ECOLOGICAL SUCCESSION Ecosystems tend to change with time until a stable system is formed. The stable system that will form depends on climatic limitations.

ECOLOGICAL SUCCESSION Ecosystems tend to

change with time until a stable system is formed.

The stable system that will form depends on climatic limitations.

Ecological Succession The replacement of

one community by another until a stable stage is reached is called ecological succession.

Climax Community The final stage of

succession is called the climax community.

The climax community in New York State is an oak-hickory forest or a maple-beech forest.

Primary Succession Primary succession

occurs where there was no previous community, such as on bare rock or sand.

Primary succession begins with pioneer organisms.

Pioneer Organisms Pioneer organisms

can tolerate extreme conditions: hot and cold; dry and wet.

Moss, dune grass, and lichens are pioneer organisms.

Lichens Lichens are algae and

fungus growing together in a mutualistic relationship. Algae make the food; fungus anchor and capture water.

Pioneer organisms Soil is produced over

hundreds of years by pioneer organisms.

These organisms break apart rock, add humus as they die and decompose, and hold water

This allows other organisms to grow there.

Succession occurs BECAUSE Each community

changes the conditions so that they are more favorable to other organisms that replace them.

For example, some types of trees need a lot of sun and their saplings cannot grow under the shade of their own species.

They will be replaced by the types of trees whose saplings can grow in shade of other trees.

Secondary Succession When a community is

disrupted and succession occurs again, it is called secondary succession.

Disruption may be from fire, farming, wind, foresting

Secondary Succession The community

begins again where the former community was disrupted.

Soil is already present.

A community is still undergoing succession As long as the species

keep changing: Here, the plants

growing under the pine trees are NOT small pine trees, so the species will be changing as the old pine trees fall.

Climax Community The same climax

community will develop unless the abiotic conditions have changed.

We can tell it’s a climax community- A climax community

replaces itself with more of itself:

Under sugar maple trees, we will see sugar maple saplings-that shows that it is a climax community

Climax Community The climax

community will be part of the BIOME of that area.

Our climax community- oak/hickory forest-is part of the temperate deciduous forest biome