Succession Terms Match the words below to the definitions on your sheet

lichengrasstreeperennial shrublegumesserefernsalgaeflorahydrosere faunaxeroseremossfungiherbaceous

SuccessionWhat does the term succession mean?

The development of stable communities, or climax communities, takes place in a number of stages known as succession.Each different stage is called a seral stage or seral communitySuccession occurs due to the modifying effects of living organism on the environment.What are these modifying affects?

SuccessionExcretion and Dying are the two very important factors. Why? (KS4 Science!!)The nitrogen cycle! In order for plants to survive they nitrogen.What is nitrogen used for?Making amino acids, DNA and hormones Where do these nitrates come from?Organic matter in the soil (i.e. From excretion and dead organisms)

SuccessionWhat is a seral stage?As the plant life changes so does the fauna/animals that live in the area. The life present will change many times and we called these stages a seral stage . What is a sere?The whole process for a particular ecosystem is known as its sere e.g. Temperate forest sere, peat bog sere, xerosere, hydrosere

Succession When succession is started by the formation of totally new land, it is known as primary succession.Seral 1New land is referring to a newly formed land mass such as a volcanic island (bare rock), sand dunes or glaciated surfaces. When first formed these consist of pure rocks. Plants (flora) can not live here and so no animal life (fauna) can live here. These islands are very inhospitable. They are identified, mostly, by a almost total lack of soil.

SuccessionSeral 2The first species to colonise bare rock are lichens or algae. They are able to survive by absorbing nutrients from the air, rather than the soil. They are known as the pioneer community.Weathering of rocks and the increase in organic matter will eventually lead to a thin layer of soil forming by the end of this seral stage

SuccessionSeral 3With a soil layer present the mosses and ferns will be able to survive. These mosses and ferns dominate the area and the lichens die out due to competition for space.Seral 4Grasses are able to dominate forming a grassland habitat

SuccessionSeral 5The small herbaceous plants will then be replaced by shrubs forming scrubland Seral 6 Trees are the final seral stage. When woodlands or forests are formed this is known a climax community

http://techalive.mtu.edu/meec/demo/PrimarySuccession.html

Succession ChangesMany of these early plants are legumes and this helps to increase the fertility of the soil. Why?They can fix nitrogen in their root nodules and survive when less nitrogen is presentWhy can different flora colonize the same area?When the soil becomes more fertile and thicker, due to humus (organic content) and more weathering of the bedrock it can support larger flora. These larger flora will out compete the smaller flora for space and light. So they will die out.

Succession

Succession ChangesWhy are the early species annual and the later species perennial?Annual plant will live reproduce and die in one season where as perennial will live more than one season.

The soil will not support higher plants early on, so annual plants ensure they reproduce then die, this adds extra nitrates to the soil.

Succession ChangesAs succession continues biomass also increasesWhat happens to the biodiversity of the flora and fauna and succession occurs?Fauna always increases at each seral stage generally being the highest at the climatic communityThe flora will be greatest before the climax due to the dominance of the climax species (trees) which out compete other species http://www.nodvin.net/snhu/SCI219/demos/Chapter_4/Chapter_04/Present/animations/50_2_2_2.htmlhttp://www.nodvin.net/snhu/SCI219/demos/Chapter_4/Chapter_04/Present/animations/50_2_4_1.html

SuccessionSuccession ends when a climax community is reached. A climax community is normally a forest ecosystem as trees are the most efficient at using sunlight. At this point a community is in equilibrium with the climatic conditions.However in areas where climatic conditions do not suit trees other climax community can exist e.g. Moorland where conditions are acidic This is known as a plagioclimax (deflected climax ) or biotic climax

SuccessionHumans and animals can create plagioclimax due to management of the land e.g GrazingMowingFiresCoppicing These all stop climax communities forming but can increase biodiversity

Secondary Succession This term is applied when referring to succession that occurs on an area that has become bare due to fire or clearance (man).Succession occurs in exactly the same way but soil is already present and so the rate of each sere will be quicker

http://www.geowords.org/ensci/imagesbook/04_03_succession.swf

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