Soil Horizons
This topmost layer of soil is rich in organic material like decomposed plants and animals.
What is the O horizon (organic layer)?
These tiny organisms in the soil help break down organic matter, recycle nutrients, and improve soil health.
What are microorganisms?
This term refers to the level of acidity or alkalinity in soil, measured on a scale from 0 to 14, with 7 being neutral.
What is soil pH?
This soil texture is made up of the largest particles, feels gritty, and has good drainage but poor nutrient retention.
What is sand?
This is the main component of soil that provides nutrients, water, and a stable environment for plant roots.
What is soil?
This soil layer, just beneath the O horizon, contains a mix of minerals and organic material, often dark in color.
What is the A horizon (topsoil)?
This component is crucial for holding nutrients in the soil and affects its texture and drainage ability.
What are soil particles (sand, silt, and clay)?
Soil pH below 7 is considered this, which can affect plant nutrient availability.
What is acidic?
This soil texture contains the smallest particles and can become compacted easily, limiting water movement and air circulation.
What is silt?
Soil is made up of four main components: minerals, organic matter, air, and this essential element that provides moisture for plants.
What is water?
This horizon is called the "eluviation" layer and often has leached minerals from the layers above.
What is the E horizon (eluviation)?
This soil component helps to retain moisture and improves soil structure, often derived from decaying plant matter.
What is organic matter?
This pH level indicates neutral soil, where plants generally grow best.
What is pH 7?
This type of soil, often described as "ideal," supports most crops because it combines sand, silt, and clay in a balanced ratio.
What is loam?
This type of soil, which contains more silt than sand or clay, can hold moisture well but drains poorly.
What is silty soil?
This layer, also known as subsoil, is rich in minerals leached from above but lacks much organic material.
What is the B horizon (subsoil)?
This component of soil, making up about 45% of its volume, is composed of weathered rock particles and minerals.
What is mineral matter (or soil minerals)?
Soil with a pH above 7 is considered this, which can limit the availability of certain nutrients.
What is alkaline (or basic)?
This soil texture has the highest water-holding capacity due to its small particles but can become waterlogged and poorly aerated if not managed properly.
What is clay?
This "underground engineer" is a type of worm that aerates the soil, improving its structure and helping plants get more oxygen and nutrients.
What is earthworm?
This soil horizon, located beneath the O and A horizons, is characterized by the accumulation of leached minerals and clay, and is often referred to as the "zone of illuviation."
What is the B horizon (subsoil)?
This soil component, consisting of fine mineral particles and organic material, is crucial for nutrient retention and moisture holding, but too much can lead to poor drainage and soil compaction.
What is clay?
This type of soil pH is ideal for most crops, with a range between 6 and 7.
What is slightly acidic to neutral?
This tool, often represented as a triangle, helps determine soil texture based on the relative proportions of sand, silt, and clay in a sample.
What is the soil texture triangle?
Soil is home to more living organisms than there are humans on Earth, including billions of bacteria, fungi, and other microscopic creatures.
What is the soil ecosystem?