Soil is essentially a non-renewable resource and a very dynamic system which performs many functions and delivers services vital to human activities and ecosystems survival.
Soil is fundamental for growing food. 90% of our food is linked to soil. Trees, shrubs and most other plants depend on the nutritions and water soil provides. On the reverse they provide us with oxygen and reduce CO2.
They filter rainwater into clean drinking water. Forest soil particularly can absorb huge amounts of water and store it. This way it prevents flooding and can overcome dry periods.
Soil is habitat for many living plants and animals. And there are more microorganisms in a handful of soil than there are people on earth.
Soil filters pollutants. Therewith it protects the groundwater, which is again the source of our drinking water. Forest vegetation keeps the soil humid and protects it from erosion.
Soil and Climate
The main reason for the change in our climate is the increased amount of carbon dioxide (CO2) in our air – healthy soil stores a lot of carbon dioxide and thus relieves the atmosphere.
The carbon dioxide cycle in the soil
Carbon dioxide gets into the soil in two ways. First, through the process of photosynthesis in plants. They absorb carbon dioxide from the air and release part of it to the soil via their roots. Second, and more importantly, through carbonaceous (organic) material (e.g. leaves and branches) that is deposited on the ground and converted into humus. As a result, a lot of CO2 is bound in humus. Humus is only slowly decomposed by microorganisms in the soil. This process releases the carbon dioxide again.
So the soil has a storage function for carbon dioxide, but it also releases it again – the carbon dioxide cycle. The main reason for the change in our climate is the increased amount of carbon dioxide (CO2) in our air – healthy soil stores a lot of carbon dioxide and thus relieves the atmosphere.
How soil is formed
Stones and rocks break in smaller parts due to the processes of weather. The impacts from frost, heat, water, and wind are called weathering. On the surface small cracks are formed, in which first plants start to develop. Their roots add to the job. When they dye, a thin humus layer is formed with the help of tiny organisms. This allows even more and over time bigger plants to grow. In this process, rocks are broken down more and more and the soil layer can grow.
From leafs to humus
Forest floor is a combination of humus, and mineral soil. Leafs are broken down by bacteria, fungi, and many critters like mites, springtails, slugs, woodlice, centipedes, and earthworms. In this way. Leafs are transformed into humus. There is no waste in nature. If the leaves fall from the trees in autumn, they are the basis of food for microorganisms. These soil organisms close the nutrient cycle in nature. Without them, the cycle of matter could not function and plant growth would not be possible.
Good soil, good storage
A good humus content in the soil ensures that more carbon dioxide is stored. This is favored by sustainable cultivation techniques and forms of cultivation with reduced tillage in agriculture.
The humid conditions of the peat soils make them ideal carbon sinks (natural stores) that counteract climate change. In addition to preserving biodiversity, this is another reason to preserve our moors.
Importance of earthworms
Earthworms are central when it comes to soil fertility. The tubes (biopores) they leave behind ensure that the soil is aerated – there is more space for plant roots and rainwater. So the earthworm ensures that the soil and the climate are better off.