Soil and the Carbon Cycle

Soil respiration

A short-hand term for respiration by soil microbes.

Soil Organic Carbon (SOC)

The amount of carbon contained in the organic carbon compounds found in soil.

Soil Organic Matter (SOM)

The organic matter component of soil, consisting of plant and animal residues at various stages of decomposition, cells and tissues of soil organisms, and substances synthesized by soil organisms

Humus

A chemically stable type of organic matter composed of large, complex organic carbon compounds, minerals, and soil particles.

Charcoal (biochar)

Incompletely burned plant material that can remain undecomposed in the soil for decades to centuries

Humification

Formation of humus during the decomposition of organic matter in soils.

Plant root exudation

Oozing out of complex carbon compounds such as sugars, protein proteins through the pores of roots to the surrounding soil.

Mycorrhizal fungi

Fungi that have a symbiotic relationship with plants, living on and in plants' roots.

Active Soil Microbes

When soil microbes are carrying out their life activities such as reproducing, eating, metabolizing, biosynthesizing, transforming nitrogen compounds, decomposing dead organisms, humus and SOM, they need lots of energy; burning sugars via respiration provides that energy and releases CO2as a by-product.

Permafrost

Scientists are especially concerned about changes in rates of decomposition and soil respiration in permafrost which is a frozen soil found in cold latitudes.

Environmental resource pulse

A natural event of increased resource availability that happens suddenly, doesn't last very long, is rare but has a large magnitude.

Soil respiration

A short-hand term for respiration by soil microbes.

Carbon Sequestration

The process by which carbon is transferred from the atmosphere into plants, soil, and other organic matter through photosynthesis.

Decomposition

The breakdown of organic substances by microorganisms, releasing nutrients and carbon dioxide.

Soil Microbes

Microscopic living organisms found in soil, including bacteria, fungi, and protozoa, which play a crucial role in nutrient cycling and decomposition.

Soil Remediation

Enhancing or restoring the health of soil through various practices, such as adding organic matter, reducing tillage, and promoting biodiversity.

Soil Emissions

The release of greenhouse gases, especially carbon dioxide and methane, from soil due to microbial activity, decomposition, and changes in land use.

Conservation Tillage

Farming practices that minimize soil disturbance, maintain soil cover, and promote crop rotation to improve soil health and reduce erosion.

Soil Water Retention

The measure of a soil's capacity to hold and store water, essential for plant growth and microbial activity.

Sustainable Soil Management

Practices aimed at improving soil health by increasing organic matter content, promoting beneficial microbial activity, and enhancing nutrient cycling.

Soil pH

A measure of the acidity or alkalinity of soil, influencing nutrient availability and microbial activity.

Weathering

The physical breakdown of rocks and minerals into smaller particles, contributing to soil formation.