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5 Soil Forming Factors − ClORPT

Cl = Climate

O = Organisms

R = Relief (or Topography)

P = Parent Material

T = Time

H = Humans ???

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Human Health

“Health is the level of functional and metabolic efficiency of a living organism. In humans it is the ability of individuals or communities to adapt and self-manage when facing physical, mental, psychological and social changes with environment”

- Wikipedia

Soil Health

“Soil health, also referred to as soil quality, is defined as the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans.”

- Natural Resource Conservation Service (NRCS)

Soil Tilth → Soil Quality → Soil Health

Only living things

can be “healthy”

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How can we increase soil health?

  1. Control traffic on soil
  2. Minimum tillage
  3. Manure use
  4. Cover crops
  5. Increase residue cover
  6. Crop rotations – increase crop variety (i.e. diversity)

Rule of Thumb – Anything that increases soil biological activity!

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The “living” SOM

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9/18/21

* 8,000 lb. elephant

Soil Flora or Fauna

Size (mm)

Numbers �(per g of soil)

Biomass �(lbs. / ac)

Elephants* �(per acre)

Viruses

0.0002

1010 – 1011

???

​

Bacteria & Archaea

0.001

109 – 1010

400 – 4,500

0.30

Actinomycetes

0.001

107 – 108

500 – 4,500

0.30

Fungi

0.008

10 – 103 m

800 – 13,000

0.89

Algae

0.013

104 – 105

10 – 500

0.03

Protista

0.050

102 – 106

20 – 300

0.02

Nematodes

1

101 – 102

10 – 300

0.02

Mites

0.5

1 – 10

1 – 500

0.03

Collembola

1

1 – 10

1 – 500

0.03

Earthworms

100

NA

50 – 3,500

0.23

TOTAL =

​

​

1,800 – 27,600

1.86

Who’s in our soil?

From Nature & Property of Soils (Brady & Weil), and other sources