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Glite Dictionary
A horizon

A horizon

8.4
Top layer of soil that is dark and rich with dead plant material
  • noun
  • /eɪ həˈraɪzən/
  • Specialized
translation icon : capa A
  • The A horizon in this forest soil is dark and rich with decomposed leaves.

Examples

  • Farmers often monitor the A horizon to assess soil fertility and potential crop yields.

  • Erosion can cause the A horizon to become thinner, reducing soil productivity.

  • The A horizon is vital for plant growth.

  • Farmers often test the A horizon for nutrients.

  • Farmers carefully examine the A horizon to ensure their crops receive the right nutrients.

  • The A horizon contains a wealth of organic material that supports healthy plant growth.

  • To improve soil quality, gardeners should enrich the A horizon with compost and organic matter.

Synonyms

topsoil
vsA horizon
14 2.8

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

is defined as the layer just below the outer soil with emphasis on humus
A-horizon
vsA horizon
  • Specialized
8.1

The top layer of soil that contains dark, rich plant material and where most roots grow

is the upper layer found just below the earth rather than stressing root zone
surface soil
vsA horizon
  • Specialized
3.4

The top layer of ground that has the most plant food

is the upper layer found just under the outermost soil rather than on top

Surface Forms

A horizon singular
A horizons plural

Morphology

a + horizon

Knowing 'horizon' signals a soil layer gives learners a strong clue that this refers to a type of soil horizon, but the 'A' is a technical label meaning the topmost, organic-rich layer rather than the indefinite article 'a'. The labeling convention is domain-specific and not fully derivable from the words alone, so comprehension is only partial without prior exposure.

Etymology

A horizon comes from people who study soil. They label the very top layer A and call each layer a horizon, so A horizon means the dark, rich 'top layer' of soil.