1. Composition:
* Mostly undecomposed plant material: This includes leaves, twigs, needles, and other organic debris.
* Varying degrees of decomposition: The litter may range from fresh and recognizable to partially decomposed and fragmented.
2. Physical Properties:
* Loose and porous: The litter horizon has a high air content and water infiltration due to its open structure.
* Variable thickness: The depth of the litter horizon can vary depending on the type of vegetation, climate, and soil conditions.
* Color: The color is often brown or yellow, but can vary depending on the type of plant material and degree of decomposition.
3. Chemical Properties:
* High organic matter content: The litter horizon is rich in organic carbon, which provides nutrients for plant growth.
* Slightly acidic: The decomposition of plant material often releases organic acids, leading to a slightly acidic pH.
4. Biological Activity:
* Abundant decomposers: The litter horizon is teeming with microorganisms like bacteria, fungi, and invertebrates, which break down the organic matter.
* Habitat for various organisms: Many small animals like insects and worms live in the litter horizon, contributing to its decomposition.
In summary, the surface litter horizon is a distinct layer of soil characterized by undecomposed plant material, high organic matter content, a loose structure, and abundant biological activity. It plays a crucial role in nutrient cycling and soil formation.
