The soil fertility of the world may soon reach the point of jeopardizing global food security. A group of the country's top environmental scientists has authored a review paper about the tantamount importance of correcting the imbalance of soil depletion and replenishment.
Soil degradation and erosion – combined with damage to agricultural land from urbanization, as well as the expanding global population – are among the century's most urgent concerns for the international community, according to the researchers.
The "green revolution," which started in the late 1960s, considerably improved food production through concentrated farming that utilized agro-chemicals. The researchers however said that those principles and techniques would not be able to match the needs of the increasing population today — unless greater attention is given to soil fertility and soil preservation.
In a review of global soil fertility published in the journal Science, the research team said the most industrious farmland is a result of the domestication of wild soils produced by advance farming exercises. The challenge for these domesticated soils is preserving the quality of their wild inherited stock.
From 1970 to 2000, an area of agricultural plot the size of Denmark was developed and urbanized. In the next 20 years, an agricultural area the size of Mongolia – about 600,000 square miles – will be enveloped by city modernization, the scientists wrote.
Dr. Ronald Amundson – the study's lead author and a professor of environmental science, policy and management at the University of California, Berkeley – added that agricultural methods through the years have triggered the enhanced loss of soil through nutrient removal and erosion. This is one of the crucial game-changers for the extended, maintainable production of the soil — the living top layer of Earth.
One of the major challenges of future food security is maintaining the supply of artificial soil fertilizers — specifically potassium and phosphorus, which have to be extracted from reserves held in minerals and rocks.
The US reserve of phosphorus, for instance, accounts for just one to two percent of the total planet's reserves — and it could be exhausted in the next 20 or 30 years. This would no doubt generate political uncertainties and problems, in addition to the food crisis.
"We should be able to do this with soil. The nutrients lost can be captured, recycled and put back into the ground. We have the skill set to recycle a lot of nutrients, but the ultimate deciders are the people who create policy," Dr. Amundson concluded. "It's not a scientific problem. It's a societal problem."
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