Soil composition

Science

Definition

Soil composition refers to the mixture of mineral particles (sand, silt, clay), organic matter (humus), water, air, and living organisms that make up soil. The relative proportions of these components determine soil type, fertility, and suitability for plant growth.

Examples

  • Sandy soil draining water quickly but holding few nutrients
  • Clay-rich soil retaining moisture but becoming compacted easily
  • Rich garden topsoil containing about 5% organic matter from decomposed leaves and organisms

Related Terms

Erosion and deposition Chemical weathering Mechanical weathering Soil contamination

Study This Concept

Practice soil composition with free review games in these units:

AP Environmental Science Unit 4: Earth Systems and Resources