Succession

starting point of development mutualistic relationship between a fungus and an alga

starts in newly formed habitats process of colonisation

bare rock sand shingle open water

first organisms to colonise bare rock

extreme conditions no soil/ water / nutrients/ extreme temperatures

pioneer species colonise bare rock ps break up rock surface build up of organic material as they die, combines with rock fragments to make soil

start of soil change of conditions allows other species to grow eg. wind-blown moss spores

soil builds up and able to hold water shallow rooted plant species can germinate conditions continue improving- deeper rooted plants can colonise competition works

tall plants outcompete pioneer species replace these species

stable, final community is reached - may be one or several dominant species - community is complex - remains unchanged unless conditions in habitat change

xeromorphic/ xerophytic features + tolerant of salt spray underground stem systems to stabilise them grow faster when buried by sand small mini-dunes accumulate around stems

often nitrogen fixers cover dune surface limit wind erosion

bare soil where community has been cleared organic matter/ mineral content of soil is high likely plenty of light unlikely harsh abiotic conditions

small abundant seed production wind dispersed seeds fast germination and growth

human intervention prevents succession from running its course stable but NOT climax community