Secondary Succession
Sometimes ecological succession occurs in places where there is already soil, and that has
previously supported life. Secondary successionis the type of ecological succession that
happens after something destroys the community, but yet soil remains in the area. One event
that can lead to secondary succession is the abandonment of a field that was once used for
agriculture (Figure24.13). In this case, the pioneer species would be the grasses that first
appear. Gradually the field would return to the natural state and look like it used to look
before the influence of man.
Another event that results in secondary succession is a forest fire (Figure24.14and24.15).
Although the area will look devastated at first, the seeds of new plants are underground
and waiting for their chance to grow. Just like primary succession, the burned forest will go
through a series of communities, starting with small grasses, then shrubs, and finally mature
trees24.16. An orderly process of succession will always occur, whether a community is
destroyed by man or the forces of nature.
Figure 24.13: This land was once used for growing crops. Now that the field is abandoned,
secondary succession has begun. Pioneer species, such as the grasses, first appear and then
shrubs begin to grow ( 8 )
Climax Communities
Climax communities(Figure24.17)aretheendresultofecologicalsuccession. Incontrast
with the series of changes that occur during ecological succession, the climax community
is stable. The climax community will remain in equilibrium unless a disaster strikes and
succession would have to start all over again.