This is the first lecture of the semester for my Soil and Water Conservation class (Spring 2013)

1. Welcome to CONS 405
Soil and Water Conservation

2. How do we know
what IL’s
vegetative cover
was like during
prehistoric
times?
Forest
Soil properties!

3. Slightly more than half Slightly less than half
Prairie soils Timber soils
Organic- rich A
horizon
Minerals are Minerals are
less weathered more weathered
From Brady and Weil, 2002

4. Green areas were dominated by
tall grass prairie vegetation.

5. Black areas were dominated by
forest vegetation

6. What is the
other primary
driver of soil
variation in
IL?

7. Glacial deposits cover most of Illinois
Most of these What is
deposits are under the
hundreds of glacial
feet thick! deposits?

8. Illinois Bedrock Geology

9. How many
of you have
been to the
WIU
Geology
Museum?
If you have been to
the museum,
what do you
remember :->?

10. The Geology Museum has a big
display representing geologic time
Millions of years ago
GEOLOGIC TIME
found in IL
these epochs
has ever been
No evidence of
IL bedrock geology

11. What is stratigraphy?

12. Engraving from William Smith's famous 19th century
monograph on identifying strata based on fossils
How do we know when a particular type of fossil formed?
Formation of the earth

13. Radiodating

14. Radiocarbon dating techniques, first
developed by the American chemist Willard
F. Libby and his associates at the University
of Chicago in 1947, are very useful in
deciphering time-related problems in
archaeology, anthropology, oceanography,
pedology, climatology, and recent geology.
What is pedology???

15. The amount of carbon-14 in a living organism
remains in balance with the amount of C-14 in the
atmosphere or some other portion of the earth's
dynamic reservoirs, such as the ocean.
Upon the organism's death, C-14 decays at a
known rate, and no further replacement of C-14
can take place.
The half-life of C-14 (~5730 years) limits the dating
period to approximately 50,000 years, although the
method is sometimes extended to 70,000 years.

16. Radioactive elements can be thought of as
"clocks within the earth's rocks” because
their consistent rates of radioactive decay
allow estimation of the time that has
passed since the rock solidified.
I am a mass
spectrophotometer!
Mass spectrophotometers are
used to quantify the abundance of
specific isotopes in a material

17. Magnetostratigraphy is another technique used to date
sedimentary and volcanic strata. The method works by
collecting oriented samples at measured intervals throughout
the section. The samples are analyzed to determine their
detrital remnant magnetism (DRM), that is, the polarity of
Earth's magnetic field at the time a stratum was deposited.
For sedimentary rocks, this is possible because when very fine-
grained magnetic minerals fall through the water column, they
orient themselves with Earth's magnetic field. Upon burial, that
orientation is preserved. The minerals behave like tiny compasses.
For volcanic rocks, magnetic minerals
that form as the melt cools orient with
the ambient magnetic field.

18. PRECAMBRIAN (4,500 to 543 mya)
We don’t know much about what happened during the Precambrian period
in Illinois. Cascade style volcanics and granite intrusions occurred 1.5 billion
years ago. Later, at 1.15 billion year ago the rifting (separating) of
continental plates created a weak zone along which the Mississippi River
later formed. This is the zone of the New Madrid Earthquake.
CAMBRIAN (543 to 490 mya)
Illinois was emergent for most of the
Cambrian period. Toward the end of
the Cambrian the sea came in and
deposited the sands and muds that
turned into the oldest dolomites,
sandstones and shales now found
in Illinois.

19. ORDOVICIAN (490 to 443 mya)
Illinois was covered by shallow seas during the Ordovician period. Marine
limestones and dolomites were deposited. In the late Ordovician, sands were
deposited. The St. Peter Sandstone, which formed from these sands, creates the
backbone for Starved Rock, Buffalo Rock, and Mattheissen State Parks.

20. There are 18
canyons at Starved
Rock State Park.
Most have
waterfalls.

22. SILURIAN (443 - 417 mya)
A shallow, tropical sea covered Illinois (then south of the
equator) during the Silurian. Corals, crinoids, and shelled
invertebrates flourished in the sea. In the late Silurian, the
first-known land plants (Cooksonia) and air-breathing animals
(millipedes and scorpions) appeared.

