- Soil is the uppermost layer of Earth's crust, supporting plant growth and containing organic and inorganic materials.
- The study of soil is known as pedology.
- Soil formation is influenced by factors such as parent material, climate, organisms, topography, and time.
- Soils are classified based on their texture, composition, and fertility.
- Globally, soils are categorized into major types such as alluvial soil, black soil, red soil, laterite soil, desert soil, and mountain soil.
- Alluvial soils are found in river basins and plains, characterized by high fertility and fine texture.
- These soils are widespread in regions like the Indo-Gangetic plain and the Nile valley.
- Black soils, also known as Regur soils, are rich in clay and ideal for cotton cultivation.
- Black soils are found in regions like the Deccan Plateau in India.
- Red soils get their color from the presence of iron oxide and are found in tropical and subtropical regions.
- These soils are common in areas like Southern and Eastern India and parts of Africa.
- Laterite soils are rich in iron and aluminum but poor in fertility due to leaching.
- Laterite soils are found in humid tropical regions like India, Brazil, and Indonesia.
- Desert soils are sandy, poor in organic matter, and have high salinity.
- These soils are common in arid regions like the Sahara Desert, the Thar Desert, and the Arabian Peninsula.
- Mountain soils are found in high-altitude areas and vary in composition due to climate and vegetation.
- Mountain soils are typical in regions like the Himalayas, the Andes, and the Rockies.
- Peaty soils, rich in organic matter, are found in waterlogged areas like Kashmir Valley and parts of Scotland.
- Marshy soils are found in wetland areas and are rich in humus but poor in drainage.
- Soil texture depends on the proportion of sand, silt, and clay particles.
- Soil structure refers to the arrangement of particles into aggregates.
- Fertile soils typically have a balanced pH and adequate nutrients like nitrogen, phosphorus, and potassium.
- The FAO soil classification system is widely used for categorizing soils worldwide.
- Soil degradation, caused by deforestation, overgrazing, and erosion, is a significant environmental issue.
- Soil conservation methods include terracing, contour plowing, and crop rotation.
- The USDA soil taxonomy classifies soils into 12 orders, including Alfisols, Mollisols, and Oxisols.
- Alfisols are fertile soils found in temperate forests.
- Mollisols, rich in organic matter, are typical in grasslands like the Great Plains.
- Oxisols are highly weathered soils found in tropical regions.
- Soil erosion, caused by wind and water, reduces soil fertility and productivity.
- Practices like afforestation and mulching help prevent erosion.
- Soil profiles consist of distinct layers called horizons, including the O, A, B, and C horizons.
- The O horizon is rich in organic matter, while the A horizon is the topsoil.
- The B horizon is the subsoil, and the C horizon consists of weathered parent material.
- Leaching occurs in humid regions, washing nutrients from the topsoil.
- Salinization is the accumulation of salts in the soil, common in arid regions.
- Soils in coastal areas often suffer from saltwater intrusion.
- Soil fertility is influenced by factors like organic content, pH levels, and moisture.
- Soil testing helps determine the appropriate use of fertilizers and amendments.
- Humus, the organic component of soil, improves fertility and water retention.
- Soils are crucial for agriculture, forestry, and sustaining biodiversity.
- Wetlands act as natural water filters and are often associated with fertile soils.
- Urbanization and industrial activities lead to soil contamination with heavy metals and chemicals.
- Soil plays a key role in the carbon cycle by storing organic carbon.
- Climate change affects soil properties, including temperature and moisture content.
- International initiatives like the Global Soil Partnership focus on soil health and conservation.
Category