the making of illinois

79
Welcome to CONS 405 Soil and Water Conservation

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

TRANSCRIPT

Page 1: The making of Illinois

Welcome to CONS 405 Soil and Water Conservation

Page 2: The making of Illinois

Forest

How do we know

what IL’s

vegetative cover

was like during

prehistoric

times?

Soil properties!

Page 3: The making of Illinois

Prairie soils Timber soils

Organic- rich A

horizon

From Brady and Weil, 2002

Slightly less than half Slightly more than half

Minerals are

less weathered

Minerals are

more weathered

Page 4: The making of Illinois

Green areas were dominated by tall grass prairie vegetation.

Page 5: The making of Illinois

Black areas were dominated by forest vegetation

Page 6: The making of Illinois

What is the

other primary

driver of soil

variation in

IL?

Page 7: The making of Illinois

Glacial deposits cover most of Illinois

Most of these

deposits are

hundreds of

feet thick!

What is

under the

glacial

deposits?

Page 8: The making of Illinois

Illinois Bedrock Geology

Page 9: The making of Illinois

How many

of you have

been to the

WIU

Geology

Museum?

If you have been to

the museum,

what do you

remember :->?

Page 10: The making of Illinois

IL b

edro

ck g

eolo

gy

Millio

ns o

f years

ag

o

GEOLOGIC TIME

No evidence of

these epochs

has ever been

found in IL

Th

e G

eo

log

y M

use

um

has a

big

dis

pla

y r

epre

senting g

eolo

gic

tim

e

Page 11: The making of Illinois

What is stratigraphy?

Page 12: The making of Illinois

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?

Form

ation o

f th

e e

art

h

Page 13: The making of Illinois

Radiodating

Page 14: The making of Illinois

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???

Page 15: The making of Illinois

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.

Page 16: The making of Illinois

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

Page 17: The making of Illinois

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.

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 volcanic rocks, magnetic minerals

that form as the melt cools orient with

the ambient magnetic field.

Page 18: The making of Illinois

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.

Page 19: The making of Illinois

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.

Page 20: The making of Illinois

There are 18

canyons at Starved

Rock State Park.

Most have

waterfalls.

Page 21: The making of Illinois
Page 22: The making of Illinois

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.

Page 23: The making of Illinois

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

Page 24: The making of Illinois

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.

MISSISSIPPIAN (354 to 323 mya)

Page 25: The making of Illinois

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).

Page 26: The making of Illinois

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

IL has enormous coal reserves

that formed around 300 mya

Page 27: The making of Illinois
Page 28: The making of Illinois

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!

Page 29: The making of Illinois

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

Page 30: The making of Illinois

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.

Page 31: The making of Illinois

Why aren’t there

any dinosaur

bones in IL?

IL b

ed

rock g

eo

log

y

Page 32: The making of Illinois

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.

Page 33: The making of Illinois

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.

Page 34: The making of Illinois

Retreating Glacier

Page 35: The making of Illinois
Page 36: The making of Illinois

LOESS silt sized glacial flour,

transported by wind,

deposited near rivers

Depth of

loess cap

Major reason we have

fertile soils in the Midwest

Page 37: The making of Illinois

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.

Page 38: The making of Illinois

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.

?

Page 39: The making of Illinois

http://www.sciencefriday.com/news/030907/tree.jpg

Tundra vegetation established across IL as the glaciers retreated.

Page 40: The making of Illinois

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.

Page 41: The making of Illinois

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.

How is it possible to determine vegetative shifts that occurred

thousands of years ago?

Page 42: The making of Illinois

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.

Page 43: The making of Illinois

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.

Page 44: The making of Illinois

original tooth found in 1999

Page 45: The making of Illinois

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.

Page 46: The making of Illinois

The vegetative shifts at

the end of Pleistocene

are likely to have been

very challenging for

Illinois’ megafauna.

Page 47: The making of Illinois

The arrival of humans at the end of the Pleistocene

also created challenges for the megafauna.

Page 48: The making of Illinois

In 1979, paleontologists made an exciting

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.

Mastodon State Historic Site

Page 49: The making of Illinois

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.

Page 50: The making of Illinois

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.

Page 51: The making of Illinois
Page 52: The making of Illinois

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.

Page 53: The making of Illinois

How many bison skulls do

you think are in this pile?

Page 54: The making of Illinois

Tallgrass prairie

once covered ~

170 million acres

of North America.

> 850 prairie plant

species just in IL

Page 55: The making of Illinois

Summer views of Tallgrass prairie

Page 56: The making of Illinois

Fall view

Big bluestem can grow 6-10’ tall!!

How tall was the Tallgrass prairie???

Page 57: The making of Illinois

Just a different species of grass… right??

Page 58: The making of Illinois

Much greater investment in roots!

Page 59: The making of Illinois

16ft

Famous illustration of tall grass prairie species – above and below ground

Page 60: The making of Illinois
Page 61: The making of Illinois
Page 62: The making of Illinois
Page 63: The making of Illinois
Page 64: The making of Illinois

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.

Submit answers using WO before the start of class next Wednesday (1/23)

Page 65: The making of Illinois

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

Page 66: The making of Illinois
Page 67: The making of Illinois

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.

Reading questions for Grove article http://web.extension.illinois.edu/illinoissteward/openarticle.cfm?ArticleID=489

Submit answers using WO before the start of class next Wednesday (1/23)

Page 68: The making of Illinois

Until recently, one of the most useful sources of historical information

about pre-settlement Illinois ecosystems was largely overlooked.

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.

1778

Page 69: The making of Illinois

1818

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.

Unlike historical narratives, GLO records provide us with quantitative

data that can be used to reconstruct baseline conditions.

Page 70: The making of Illinois

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.

Page 71: The making of Illinois

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.

Page 72: The making of Illinois

Over geologic time, rivers

change courses many times

Page 73: The making of Illinois

During floods, old channels

often become filled with water.

Page 74: The making of Illinois

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.

Page 75: The making of Illinois

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.

Page 76: The making of Illinois

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.

Page 77: The making of Illinois

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.

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.

Page 78: The making of Illinois

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.

Page 79: The making of Illinois

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