23. DEVONIAN (417 to 354 mya)
Deep stagnant basins covered Illinois during the Devonian
period. The sediments deposited in these basins turned into
thick black shale deposits, which are also found in Indiana
and Kentucky. Important biological changes occurred during
this period such as the development of fish and amphibians.
Shale gas reserves

24. MISSISSIPPIAN (354 to 323 mya)
Shallow seas covered Illinois during the Mississippian period.
More limestone was deposited forming the bluffs, caves and
karst topography of Western Illinois. The lead and zinc deposits
of NW Illinois, Iowa, and Wisconsin were formed at this time.

25. PENNSYLVANIAN (323 to 290 mya)
Tropical swamps dominated Illinois during the
Pennsylvanian period. These swamps formed the vast coal
deposits that now underlie 2/3rd of the state. Land plants,
spiders and insects were abundant as well strange swamp
creatures like the Tully Monster (state fossil).

26. IL has enormous coal reserves
that formed around 300 mya
Coal underlies 37,000 square miles
of Illinois -- about 65 percent of the
state's surface.
Illinois' coal reserves contain more
Btu's than the oil reserves of Saudi
Arabia and Kuwait.
Arguably the largest reserves of all
US states
~ half of the coal in the eastern US
~ 1/5 of the coal in the US

28. The Mazon Creek site is located 60 miles west of Chicago.
Spectacular fossils of Carboniferous forest plants such as horsetail,
fern, seed fern, lycophyte trees, and cordaites (a group of now-
extinct seed-bearing plants) are found here. The fossils formed in the
fine iron rich sediments that are the defining feature of Mazon Creek.
More than 300 animal species and 400 plants have been identified!

29. In most fossil deposits only the hard
parts of organisms (shells, bones,
teeth, etc.) are preserved. This
means that in most fossil deposits
only animals that have hard parts
are preserved.
Because of the unique conditions of
fossilization, Mazon Creek fossils
frequently have both hard and softer
parts preserved. In addition, many
soft-bodied organisms that do not
usually fossilize were preserved.
These factors mean that the fossils
from Mazon Creek provide scientists
with an extraordinary view of
biodiversity 300 million years ago.
Francis Tully ~ 1958

30. The Mazon Creek fossils are very unusual.
When creatures died, they were rapidly buried in
silty outwash. Bacteria that began to decompose the
plant and animal remains produced carbon dioxide
that reacted with iron in the groundwater forming a
very durable crust of siderite ('ironstone‘) – these
iron rich crusts remain today as 'casts' of thousands
of plants and animals.
Mazon Creek fossils are one of the most
concentrated and diverse assemblages of fossils
in the world.

31. Why aren’t there
any dinosaur
bones in IL?
IL bedrock geology

32. From ~1.8 million to ~12,000 years ago, massive sheets of ice
advanced across northern North America many times. This
period is known as the Pleistocene. Glaciers originating in
northwestern and northeastern Canada extended into parts of
Illinois during long cold periods. They melted back during
shorter warm phases of interglacial climate.

33. Over the last 750,000 years, ice sheets expanded into the
midwestern United States at least 4 times. The timing of the
earlier of these advances is not well known.
The last glaciation of the midwestern United States had its
maximum extent approximately 20,000 years ago.

34. Retreating Glacier

36. Depth of
loess cap
LOESS
silt sized glacial flour,
transported by wind,
deposited near rivers
Major reason
we have
fertile soils in
the Midwest

37. In northern China's Loess Plateau the edges of terraced fields
routinely collapse down steep gullies. Farming on this fragile
loess contributes to one of the world's highest erosion rates.

38. The hilly terrain of the Palouse region of the US is underlain by
a massive accumulation of loess—wind-blown, silt sized
particles. The soils are very productive but highly prone to
water erosion and annual soil loss >> 10 tons/ac is common.
?

39. Tundra vegetation established across IL as the glaciers retreated.
http://www.sciencefriday.com/news/030907/tree.jpg

40. Next, for several thousand years while glacial ice persisted in
southern Canada, Illinois was covered by boreal forest dominated
by spruce, fir and black ash. As the climate warmed, the ice
retreated and plants adapted to the boreal climate diminished. The
annual average temperature continued to rise, and by ~11,000
years ago, thick deciduous forest dominated by oak, elm, ash and
hickory covered Illinois.

