Chapter 19
Cycles in Nature
Succession
 The gradual re-growth or
development of a community
of organisms over time
 Succession that occurs starting
on bare rock is called primary
succession.
 The first species to grow on the
rock are lichens and they are
called pioneer species.
Primary Succession
 Exposed rock
 Lichens
 Moss
 Ferns/grasses
 Shrubs
 Small trees
 Sometimes an area is
destroyed by natural disaster
or neglect and the original
plant community will re-grow
through secondary
succession.
Secondary Succession
 Weeds/crabgrass
 New weeds
 Small pines
 Hardwoods
Stable Community
 If an area of succession
experiences no changes then it
will eventually become a stable
community. This community will
reflect the climate and biome it
is in.
The Water Cycle
 The Carbon Cycle
Nitrogen Cycle