Soil is the thin layer of material covering the earth’s surface and is formed from the weathering of rocks. It is made up mainly of mineral particles, organic materials, air, water and living organisms—all of which interact slowly yet constantly.
Soil minerals are produced from rocks (parent material) through the processes of weathering and natural erosion. Water, wind, temperature change, gravity, chemical interaction, living organisms and pressure differences all help break down parent material. The types of parent materials and the conditions under which they break down will influence the properties of the soil formed.
The pages here provide some basic information about the parent materials and climate setting within which the soils of Tonga have formed.
Information about land use and and major soil related projects is also provided.