What is soil?

Soil consists of four parts:

Mineral matter

Mineral part of soil consists of different size particles of sand, silt and clay.

Organic matter

  1. Fresh residues: the active, or easily decomposed, fraction.

  • Recently deceased microorganisms,

  • Insects,

  • Earthworms,

  • Old plant roots,

  • Crop residues,

  • Recently added manure

  1. Living organisms:

  • Archae

  • Bacteria

  • Actinomycetes

  • Fungi

  • Algae

  • Protozoa

  • Springtails

  • Mites

  • Nematodes

  • Earthworms

  • Ants

  1. Decomposing organic matter: The part of organic matter which is in a state of physical breakdown and biochemical transformation of complex organic molecules into simpler organic and inorganic molecules.

  2. Stabilised organic matter: Carbon that is protected from decomposition, through micro-aggregation, or an intimate association with silt and clay particles.

Water

H2O

Air

78,09% nitrogen; 20,95% oxygen; 0,93% argon; 0,04% carbon dioxide.