Succession Notes

Range of Tolerance Optimum Range Stress Zone Intolerance Zone

Limiting Factors Sunlight Water/Humidity Nutrients

Succession The change in biological communities of an area over a long period of time

Two Types of Succession: Primary Initial establishment & development of a community occurs on barren rock volcanic eruption, glacial retreat, pavement Secondary Reestablishment of a community remnants of previous community is still there abandoned field, after fire, flood, or hurricane

Primary Succession:

Secondary Succession:

Stages of Succession: Bare Rock No soil, no available nutrients, no active life……not a community

Stages of Succession: Lichens & Mosses Pioneer Species First to colonize rocks secrete acid onto rock which liberates nutrients that can be absorbed catches wind-blown dirt can take 100s to 1000s of years very vulnerable to erosion least diverse and least stable

Stages of Succession: Grasses & Shrubs Early Succession Plants don’t need deep soil like full sun shrubs move in and shade out grasses, killing them

Stages of Succession: Softwood Early Mid-succession Plants trees that need a lot of sunlight Cedar, pine, aspen, locust Trees displace grasses and shrubs

Stages of Succession: Mid-succession Plants Tulip, ash, red maple, birch Displace the soft woods

Stages of Succession: Mixed Hardwood Mature Forest deciduous trees; oaks, maples, hickories, beech saplings are shade-tolerant for the first few years when an adult tree dies it leaves a hole in the canopy saplings race to the top, grow tall quickly-not wide then grow slowly Most Diverse, least likely to erode, very productive Dominant species is reproducing, therefore climax stage

Questions What is the difference between primary and secondary succession? What types of events can cause secondary succession? What are some abiotic and biotic factors that play a part in succession? How can humans cause succession?

Big Question How does the ecosystem change as it moves through the stages of succession?