Solution:
The above statement is true.Humus is most abundant in topsoil. The topsoil layer of soil comprises organic matter, clay, sand, slit and other decomposed waste. The decomposed leftovers of plants and animals are called humus, and soil bacteria break them down into humus. For the bacteria to decompose, the remnants, oxygen and nutrition are necessary. More humus is found in the topsoil layer. The more nutrient-rich the topsoil would be. As a result, the topsoil is the soil layer where this occurs most frequently. Humus gives the soil the ability to absorb water and moisture. Therefore, soil's top layer contains more humus than its lower layers.
