Transcript Changes in the Community

Changes in the Community
No life in the BLAST zone: no
community, no soil.
Primary Succession
• Development of a
community that has
not supported life
before.
• Rocks, sand dunes,
volcanic islands
• Formation of soil
Primary Succession
• Development of a
community that has
not supported life
before.
• Rocks, sand dunes,
volcanic islands
• Formation of soil
Secondary Succession
• Secondary succession is the rebuilding of
an ecosystem after a disturbance that
damages or takes out all or part of the
existing community, BUT leaves the soil.
• Floods, tornados, fires
• Secondary succession, as with primary
succession, tends to result in the transition of a
community from the original pioneer species to
climax community.
• Climax Community: is a stable group of plants
and animals that is the end result of succession.
• The rate of secondary succession is much faster
than primary succession.
Succession in Water
Look familiar??
Which line represents primary succession? Secondary?
Limiting Factors for Population
Growth
• Density Dependent Factors- factors such
as predation, competition, availability of
food. Depends on how many organisms
there are in a certain area.
• Density Independent Factors- Factors
such as natural disasters- do not depend
on how many organisms there are in an
area.
• All biological populations experience
exponential growth (see graph below),
NOT linear growth.