What is leaf litter primarily composed of?

Leaf litter is primarily composed of decaying leaves. This organic material plays a critical role in the ecosystem as it contributes to soil health, provides habitat and food for various organisms, and helps in moisture retention. As leaves fall and accumulate on the ground, they start to decompose due to microbial activity and the actions of other decomposers like insects and fungi. This decomposition process is essential for nutrient cycling, enriching the soil with organic matter and promoting plant growth.

The other options do not represent the primary components of leaf litter. Plastic waste, for instance, is synthetic and does not decompose in the same natural manner, while grass clippings and wood chips are different types of organic materials but are not the primary constituents of leaf litter. Grass clippings are more typically associated with lawn care and maintenance, and wood chips are often used as mulching material rather than being part of the natural leaf litter found under trees.