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Last updated: January 15, 2013
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How do environmental histories of the Everglades help
future management? (Part 3)
Is the 1800s picture
typical of pre-drainage times?
Yes!
(Click on any of the images
below for a larger version.)
Soil cores from
northern Everglades (1920s)
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Subsampling from
a soil core
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Most of profile
is "sawgrass peat," with only a few layers of "sedimentary peat" (red),
reflecting climatic shifts.
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Sediment
cores suggest that conditions observed in the 1800s would also have been
typical throughout much of Everglades history.
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Pollen vs. age
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Modern pollen
analysis of cores from central Everglades (Room 3): -vegetation generally
stable until after 1900 AD
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| There are of course exceptions to the
stability. During regional or global climactic shifts, parts of the
Everglades apparently became drier. Vegetation changed predictably:
shallower water species replacing deeper water ones. Later, as the
climate returned to previous conditions, deeper water species also returned.
After regional droughts in the 16th century,
vegetation throughout the Everglades changed little until the 20th century.
The 1800's reconstruction of plant communities and extents appears typical
of the preceding 400 years--making it a reasonable goal for restoration
efforts. |
Post-Drainage Effects
| Detailed reconstruction of drainage history,
1880 to present, and of the associated landscape changes, provides an important
context for interpreting soil sediment information and for sharpening
the 1800s picture. |
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The
American Steel Dredge
A canal dredge
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(Click on the image
above for a larger version.)
Simplified timeline
of drainage events
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Putting the fill in place
for the Florida
East Coast Railroad
A likely block
to FL Bay circulation
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Next: Does restoration look feasible?
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