14.5 Ecological Succession

OBJECTIVE

Students will describe the process of primary succession and will be able to explain the difference between primary and secondary succession.

14.5 Ecological Succession

Standard

6b. Students know how to analyze changes in an ecosystem resulting from changes in climate, human activity, introduction of nonnative species, or changes in population size.

14.5 Ecological Succession

KEY CONCEPT Ecological succession is a process of change in the species that make up a community.

14.5 Ecological Succession

Succession 1) to create a community in a previously uninhabited area (nothing was living there before) OR

is the sequence of biotic changes that regenerate (repair) a damaged community

14.5 Ecological Succession

• There are two types of succession.1) primary succession — the development of an ecosystem in a previously uninhabited area (nothing lived there before-IT WAS ONLY ROCK!!!!)

14.5 Ecological Succession

Pioneer species- the first organisms that live in a new area Ex: lichen and some mosses break down rock into soil over time

12

3

41- Bare rock is exposed and lichen and moss break it down to dirt 0-15 yrs

2-Seeds are blown into the area and small shrubs grow 15-80 yrs

3-As soil grows thicker, small trees take root 80-115 yrs

4-Different tree species take root, and replace the old trees 115-200 yrs

14.5 Ecological Succession

2) secondary succession — started after a disaster by the remaining species (soil was left intact)

There is already soil!

0-2 yrs 2-18 18-70 70-100

14.5 Ecological Succession

Why do you think secondary succession takes less time than primary succession?

Secondary succession starts with soil instead of bare rock.