Ecological succesion Flashcards
What is succession?
The changes overtime, in the species that occupy a particular area
What is the Pioneer species?
The first species that colonises an inhospitable environment
How do Pioneer species colonise in inhospitable environments?
They have feature which suit them to colonisation:
1) Tolerance to extreme conditions i.e. heat
2) The ability to fix N from the air
3) Germinate
4) Photosynthesis
What are the 5 steps of plant succession?
1) Colonise
2) Pioneer species
3) Herbaceous plants
4) Shrugs
5) Climax
What is the role of colonisers?
Release nutrients upon death which changes the abiotic environment by creating soil
What happens in the Pioneer stage?
Rock is continuously eroded which increases organic matter and builds up soil
Which type of succession doesn’t start with the pioneer species?
Land alteration- after sudden alteration of land the area will undergo succession to return to a stable climax
What is the difference between primary succession and secondary succession?
Primary succession starts with bare rock or sand and secondary succession starts with soil
How do lichens prepare the environment for succession?
They provide a symbiotic relationship between a fungus and an alga
How do the pioneer species change the abiotic environment?
They start to weather rock and so begin to form very thin soil
How do the grasses and ferns continue succession?
1) Larger roots continue to weather the rock
2) Outcompete the pioneer species
What adds to the stability of climax communities?
1) Greater amount of species present
2) More complex food webs
3) The change in one species will have little effect on others
4) Species have more than 1 food source
