Which term describes the layers within soil that may restrict water flow?

The term "soil horizons" accurately describes the distinct layers within soil that exhibit varying characteristics and may influence the movement of water. Soil horizons can differ in composition, texture, and structure, and these differences can create barriers to water flow. For instance, a dense clay horizon might restrict infiltration due to its low permeability, leading to water pooling above it or flowing laterally rather than percolating downward. Understanding soil horizons is crucial for septic system design, as the presence of restrictive layers can significantly affect the effectiveness of drainage and waste treatment.

Other terms, while relevant in soil science, do not specifically address the concept of layers that restrict water movement. Soil aggregates refer to clumps of soil particles that bind together, which affects structure and aeration, but do not define distinct layers. Soil texture encompasses the size and distribution of soil particles (sand, silt, clay) which influence water retention and drainage characteristics but does not refer to layers. Lastly, soil clumps is not a standard term used in soil science and does not effectively describe the stratification seen in soil profiles.