41. How is it possible to determine vegetative shifts that occurred
thousands of years ago?
Lake sediment contains abundant fossil
pollen – commonly tens to hundreds of
thousands of pollen grains per cubic
centimeter of sediment.
Because pollen is released into the air
and transported long distances, the
assemblage of pollen in sediment is
representative of the vegetation from
the general region, not a single, small
area.
Palynologists (i.e., scientists who study
fossil pollen) can interpret a region’s
long-term vegetative history from the
layering of fossil pollen in sediment.
Some lakes even have annual layers of
sediment, like tree rings, that make it
possible to interpret short-term
vegetative/climate change.

42. Harlan's muskox first appeared in North America in the early
Pleistocene, around 500,000 years ago and lived all across
North America south of the late Pleistocene ice sheets. Its
fossils have been discovered at many sites in Illinois.

43. The Woolly Mammoth is one of three species of mammoth that inhabited North
America. It was common in Illinois 10-40,000 years ago. Discovery sites are
known throughout the state. It is thought that mammoths crossed the Bering
Straits less than 500,000 years ago. They were contemporaneous with humans
for thousands of years. Mammoths were large and heavily furred. They stood up
to 12 feet at the shoulder and had a large rounded dome and a sloping back.

44.  original tooth found in 1999

45. Mastodon bones are also common in Illinois. Three discovery sites are in
the Champaign-Urbana area—one is in east Urbana. Mastadons were
common in the Midwest 10,000 - 40,000 years ago. Large and hairy,
mastodons commonly stood 10 feet tall at the shoulder.

46. The vegetative shifts at
the end of Pleistocene
are likely to have been
very challenging for
Illinois’ megafauna.

47. The arrival of humans at the end of the Pleistocene
also created challenges for the megafauna.

48. In 1979, paleontologists made an exciting Mastodon State Historic Site
discovery at Kimmswick Bone Bed in Imperial,
Missouri—stone spear points with mastodon
bones. Clearly humans had visited Kimmswick
to hunt the herds of animals that came to
water at the spring-fed marsh located there.

49. About 8300 years ago, the climate in IL became substantially warmer
and drier, and within 500 to 800 years, most of the oak hickory
forests died out, except along stream banks. During this time, prairie
vegetation spread over much of IL.

50. An eastward extension of tallgrass prairie commonly called the Prairie
Peninsula has been studied for many years. One of the questions that has
long intrigued researchers is why this region was dominated by grassland
vegetation during the Holocene. Evidence suggests that annual
precipitation was normally more than enough to support trees.
One of the key factors is
thought to have been fire.
Annual dry periods in the
fall and early spring,
periodic extended
droughts, and the
flatness of the land all
promoted fire.
In addition, the
indigenous people are
thought to have regularly
set fires.

52. The hoof and grazing action of bison
also helped to maintain the prairie
Historical records suggest that the
eastern Bison herds that frequented IL
were much smaller than the vast western
herds.

53. How many bison skulls do
you think are in this pile?

54. Tallgrass prairie
once covered ~
170 million acres
of North America.
> 850 prairie plant
species just in IL

55. Summer views of Tallgrass prairie

56. Fall view
How tall was the Tallgrass prairie???
Big bluestem can grow 6-10’ tall!!

57. Just a different species of grass… right??

58. Much greater investment in roots!

59. Famous illustration of tall grass prairie species – above and below ground
16ft

64. Submit answers using WO before the start of class next Wednesday (1/23)
Reading questions for Prairie article
http://web.extension.illinois.edu/illinoissteward/openarticle.cfm?ArticleID=517
1) Describe (in your own words) some of the key geologic and climatic changes
that created the prairie dominated landscapes encountered by early IL settlers.
2) Which of the 4 main types of prairie ecosystems (INHS ecologists have
actually identified over 20 types of prairies in IL) would you most like to visit?
Describe some of the key characteristics of this type of prairie and explain why
you would like to visit it.
3) Describe some of the main factors that led to rapid conversion of most of IL’s
prairies to agriculture during the mid 1800s. Which types of prairies were the
last to be converted to agriculture? Why?
4) Identify a prairie preserve that can be visited within 50 miles of your
hometown. Use the web to track down some information about this preserve -
describe a few interesting things you would be see if you were to go visit it.

