Soil is one of the three major natural resources, alongside air and water. Soil is made up of three main components – minerals that come from weathered rocks, organic matter which is the remains of plants and animals that use the soil, and the living organisms that reside in the soil. A balanced soil contains 45% minerals, 25% air, 25% water and 5% humus.
These three soil components can be described as Chemical, Physical and Biological. The three are interlinked, with each having a significant impact on the functional ability of the other.
The Chemical component relates to nutrient composition, nutrient availability, base saturation and pH.
The Physical component relates to the structure and texture of the soil as well as the porosity, level of compaction and water holding. Structure means the arrangement of the particles and their strength of cohesion. Texture refers to the size of the particles within the soil,which are divided into sand, silt and clay.
The Biological components are the macro and micro fauna. These are responsible for the recycling of plant nutrients, disease suppression,drainage and the building up of organic matter.