Soil Resources and Conservation

Soil is formed through the interaction of parent material (bedrock), climate, time, flora and fauna, and topography.
Composed of minerals, organic matter, water, and air, soil supports plant growth.
Soil texture, which refers to the size and proportion of particles, is a key characteristic.

Sand
- Largest soil particle type, visible to the naked eye.
- Composed of rock and hard minerals, primarily silicon dioxide.
- Enhances soil aeration and drainage; supports plant growth effectively.
Silt
- Intermediate size between sand and clay, carried by water to form fertile deposits.
- Non-plastic material, forming easily shaped mud when wet; blends smoothly with water.
Clay
- Smallest soil particles, measuring less than 0.002 mm.
- Derived from the chemical decomposition of rocks, forming cohesive, sticky textures when wet or dry.
- High water retention due to small spaces between particles, expanding when wet and contracting when dry.
- Organic clay exhibits high compressibility and strength when dry; commonly used in construction.
Loam
- A mixture of particles—such as 30% clay, 50% sand, and 20% silt—creating a balanced soil type.
- Labels like "clay loam," "silt loam," and "sand loam" indicate predominant particle types.

Represents the arrangement of different soil horizons, which vary by environment.
O Horizon
- Composed mainly of organic matter and humus, along with microorganisms.
A Horizon
- Comprised of minerals and humus; forms the top layer of soil with the O horizon.
E Horizon
- Light-colored layer with minimal organic material, involved in the processes of eluviation (fine component washing) and leaching (depletion of soluble materials).
B Horizon
- Known as subsoil, it is the zone of accumulation where minerals and nutrients gather.
C Horizon
- Features partially altered parent material, indicative of the soil's geological origin.
R Horizon
- Comprised of bedrock, including granite, basalt, and limestone, serving as the foundation for many soils.

One-third of the Earth's surface consists of land.
Arable Land
- Used for agricultural crops, temporary pastures, and fallow land.
Non-Arable Land
- Includes vineyards, orchards, and areas unsuitable for agriculture, such as grazing lands.

Farming, construction, and waste disposal significantly affect the quality and quantity of soil resources.
Conservation measures are essential for protecting soil for future generations.