The Science of Soils Objectives Methods Glossary References Data Sheets Questions Menu . . The Science of Soils Introduction Soil is a natural product that forms due to the action of weathering rock as well as the actions of the climate and living organisms. This classifies soils as a living system, just the same as the ocean or a forest would be considered a living system. Soils differ in structure, color, texture, nutrient content and other physical characteristics due to the environment in which they form and the items which they are composed of. In nature, soils form in layers which when examined is called a soil profile .
Scientists study soil profiles by removing a thin, vertical sample of soil.
Each distinct layer in the profile is called a horizon . Each horizon has its own physical characteristics including texture, color, and nutrients. Most soils have five major horizons. At the front desk you will find samples of each horizon type. Examine these samples and look for their recognizable traits.