Aquatic ecology and Biodiversity

Unit 4- Community ecology

4.1.8. Ecological succession
It is the process of development of new communities is called ecological succession. It can be defined as “an orderly and progressive replacement of one community by another till the development of a stable community in that area” (Smith, 1965).

Characteristics of succession
• The succession is caused due to the modification of the habitat
• The kinds of programs changes continuously with succession
• The diversity of species increases. biomass can also increases
• Series of communities develop and they replace one another in an orderly sequence until the stable community is established. The first stage of community is ‘pioneer community’ The final stage of community called ‘climax community’
Types of succession
• Primary succession – Bacteria, Lichens – first community (pioneer) on rocks – biofilm
• Secondary succession-Attached of spats of barnacles, oyster, polychaetes etc. on pioneer communities
• Autotrophic succession - Dominance of algae.
• Heterotrophic succession – Dominance of heterotrophs