By Jamie Martin
Soil plays a vital role in crop growth, water movement, and environmental balance. However, scientists are increasingly questioning whether existing soil definitions reflect modern scientific understanding. A new proposal suggests that soil science should expand to match today’s discoveries.
The research was led by Dr. Aaron Lee M. Daigh of the University of Nebraska–Lincoln. Dr. Daigh serves as an associate professor in agronomy and biological systems engineering and is a recognized expert in soil science and hydrology.
“Soil science has enormous, untapped potential,” said Aaron Lee M. Daigh. “If we define our subject too narrowly, we artificially limit our science.”
Traditionally, soil is described as material that supports plants and shows clear layers formed over time. The new approach suggests that soil formation begins much earlier.
When natural forces such as climate, gravity and surface exposure begin shaping loose material, soil formation has already started. New sediments, even those without plants or animals, can qualify as soil from their first moments.
The proposal also challenges the idea of using a fixed depth to define soil. Instead of measuring soil by visual layers or root depth, scientists suggest focusing on how far surface forces cause movement of water, heat, gases, and dissolved materials. This changing zone is the true soil layer.
Below it, materials remain mostly unchanged. This idea can help improve decisions in irrigation, soil conservation, and environmental planning.
A third proposal includes icy materials as soil. Snowpacks and frozen surfaces on Earth, as well as icy bodies in space, experience environmental changes like soil. These icy surfaces can crack, flow, and respond to temperature changes. A new scientific term is used to describe soil that forms directly from ice rather than rock.
This expanded definition does not replace practical soil descriptions used in farming or government policy. Farmers and land managers can continue using simple definitions for daily work. The broader scientific definition supports research and helps scientists explore new areas of knowledge.
Clear definitions are important for food security, environmental protection, and climate research. They also help scientists understand Earth’s systems and prepare for future exploration beyond our planet.
By expanding what soil means, researchers aim to strengthen agriculture science, protect natural resources, and build knowledge that supports both Earth-based farming and future space missions.
Photo Credit: gettyimages-casarsaguru
Categories: National