at the border of two or more places of living.[1] As the edge effects get bigger, there is greater biodiversity in the habitat at the border.

Edges arise where two or more habitat types come into contact as here in Pennsylvania, United States. Very stable environment.
Okavango River, Botswana/Namida/Angola.
Extreme seasonal climatic changes
Okefenokee swamp
  • Permanent – the border location doesn't change with natural features.
  • Gotten – some natural disasters (e.g., fire or flood) or human activities, subject borders to straight changes over time.
  • Narrow – one habitat ends and another begins immidiately (e.g., an agricultural field).
  • Wide (ecotone) – a large distance separates the borders of two clearly defined habitats based on their physical conditions, and in between there exists a large transition region.
  • Complex – the border is chaotic.
  • Holes – the border has gaps where other habitats exist.

Height can create borders between patches as well.[2]

Biodiversity

change

Some plants and animals can be active on habitat borders because of environmental conditions. Larger patches allow more individuals and biodiversity becomes bigger. When the plants get more light, there are more types and different sizes. After it is possible to live for herbivorous insects, then birds some bigger animals.

There are three important factors:

  • Abiotic effect (changes in the environment);
  • Direct biological effects (the diversity of species reduces because of physical conditions near the edge);
  • Indirect biological effects (changes in species interactions).[3][4]

Human effects

change

Human activity creates edges through development and agriculture. Often, the changes are harmful to the size of the habitat and to species. Examples of human impacts:

References

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  1. Levin, Simon A.; Carpenter, Stephen R. (2009). The Princeton guide to ecology. Library Genesis. Princeton : Princeton University Press. ISBN 978-0-691-12839-9.
  2. Smith T.M. & R.L. 2009. Elements of ecology, p391–411.
  3. Valentine, Ethan C.; Apol, Chad A.; Proppe, Darren S. (2019). "Predation on artificial avian nests is higher in forests bordering small anthropogenic openings". Ibis. 161 (3): 662–673. doi:10.1111/ibi.12662. ISSN 1474-919X. S2CID 91309233.
  4. "Outlook Web App". owa.stevenson.edu. Retrieved 2021-03-15.
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