Science of Water : Concepts and Applications

Water Ecology 171
succession can be seen in the Piedmont region of North Carolina. Early settlers of the area cleared
away the native oak-hickory forests and cultivated the land. In the ensuing years, the soil became
depleted of nutrients, reducing the soil’s fertility. As a result, farming ceased in the region a few
generations later, and the fi elds were abandoned. Some 150–200 years after abandonment, the climax
oak-hickory forest was restored.
In a stream ecosystem, growth is enhanced by biotic and abiotic factors. These factors include:
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Bare rocks exposed
to the elements
Rocks become
colonized by lichens
Mosses replace
the lichens
Grasses and
flowering plants
replace the mosses
Woody shrubs begin
replacing the grasses
and flowering plants
A forest eventually
grows where bare
rock once existed
FIGURE 6.13 Bare-rock succession. (Adapted from Tomera, A.N., Understanding Basic Ecological Concepts,
J. Weston Walch, Portland, ME, 1989, p. 67.)
Hundreds of years
Ability to produce offspring
Ability to adapt to new environments
Ability to migrate to new territories
Ability to compete with species for food and space to live
Ability to blend into the environment so as not to be eaten
Ability to fi nd food
Ability to defend itself from enemies
Favorable light