Transcript Restoration

ECOLOGICAL RESTORATION
READINGS:
FREEMAN, 2005
Chapter 54
Pages 1277-1283
What is restoration ecology?
• It is the application of ecological
principles to return populations, species
or communities (ecosystems) to their
natural state.
• The act of restoration covers a wide
range of problems to be solved and
practices to be used.
Restoration of Populations or
Species
• When a local population or entire
species is showing signs of progressive
decline, then the act of restoration is
best described as recovery.
• When a local population or a large
number of populations have become
extinct, restoration requires
reintroduction.
Reintroduction of Populations
• The reintroduction of a population to an area
where it was once known to occur requires
more knowledge and effort than the act of
recovery.
• Two of the problems to be solved are:
* where to get the plants or animals to be
introduced?
* where to find the most suitable habitat for
introduction?
Recovery of a Population
• One of the unfortunate lessons learned
by conservation biologists is that
protection of plant and animal
populations by establishing preserves is
only a first step for many populations.
• Increasing the size of a declining or
small population requires a good deal of
knowledge about the biology of the
species.
Recovery Studies: Doing
Some Science
• Even in the highest quality preserves,
some species may not be maintaining
stationary or growing populations.
• Even populations that are stationary
may be small thus at high risk for
extinction.
• Determining best practices for recovery
efforts requires “doing some science.”
Recovery Study: Site
• Wolf Road Prairie is a 80 acre nature
preserve of which approximately 40 acres is
managed as prairie and savanna. Remainder
is marsh and shrub dominated “prairie”.
• Largest remnant of high-quality tallgrass
prairie on silt-loam soil in Illinois.
• 327 native taxa have been recorded as being
present in the area since 1973.
Recovery Study: Observations
• It is common practice to sow seeds of the
plant species as the major attempt at
recovery.
• It is possible to transplant adult plants as a
means of promoting recovery.
• Little is known about the relative success of
the seeding versus transplant methods for
promoting recovery of a plant species in a
prairie remnant.
Recovery Study: Experimental
Subject
• Great St. John’s
Wort is a perennial
forb that has a
complex life history.
• Only 1 plant was
known to exist at
Wolf Road Prairie in
1991; making it a
good subject for a
recovery project.
Qu i c k T i m e ™ a n d a
TIF F (Un c o m p re s s e d ) d e c o m p re s s o r
a re n e e d e d to s e e th i s p i c tu re .
Recovery Study: Experimental
Subject
• Great St. John’s Wort is
much less common in
Illinois than in Wisconsin.
• Its relative rarity and
fidelity to native plant
associations give it the
highest conservation
value (10).
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Recovery Study: Experimental
Subject
These are the various stages in the
reproductive life of Great St. John’s
Wort (Hyparicum pyramidatum).
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Life History Stages of Great
St. John’s Wort
Recovery Study: Question
Which life history stage of Great St.
John’s Wort is likely to have the highest
survivorship during the early years of a
recovery project?
Question: Which life history stage of Great St.
John’s Wort is likely to have the highest
survivorship during a recovery project?
Hypothesis: Transplants of adult plants are
more likely to survive than juvenile plants or
seedlings arising from stratified seeds.
Null Hypothesis: Survivorship of all life history
stages will be equal throughout the recovery
project.
Experimental Setup: Establish all three life
history stages of Great St. John’s Wort in the
UIC Greenhouse. Take to randomly selected
sites at WRP and transplant or sow seeds.
Record number of plants surviving for several
growing season.
Results:
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
• Conclusion: Recovery of Great St. John’s
Wort is best using vegetative stage year old
plants.
How effective is seeding as a
recovery method?
Seed s Sown at Wolf Ro ad Pra irie
N
u
100 0000
m
900 000
b
800 000
e
700 000
r
600 000
o 500 000
400 000
f
300 000
S 200 000
e 100 000
e
0
d
s
Great St John's Wort
998 000
760 500
676 083
345 391
118 575
163 998
199 3
199 4
199 5
199 6
199 7
416 667
358 333
199 8
199 9
200 0
Yea r Seed s Harvested
• Of the nearly 4 million seeds sown at WRP,
only 30 adult flowering plants were known to be
produced.
• Odds of getting from seed to flower were about
a million to one.
Restoration of Communities
(Ecosystems)
• The task of restoring communities
(ecosystems) is even more complex
than the task of recovery since the goal
is to enhance the survival of a larger
number of species.
• At UIC, we recognize three different
levels of community restoration.
Enhancement
• This level of activity focuses on only a few
native species that may require efforts at
recovery or reintroduction.
• Ecosystem level management techniques
place primacy on fire.
• An example is found at Woodworth
Prairie. Visit:
http://www.uic.edu/depts/bios/prairie/
Revitalization
• Focuses on a larger number of species
and modifications of the physical
environment.
• Native species are augmented by plants
and seeds from native plant gardens.
• Non-native species are targeted for
removal by cutting or herbiciding.
• Fire is used as a management tool.
• An example is Wolf Road Prairie. Visit:
http://www.savetheprairiesociety.org/
Reconstruction
• Works with land where native communities
have been replaced by non-native species.
• Efforts to reintroduce a large number of native
species and control populations of non-native
species.
• In addition to using fire, herbicides, mowing,
and cutting, hydrology returned to original
conditions.
• An example: Schulenberg Prairie. Visit:
http://chicagowildernessmag.org/issues/sum
mer2000/schulenberg.html
ECOLOGICAL RESTORATION
READINGS:
FREEMAN, 2005
Chapter 54
Pages 1277-1283