Soil, as mundane as it may seem, is essential to our survival. Without it we simply cannot grow food. In a world with an increasing population this is a resource we must look after. In the UK, if we carry on as we are now, it is reported, that our soils can only support 100 more harvests. World Soil Day on 5th December is an opportunity to raise awareness about the importance and threats to our soil.
Soil is very complex structurally, chemically and biologically. The problems facing our soils include:
30% of top soil globally is affected by acidification. Soils that are becoming more acidic are less able to grow crops. The causes of this include prolonged rainfall, application of too much ammonia based fertilisers, deforestation and land use changes. In the UK the Food and Agriculture Organisation (FAO) have assessed our soils for acidification and have rated them as poor.
Soils contain ¼ of the world’s biodiversity. Loss of biodiversity in soil slows decomposition, reduces nutrient levels and the amount of carbon dioxide soaked up and increases greenhouse gas release. In the UK the FAO have assessed our soils for biodiversity loss and have rated them as fair.
Soil is compacted by both machinery and livestock. Compacted soil reduces the ability of plant roots, water and oxygen to penetrate into the soil, reducing crop yields. In the UK the FAO have assessed our soils for compaction and have rated them as fair.
Contamination and Salinisation
Heavy metals, salts and pesticides are contaminating our soils. These come from atmospheric pollution, agriculture and flooding. They are poisonous to crops and reduce their yield and can make them unsafe to eat. In the UK the FAO have assessed our soils for contamination and have rated them as poor.
Soil Organic Carbon
Improved organic carbon levels in soils increases crop yield and water retention. This helps with flood mitigation and decreases the release of greenhouse gasses. In the UK the FAO have assessed our soils for organic carbon and have rated them as poor.
Globally 20 – 30 Gt (giga tonnes) of soil are lost to water erosion, 5 Gt are lost due to ploughing and 2 Gt are lost by being blown off the fields by wind. In the UK the FAO have assessed our soils for erosion and have rated them as fair.
Ultimately the long term threat for soils is rising sea levels and changing climate impacting on soil availability and also resulting in a range of the preceding factors mentioned above.
What to do
UK agriculture is waking up to importance of preserving our soils. As a consumer you can make choices that drive this transition by buying locally from a shop that you know sources from farms that work to the High Level Stewardship Scheme standards, involved with Natural England’s Catchment Sensitive Faming or is organic.
You can also participate in food waste and garden waste recycling schemes where the collected materials are either composted or digested to produce an output that can add nutrients and carbon back into the soil.
If you would like more information on how you can be more sustainable we have a host of experts at Credibly Green who can help you. Call us on 01746 552423 or email firstname.lastname@example.org