1. Ecological Succession
Primary vs. Secondary Succession

2. Ecological Succession
Ecological succession is a series of predictable changes that occur in a community over long periods of time.

3. Rock Exposed from Glacial Melt
Primary Succession
Primary succession occurs in an area where there was no prior life.
Rock Exposed from Glacial Melt
Cooled Lava Flows
Rocky Cliffs

4. Pioneer Species
The first species to inhabit bare rocky surfaces and begin primary succession are called “Pioneer Species”.
Lichen (like-in) are a common example of a pioneer species. Lichen is a symbiotic organism composed of a type of fungus and a type of algae. The fungus secretes acid that slowly dissolves the rock to release nutrients. The algae is a producer that can carry out photosynthesis to create sugar. Both organisms help each other to survive . What kind of symbiotic relationship is this?

5. Primary Succession Continues
As moss grows and dies the amount of soil and nutrients increases allowing grass and small plants to grow.
As layers of pioneer species such as lichen die a thin layer of soil forms which is enough for moss to grow.
Succession continues as shrubs then fast growing trees like pines begin to grow followed by slow growing hardwoods like oak, hickory and maple

6. The climax community in the northeast is a hardwood deciduous forest
Succession continues until a mature, stable community is established. This is called a “climax community”.
The climax community in the northeast is a hardwood deciduous forest

7. Forest Fire Land Cleared for Farming Clear Cutting a Forest for Lumber
Secondary Succession
Secondary succession occurs in an area when a disturbance destroys the plant life but the soil remains so growth can occur faster.
Land Cleared for Farming
Clear Cutting a Forest for Lumber
Forest Fire