1. What is Soil?

2. “ Soil is the hidden, secret friend, which is the root domain of lively darkness and silence” Francis Hole

3. “a living, dynamic system with organic and inorganic components
“a living, dynamic system with organic and inorganic components. Soil is a product of its environment and parent material”.

4. components By volume: By mass? 45% mineral 5% organic material
50% space (air/water)
By mass?
0% air
18% water
80% mineral
2% organic material

5. 1. The mineral component inorganic “mineral”: definition?
Primary: original components of earth crust
Secondary: new minerals made by weathering of earth’s crust
divided by particle size:
Sand, silt, clay

6. mineral make-up due to:
a. Parent Material
b. How resistant minerals are
c. Climate
d. “Age”

7. a. parent material
material on and in which soil develops

8. Examples of soil developing IN rather than ON parent material: 1
Examples of soil developing IN rather than ON parent material: 1. Apostle Islands

10. 2. Boundary Waters

12. 11 different parent materials …..

13. Regolith/bedrock: weathered rock

14. Alluvium: deposits on a flood plain from a river

15. Marine deposits: shell, reef and other “bits” formerly at bottom of ocean that have been uplifted

16. Lacustrine deposits: clay deposits originally laid down at the bottom of a lake; lake is no longer there

17. Example: glacial lakes in MN

20. Till: unconsolidated material deposited by glacial ice

22. Outwash: unconsolidated, sorted material deposited by meltwater from a glacier

26. Organic sediments: peat

28. Volcanic ash

29. Loess: deep deposits of silt that have been deposited by wind

31. Sand: beach sand, dune sand

32. Colluvium; material that moved downslope, as in a landslide

34. mineral make-up due to:
a. Parent Material
b. How resistant minerals are
c. Climate
d. Age

35. b. resistance of minerals
Soluble minerals are readily LEACHED from soil profile (Ca,Mg,Na)
Certain minerals tend to accumulate in soil
(oxides of Fe, Al, Si)

37. c. Climate
Amount of leaching
Rate of weathering

38. d. Age
Parent material is (usually) less influential in “older” (more highly developed) soil

40. 2. Organic Component Living (primarily decomposers)
Non-living (dead and all in-between stages of decomposition)

41. 3. The Space component
Soil pores
filled with air and/or water

42. A. soil air O2 CO2 N2 H 2O vapor (per cents by volume) (rh)
Above-ground atm <100%
Soil (grassland) atm %

43. B. soil water
Functions?
Polar molecule