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Flashcards in Succession Deck (7)
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What is succession

It is the process of ecosystem change


How may a species alter an environment when it colonises there

It might make it :

Less suitable for the existing species. As a result the new species may out compete the existing one and so take over a given area

More suitable for other species with different adaptations. As a result this species may be or competed by the better adapted new species


Describe primary succession

1) Primary succession- Species colonise a new land surface. Seeds and spores bloom in by the wind and begin to grow. This is called the pioneer species

Abiotic conditions are hostile (harsh). Only pioneer species grow because they’re specially adapted to cope with the harsh conditions

The pioneer species change the abiotic conditions- they die and microorganisms decompose the dead organic materials. This forms a basic soil.

Making conditions less hostile. Soil helps retain water, which means new organisms with different adaptations can move in and grow. These then die and decompose adding more organic material, making the soil deeper and richer in minerals. Shrubs can start to grow in the deeper soil, which retains even more water

Some new species may change the environment so that it becomes less suitable for the previous species


Describe secondary succession

Already a soil layer

The pioneer species in secondary succession are larger plants


What happens after secondary succession

Different plants and animals that are better adapted for the improved conditions move in, out compete the plants and animals that are already there, and become the dominant species in the ecosystem

As succession goes on the ecosystem becomes more complex. New species move in alongside existing species which means that biodiversity increases

The final stage is called the climax community - the ecosystem is supporting the larger and most complex community of plants and animals it can. It won’t change much more - it’s in a steady state


What’s the difference between primary and secondary succession

Primary happens on newly formed land

Secondary is where there is soil remains but no plants


What are the comment features during succession that emerge

Non living environment becomes less hostile leading to a

greater number and variety of habitats and niches that then produce

an increased in biodiversity then this leads to

more complex food webs and the leading to

an increased biomass