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A-horizon

A-horizon

8.1
The top layer of soil that contains dark, rich plant material and where most roots grow
  • noun
  • Specialized
translation icon : capa A
  • The A-horizon is often the most fertile part of the soil, supporting lush plant growth.

Examples

  • Farmers test the A-horizon to understand nutrient levels before planting crops.

  • Erosion of the A-horizon can severely impact agriculture productivity in a region.

  • The A-horizon is crucial for plant growth.

  • Farmers often test the A-horizon for nutrients.

  • The A-horizon is the uppermost layer of soil where plants absorb most of their nutrients.

  • Farmers rely on the A-horizon for its rich organic material to grow healthy crops.

  • Healthy gardens often have a thick A-horizon that supports vibrant plant life.

Synonyms

topsoil
vsA-horizon
14 2.8

The upper layer of soil rich in nutrients where most plants grow roots

is a specific technical label for that same upper layer
A horizon
vsA-horizon
  • Specialized
8.4

Top layer of soil that is dark and rich with dead plant material

is the same meaning but written with a hyphen
surface soil
vsA-horizon
  • Specialized
3.4

The top layer of ground that has the most plant food

is the upper soil layer often located just below the surface
soil horizon
vsA-horizon
  • Specialized
6.3

A layer of earth that is different from the layers above and below it

is the specific topmost layer among those distinct soil layers

Surface Forms

A-horizon singular
A-horizons plural

Morphology

A-horizon = horizon (semi-transparent) = A + horizon

The letter 'A' is an arbitrary alphabetical label attached to the soil 'horizon' (layer); the combination signals a specific labelled soil layer but requires domain knowledge of soil-horizon classification.

Etymology

A-horizon breaks into A- meaning the first or 'top' part and horizon meaning a 'layer' or 'band', like the horizon line where land meets sky. So the A-horizon is the top layer of soil rich in organic material and humus where most plant roots grow.