7. Ecological Succession 7.1 Succession. Starter Match up the key word to the definition Ecosystem...
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Transcript of 7. Ecological Succession 7.1 Succession. Starter Match up the key word to the definition Ecosystem...
7. Ecological Succession
7.1 Succession
Starter Match up the key
word to the definition
Ecosystem
Biotic
Abiotic
Community
An ecological factor that makes up part of the non-biological
environment
More or less self-contained functional unit in ecology made up
of all the interacting biotic and abiotic factors in an area
The organisms of all species that live in the same area
An ecological factor that makes up part of the living environment
of an organism
Learning Objectives
Describe changes that occur in the variety of species occupying an area over time
Define succession and climax community
Success Criteria You can describe the order of plant
succession and explain common features of succession
Succession
The changes, over time, in the species that occupy a particular area
Succession of bare rock or barren land Succession happens when an area is first
colonised. What might happen to cause this?A retreating glacier depositing rockWind or sea piling sand into dunesVolcanoes erupting and depositing lavaLand subsiding and creating lakes or pondsSilt and mud being deposited at river
estuaries
Pioneer Species
The first stage of succession involves pioneer species colonising an inhospitable environment
Pioneer species have features that suit them to colonisation
Task
In pairs, come up with a list of features that pioneer species may have, which would help them to colonise inhospitable environments
Features of Pioneer Species
Production of a lot of wind-dispersed seeds to easily reach isolated areas
Rapid germination of seeds The ability to photosynthesise The ability to fix nitrogen from the
atmosphere Tolerance to extreme conditions
Stages of Plant Succession
Stages of Plant Succession
Colonisers (lichens): when they die, they release nutrients. This changes the abiotic environment by creating soil.
Mosses, then Ferns: rock is continually eroded, as these die organic matter increases, building up soil
Small flowering plants, shrubs then trees establish
Climax Community
The organisms that make up the final stage of ecological succession
A balanced equilibrium In the UK, this is deciduous woodland
Animal Succession
Animal species present depend on the plant species found in the area
For example, mosses and grasses provide food and habitats for insects and worms. These can then support secondary consumers.
Common features in any succession The non-living environment becomes less
hostile A greater number and variety of habitats Increased biodiversity More complex food webs Increased biomass
Land alteration Succession also occurs when land is
suddenly altered e.g. from a fire The area will then undergo succession to
return to a stable, climax community This type of succession doesn’t begin with
a pioneer species
Learning Objectives
Describe changes that occur in the variety of species occupying an area over time
Define succession and climax community
Success Criteria You can describe the order of plant
succession and explain common features of succession