Unlock the Secrets of the Soil - A Campaign of the Natural Resources Conservation Service, U.S. Department of Agriculture
Image courtesy of Natural Resources Conservation Service, United States Department of Agriculture - www.nrcs.usda.gov
"We know more about the movement of celestial bodies than about the soil underfoot." - Leonardo da Vinci
Living in the soil are plant roots, bacteria, fungi, protozoa, algae, mites, nematodes, worms, ants, maggots, insects and grubs, and larger animals.
Science of Soil
Soil is made of about 45% minerals, 25% water, 25% air, and 5% organic matter.
Healthy soil has amazing water-retention capacity. Every 1% increase in organic matter results in as much as 25,000 gallons of available soil water per acre.
One teaspoon of healthy soil contains 100 million-1 billion individual bacteria.
All of the soil microbes in 1 acre/foot of soil weigh more than 2 cows.
Earthworm populations consume 2 tons of dry matter per acre per year, partly digesting and mixing it with soil.
What It Does
Healthy soil is key to feeding 9 billion by 2050
* Composition of soil: The Nature & Properties of Soils, page 17 (Nyle Brady, Ray R. Weil)
* Water holding capacity: Kansas State Extension Agronomy e-Updates, Number 357, July 6, 2012
* Bacteria in a teaspoon: Soil Biology Primer page c-1 (Elaine Ingham, Andrew R. Moldenke, Clive Edwards)
* Microbes weight: The Nature & Properties of Soil, page 458
* Earthworm population consumption: Earthworms - a Penn State publication by Sjoerd Duiker, Assoc. Prof. of Soil Management and Richard Stehouwer, Assoc. Prof. Environmental Soil Science
* Feeding people: The United Nations
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