Human activity is not a natural factor that influences soil formation. It is an external factor that can modify the soil properties and characteristics.

Weathering is the process of breaking down and altering the parent material into smaller particles and minerals, which eventually form soil.

The A horizon, also known as the topsoil, is the uppermost layer of the soil profile and is characterized by the accumulation of organic matter, nutrients, and microorganisms.

Leaching is the process of water moving through the soil profile and carrying dissolved minerals and nutrients, which can result in the loss of essential elements from the soil.

The USDA Soil Taxonomy is the soil classification system developed by the United States Department of Agriculture (USDA) and is widely used in the United States for soil surveys and land management.

Soil texture is determined by the relative proportions of sand, silt, and clay particles in the soil. Organic matter content can also influence soil texture, but it is not a primary determinant.

Prismatic soil structure is characterized by the formation of distinct, blocky or angular aggregates that are separated by vertical cracks or planes of weakness.

Wind erosion is the process of soil erosion caused by the action of wind, which can transport soil particles and cause significant land degradation.

The B horizon, also known as the subsoil, is characterized by the accumulation of clay minerals and other fine particles, which are transported from the A horizon by water movement.

Humification is the process of soil formation from organic matter, which involves the decomposition and transformation of plant and animal residues into humus, a dark, organic-rich material.

The USDA Soil Taxonomy is based on the concept of soil orders, which are the highest level of classification and are defined by the presence of diagnostic horizons or other soil characteristics.

Water erosion is the process of soil erosion caused by the action of water, which can transport soil particles and cause significant land degradation.

The R horizon, also known as the bedrock horizon, is characterized by the presence of bedrock or other hard material that is resistant to weathering and soil formation.

Andosolization is the process of soil formation from volcanic ash, which results in the development of soils with high organic matter content, dark color, and unique physical and chemical properties.

The FAO Soil Classification System is based on the concept of soil groups, which are defined by a combination of soil properties and characteristics.