is composed of aggregates of loose weathered rock and organic materials.

It is a semi-renewable type of resource because it is sustainable and can naturally be created by a significant amount of decomposed organic material.

It is a thin layer formed on top of Earth's surface, known as the —.

Soil is frequently called the "—" because it generally affects every part of the ecosystem. Varieties of organisms are found in the soil, including plants, rodents, earthworms. and microorganisms such as fungi, bacteria, and protozoans.

—, also called —, refers to the process of soil evolution under various biological, chemical, physical, climatic, and geologic factors.

The soil takes a long time to form in — regions than in wet and warmer regions.

refers to the chemical, physical, or biological breakdown of rocks and minerals at Earth's surface.

refers to the new minerals, organic matter, and decomposing materials ADDED TO THE TOP LAYER of the soil through wind, water, or ice, which have accumulated over a period of time.

— refers to the removal of soluble components from the top layer of the snil.

The materials lost are then eininted carried downwardi and are illeviated tdeposited to another layer by the percolating water.

Thus, the physical and chemical compositions of the newly accumulated materials and the parent material are altered

refers to the chemical breakdown of soil particles into degradation-resistant organic matter.

The accumulated materials are then carried away from the upper layer of the soil and are DEPOSITED in the LOWER HORIZONS.

With the help of plants and other organisms, the soill starts to take SHAPE ON ITS OWN through the process of —, with a more improved water-retention capacity and nutrient composition

The — is the preliminary solid material that makes up the soil.

refers to the location of the soil that influences the soil formation process.

It consists of factors such as the geological structure, the elevation of the sea level, the slope, and the configuration.

Processes such as soil formation and earthquakes affect the —, which then affects the soil formation.

refers to the weather that generally affects the transformation of the soil over a long period of time. It directly affects soil formation via rainfall (water), frost, and temperature theat from the sun).

such as animal inhabitants, vegetation, and human population greatly affect the process of soil formation.

The — of the soil is greatly influenced by the PHYSICAL AND METABOLIC ACTIVITY of animals and microorganisms. — influences the ACIDITY AND HUMUS content of the soil. Human activities such as construction, agriculture, or irrigation alto affect soil formation.

refers to the amount of time it took for the soil to develop.

also affects the humus content within the soil horizons.

The evolution of soil is greatly influenced by this factor.

refers to the sequence of VERTICAL SECTIONS from the surface down to the underlying bedrock.

The — consists of layers running parallel to the surface. These layers are called the —

The — is the succession of layers within a soil profile, which can be a few millimeters thin or a meter thick.

The — is the thin, topmost layer that contains accumulated organic materials.

It is approximately 0-2 inches in depth and undergoes intense biological activity.

It typically occurs in UNDISTURBED SOIL with lots of vegetative cover, such as a forest. It is usually BLACK OR DARK BROWN in color due to its high organic content.

The — is often referred to as the root zone or the topsoil.

It is a dark-colored layer due to the presence of humus.

It is approximately 2-10 inches thick and is called the ZONE OF ELUVIATION, where minerals are leached down the soil profile due to water infiltration.

The — is a light-colored layer usually present in forest areas.

It is the ZONE OF GREATEST ELUVIATION because the soil materials are leached from the and A horizons.

However, this is found only in OLDER AND WELL-DEVELOPED SOILS, and it usually gets RELOCATED to other horizons water infiltrates the soil and wash up this layer.

It generally occurs between A and B horizons. Note that in some soil profiles, the — is not used in the zonation process.

The — is commonly referred as the "ZONE OF ACCUMULATION" or "ILLUVIATION ZONE" because of the buildup of fine materials and mineral precipitates such as clay, carbonates, gypsum, and iron.

It is typically BROWNISH OR REDDISH in color because of the presence of iron hydroxides that leached from the surface.

The — is commonly referred to as the zone of parent material or substratum.

It is composed of the parent material underneath (bedrock) that has undergone various stages of weathering. It generally lacks the properties of O. A. and B horizons because it is less influenced by soil formation.

SOIL HORIZON