OBJECTIVE FORESTRY

Detailed explanation-1: -The A horizon is the top layer of the mineral soil horizons, often referred to as ‘topsoil’. This layer contains dark decomposed organic matter, which is called “humus". The technical definition of an A horizon may vary between the systems, but it is most commonly described in terms relative to deeper layers.

Detailed explanation-2: -Topsoil is also called as A horizon. A horizon is the layer which is beneath the O horizon and above the E horizon. Topsoil is predominantly made up of humus and minerals. Humus is the organic matter formed due to the decomposition of dead plants and animals.

Detailed explanation-3: -Within the soil profile, soil scientists define zones called horizons. A horizon is a soil layer with distinct physical and chemical properties that differ from those of other layers.

Detailed explanation-4: -The layers of the soil are called horizons. The uppermost horizon is called the topsoil layer. The topsoil layer is a mixture of sand, silt, clay and broken down organic matter, called humus.