SOIL FACTS – AND WHY SOIL IS IMPORTANT
Soil is the network of interacting living organisms within the earth’s surface layer which support life above ground.
The nutritional value of the food we eat is directly related to the health of the soil in which it grows (or what it eats grows).
Management of agricultural soils should consider the structural, biological and mineral health of the soil (not just N, P, K) to produce nutritionally-dense food.
Soil has varying amounts of organic matter (living and dead organisms), minerals, and nutrients.
An average soil sample is 45% minerals, 25%, 25% air, and 5% organic matter (less in degraded soils).
Carbon is a master variable within the soil that controls many processes, such as development of soil structure, water storage and nutrient cycling.
Soil high in organic carbon content enables better rainfall infiltration & retention – providing greater resilience to drought.
Every gram of soil organic carbon can hold up to 8 grams of water.
Soils are vulnerable to carbon loss through degradation, but regenerative land management practices can build soil and restore soil health.
Soil erosion within conventional agricultural practices can occur at rates up to 100 times greater than the rate of natural soil formation.
Natural processes can take more than 500 years to form 2 centimeters of topsoil.
Soil carbon takes three distinct forms: living carbon, labile carbon and fixed carbon.
– Living carbon takes the form of microbes, fungi, plant roots, nematodes, earth worms etc.
– Labile carbon in the soil comprises decomposing (dead) plant and animal material that is in a state of transition.
– Fixed carbon in the soil consists of stable compounds as humates and glomalins.
…Sequestered Carbon comprises the fixed carbon plus the total living biomass.
Soil stores 10% of the world’s carbon dioxide emissions.
Around 95% of our food is directly or indirectly produced on our soils.
Soil microbes have a symbiotic relationship with plants – plants provide sugars to microbes and microbes make nutrients bio-available for plants.
Living organisms in soil ultimately control water infiltration, mineral density and nutrient cycling.
Fungi and bacteria help break down organic matter in the soil and earthworms digest organic matter, recycle nutrients, and make the surface soil richer.
In a handful of fertile soil, there are more individual organisms than the total number of human beings that have ever existed.
Soil is one of the most complex biological materials on our planet.