Talk:Ecological succession
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Part of this page was based on information once at an article called Vegetation succession. The page history of this is now at Talk:Ecological succession/Page history.
Moved the following idiosyncratic addition (it was also not integrated properly into article) from the main article. Addition is also full of external links to the author's website, rather than internal wikilinks to wikipedia articles which makes it look like a case of self-promotion. --Lexor 14:11, 28 Jan 2004 (UTC)
Ecological succession as a derivative of the Second Law of Thermodynamics (http://www.holon.se/folke/kurs/Distans/Ekofys/fysbas/LOT/LOT.shtml)
addition by Folke Günther (http://www.holon.se/folke/index.shtml)
Ecological succession is the spontaneous transformation of an ecosystem from a simple type (e.g. a grassland) into a complex type (ultimately: a tropical rainforest)
The process is driven by the Second Law of thermodynamics (http://www.holon.se/folke/kurs/Distans/Ekofys/fysbas/LOT/LOT.shtml) which is basic to any type of biological transformation.
Typical for a young (immature) ecosystem is:
- parasitism
- linear flows
- low diversity
- leakage
- matter export
- high excess production
- low exergy (http://www.holon.se/folke/kurs/Distans/Ekofys/fysbas/exergy/exergybasics.shtml) consumption capacity
A typical example of this is a grassland or agricultural land
A mature ecosystem is characterized by
- high diversity
- mutualistic interactions (i.e. interactions that in some way or another is beneficial for both parts)
- closed loops of nutrients
- high exergy consumption capacity
- all produced matter is consumed in the system
A typical example of this is a tropical rainforest, but other old forest ecosystems also approach this state.
A corollary of the above is that tropical rainforests do not provide oxygen, they breath it all up!
If an ecosystem is disturbed, it goes backwards in succession.
Looking at human-inhabited ecosystems then, the urban-agricultural system represent a young/immature system, while a self-sufficient village type represent a mature state.
For a closer discussion of this, see thermodynamics and ecosystems (http://www.holon.se/folke/kurs/Ecologicaldevelopment/Termodyn_en.shtml) and related links.
Simple vs. Complex
If a tree falls in a forest, and no ecologist is there to see it, does it make a gap? Yes, and this gap will lead to an increase in diversity, in contrast to the generalisation made above in regards to the 2nd law. It has also made it more complex, if we use information theory to quantify complexity. Sucession will undo this disturbance, leading the ecosystem towards a less diverse and less complex state. Other examples point to different trajectories, but I am wary of the statement in the first paragraph that requires complexity to necessarily increase. Daniel Collins 19:44, 21 May 2005 (UTC)