Professor Will Blake, Professor of Catchment Science and Professor Mark Fitzsimons, Professor of Environmental Chemistry.
You could say soil is one of the most underappreciated resources on the planet. However, that hasn’t always been the case.
In 1937, President Franklin D Roosevelt wrote a letter to all State Governors in the USA including the prophetic phrase, “the nation that destroys its soil destroys itself”. He recognised the risk of soil decline and degradation. But we have continued to plunder rather than preserve. The result is we now face a global soil crisis – however, it is one we have the knowledge to overcome.
Soils are currently facing a fight on many fronts. There is pressure from population growth. From intensive farming, and the damage that does to both soil and water quality. From land management and conservation policies. And, of course, pressure from climate change and extreme events like drought and flooding. There is also soil erosion, listed in a recent analysis by the United Nations as one of the key threats to the soil system.
It is claimed that the generation of 3 cm of topsoil takes 1,000 years. Yet some growers here in the UK have estimated they are losing 1 cm of topsoil from their land each year to erosion. Such a loss is obviously unsustainable, and unless swift action is taken, the quality of soil at our disposal will be degraded to such a degree that it no longer provides the food needed to support our population.
There are other risks too
Soil is a carbon sink, taking greenhouse gases out of the atmosphere and storing them. If our soils are damaged so is their ability to perform this essential task. And the knock-on effects of that – rising global temperatures, increased air and ocean pollution – would place an even greater strain on an already struggling planet.
As with so many aspects of human life, problems created on land can have wider effects. Soil erosion compromises food security but eroded soil can be washed into rivers, reservoirs and the ocean. Once there, the nutrients applied to maximise its benefits to crops can cause significant and lasting harm, affecting water security and ecosystem health.
Soil erosion can also compromise energy security. Soil coming off fields and hillsides turns into silt that can block hydropower dams.