Http:// What does soil do for you ?

http://www.nh.nrcs.usda.gov/programs/images/soilfunctionsHQ.jpg

What does soil do for you ?

http://www.bgs.ac.uk/sustainablesoils/index.html

Total land used for agriculture ~ 12.4 billion acres

3.8 billion acres~ 10 % of earth’s land surface

8.6 billion acres~ 23 % of earth’s land surface

Science July 22 2005: Vol. 309. no. 5734, pp. 570 - 574

Most of the earth’s land surface is not well suited for agriculture

Green areas have few constraints

http://soils.usda.gov/use/worldsoils/mapindex/stresses.html

US Midwest is mostly green !

http://www.bgs.ac.uk/sustainablesoils/index.html

Soil is an archive of life

on earth!

Quantifying Biodiversity

Group Known Species

Estimated Total Species

Percentage Known

Vascular plants

220,000 270,000 81%

Algae 40,000 60,000 67%

Fungi 69,000 1,500,000 5%

Bacteria 3,000 30,000 10%

(Hawksworth, 1991)

Most live in soil

Even in places like deserts, where life may seem to be sparse, soil is full

of life!

The soil matrix presents its inhabitants with many challenges

Structural rigidity

Tortuous, loosely connected and highly constricted porosity

Low quality nutritional resources

Moisture fluctuations

As a result, most soil organisms are in a dormant state

waiting…

http://www.bgs.ac.uk/sustainablesoils/index.html

**

Maximum compaction is the goal !

(Brady and Weil, 2002)

What happened here ??

Karst regions in IL

Not a good place to build your house…

http://www.bgs.ac.uk/sustainablesoils/index.html

Soil participates in the hydrologic cycle

Agricultural run-off short-circuits the soil

Soil participates in the hydrologic cycle

water

water

SPRING

Tile drain

Runoff

Leaching

Gulf of Mexicohttp://www.greenlandsbluewaters.org/04_Glover.ppt

~40% of agricultural soils in IL have been tiled

Agricultural drainage short-circuits the soil

http://www.grida.no/climate/vital/graphics/large/12.jpg

Soil participates

in the C cycle

Gt = 109 t = Pg = 1015 g

C sequestration

http://www.bgs.ac.uk/sustainablesoils/index.html

Archaeological dig

Landfilling of wastes

http://www.bgs.ac.uk/sustainablesoils/index.html

Mining clay

THOMAS WADE, Peat Mining ,  1869

Modern peat mining in Canada

Peat mining in 19th century England

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

Trade-offs between soil functions

Science July 22 2005: Vol. 309. no. 5734, pp. 570 - 574