top of page

Surprising Soil Statistics

“Soil” never ceases to amaze. It is so much more than “dirt.” Here are some soil stats to ponder:

Icon design. ©The Earth & I
  • The National Cooperative Soil Survey has identified over 20,000 different kinds of soil in the US alone.

  • Carbon is incorporated into soil by the decomposition of organic matter. In fact, 48% to 58% of soil weight is made of carbon.

  • Soils hold more carbon than all the world’s vegetation.

  • It is estimated that the Earth has taken a 59% loss of available carbon in soil through the conversion of grasslands to crops.

  • Soil pH measures soil acidity or alkalinity. A pH of 7 is neutral, while less than 7 is acidic and higher than 7 is alkaline. The nutrition, growth, and yields of crops decrease with low soil pH.

  • An area is not considered to have soil if the surface is permanently covered by more than 2.5 meters (8.2 ft) of water. This depth is considered too deep for the growth of plants with roots.

  • Because soils are so varied, the lower boundary of soil has been arbitrarily set at 200 cm (6.6 ft).


Source: US Department of Agriculture, UN Environmental Statistics Division


Join Our Community

Sign up for our bi-monthly environmental publication and get notified when new issues of The Earth & I  are released!


bottom of page