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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
