Why are soils important?
Soil is our life support system. Soils anchor roots, hold water and store nutrients. Soils are home to earthworms, termites and a myriad of micro-organisms that fix nitrogen and decompose organic matter. We build on soil as well as with it.
Soil plays a vital role in the Earth’s ecosystem and without soil, human life would be very difficult.
Soil provides plants a foothold for their roots and holds the necessary nutrients for plants to grow. Soil filters the rainwater and regulates the discharge of excess rainwater, preventing flooding. It also buffers against pollutants, thus protecting groundwater quality.
Soil is capable of storing large amounts of organic carbon. It is the largest terrestrial store of carbon. On average, the soil contains about three times more organic carbon than the vegetation and about twice as much carbon than is present in the atmosphere [source]. This is of particular importance in efforts to mitigate climate change. Carbon can come out of the atmosphere and be stored in the soil, helping to re-balance the global carbon budget.
Soil provides people with some essential construction and manufacturing materials: we build our houses with bricks made from clay and we drink coffee from mugs that are essentially baked soil (clay). Water is served in a glass made from sand (silicon dioxide).
Rocks and minerals come to mind as the basis of soil material, however the soil also hosts a great deal of living organisms. The biodiversity of visible and microscopic life which uses the soil as their home is vast. The soil is one of the planet’s great reservoirs of undiscovered microorganisms and therefore genetic material which can become the basis of other scientific research such as developing new medicines.
Soil is also an archive. It presents a record of past environmental conditions by storing natural artifacts from past ecosystems like pollen. Many artifacts from human history are also stored underground, which archeologists carefully uncover and use to understand how civilizations have evolved.
Soil functions are general soil capabilities that are important for many areas of life including agriculture, environmental management, nature protection, landscape architecture and urban applications. Six key soil functions are:
- Food and other biomass production
- Environmental Interaction: storage, filtering, and transformation
- Biological habitat and gene pool
- Source of raw materials
- Physical and cultural heritage
- Platform for man-made structures: buildings, highways