65. Quantitative problem
5a) Estimate the total # of acres of prairie in IL when it
became a state. (HINT ~ 55% of Illinois was prairie in 1818)
5b) If the amount of prairie in 1900 was 90% less than
when IL became a state, calculate the average # of
acres of prairie lost per year (i.e., between 1818 and
1900). Use any resources you like but explain all
assumptions.
Area of IL in square miles* 640 acres/square mile => ___ acres of prairie in 1818
90% of ___ acres of prairie in 1818 = ___ acres of prairie converted
___ acres of prairie converted / 82 years = ___ acres per year

67. Submit answers using WO before the start of class next Wednesday (1/23)
Reading questions for Grove article
http://web.extension.illinois.edu/illinoissteward/openarticle.cfm?ArticleID=489
1) Describe several reasons why early settlers tended to live in
or near groves of trees.
2) Why were the groves mostly isolated islands in a sea of
prairie and where did they tend to be located?
3) Describe what has happened to most of the groves in IL and
why the surviving groves look very different than they did 200
years ago.
4) Describe why it is challenging to restore groves and explain
your opinion regarding whether it is worth the effort to restore a
grove.

68. Until recently, one of the most useful sources of historical information
about pre-settlement Illinois ecosystems was largely overlooked.
1778
Survey records of the U.S. General Land Office (GLO) can be used to
reconstruct presettlement landscapes and vegetation patterns in IL and
many other upland regions of the United States.

69. General Land Office records are particularly useful to ecologists
because they contain detailed descriptions of pre-settlement tree
composition and timberland structure, as well as maps showing the
location and extent of former prairies, swamps, ponds, rivers,
streams, marshlands, and timberlands.
1818
Unlike historical narratives, GLO records provide us with quantitative
data that can be used to reconstruct baseline conditions.

70. The present-day Illinois River occupies only a small part
of an ancient river valley formed when the Illinois River
valley was the drainage outlet for much of the Upper
Mississippi River basin. The ancient river that occupied
the valley carried a much greater flow than the present
Illinois River.

71. Ice sheets during the Illinoian glacial advance (~300,000 to
132,000 years before present) blocked the ancient
Mississippi near Rock Island, Illinois, diverting it to its present
channel farther to the west, the current western border of
Illinois. The Hennepin Canal roughly follows the ancient
channel of the Mississippi downstream from Rock Island to
Hennepin, Illinois. South of Hennepin, to Alton, Illinois, the
current Illinois River follows the ancient channel used by the
Mississippi River.

72. Over geologic time, rivers
change courses many times

73. During floods, old channels
often become filled with water.

74. With greatly reduced flow and a smaller channel that occupied only a
small portion of the valley, the water flowing down the modern Illinois
river could not transport the sediment delivered by tributary streams,
resulting in the formation of alluvial fans and deltas near the mouths
of the tributary streams.

75. These fans and deltas created narrow constrictions that held
back water in the deeper channels and depressions in the flood
plain forming some of the bigger bottomland lakes in the valley.
Natural levees were also created along the riverbanks by
deposition of sediment from overbank flows during floods,
isolating old channels, sloughs, depressions, and lakes from the
main river. Over time these natural processes have created many
bottomland lakes along the Illinois River valley.

76. In 1908, the Illinois River fishery produced a
higher percentage of the U.S. harvest of
freshwater fish than any other North American
river. The river supported more than 2,000
commercial fishermen and produced an annual
commercial catch of 24 million pounds.

77. The Upper Mississippi Basin historically provided quality habitat for an
estimated 10 to 40 million beaver. These industrious animals built dams 400
to 500 feet apart on small streams; dams that, during storms, delayed the
movement of rainwater to the main channels.
Following Euro- American settlement, demand for beaver pelts and reduction of their
habitat drastically reduced North American beaver populations. While the beaver could
provide flood control in Illinois, not everyone would welcome back the beaver, as they
damaged trees, build dams and flood areas irrespective of human property rights.

78. Vast numbers of birds have used the Mississippi flyway for breeding
and/or wintering grounds for thousands of years.
Mallard ducks, which nest on islands or in grasslands adjacent to the
river are the dominant flyway waterfowl species. Eastern prairie
populations of Canada geese, snow geese, white-fronted geese,
gadwall, blue winged teal, green-winged teal, American widgeon,
American black duck, and northern pintail are also major species.
A number of land and predatory birds, such as the peregrine falcon,
Swainson’s hawk, eastern kingbird, summer tanager, and yellow
billed cuckoo also use the flyway.

79. Total number of species: 53,754+
Total number of extirpated species: 114
Total number of threatened/endangered species: 503