Nutrients in soils are one of the most essential components that determine land productivity and consequently availability of food resources.
The balance between these components, or more precisely the presence of carbon, nitrogen and phosphorus in sufficient quantities, is strongly determined by availability of water.
A team of scientists, led by Manuel Delgado-Baquerizo from Universidad Pablo de Olavide in Sevilla, Spain, conducted a detailed study on the influence of climate change on nutrient availability. The study published in the latest issue of Nature indicates that increase in aridity will be the main cause of reduced land productivity and it will potentially threaten the global food supplies.
The study was conducted in 224 dryland sites located in all continents except Antarctica, covering regions with various ecosystems. Since 2009, the scientists have been gathering data that helped them develop a statistical model, which predicts the behavior of nutrients in soil as climate changes, temperatures increase and scarcity of water becomes more apparent. The most striking finding was that the balance of nitrogen and phosphorus, two of the probably most essential for plant growth nutrients, will be severely disrupted. As land becomes drier, nitrogen availability will decrease, while phosphorus will increase.
The authors point out that although these two are the key components of fertilizers, the proportion and natural availability of nitrogen and phosphorus are extremely important, and artificial additives might not be able to restore the soil productivity.
Currently, around one-fifth of the world’s population occupies drylands. Low levels of moisture are characteristic for roughly 40% of the earth surface, and yet these areas provide most of the essential food supply. People, who strongly depend on the productivity of these lands for fuel, crops and livestock grazing, will be most effected up to a point that their lives could be in danger.
In addition to this, lack of moisture, nutrients, and consequently vegetation, will result in increase in dust storms, which will pollute the air and increase the cases of lung and respiratory diseases.
We can only hope now that such studies are made publicly available and serve as a reminder and a wake up call not only to governmental officials and policy makers, but also to all of us, who should join forces in the fight against climate change.
