It’s a strange notion, but some experts fear the world, at its current pace of consumption, is running out of useable topsoil. University of Sydney professor John Crawford talks on the seismic implications soil erosion and degradation may have in the decades to come.
What happens if this isn’t addressed?
There are two key issues. One is the loss of soil productivity. Under a business as usual scenario,
degraded soil will mean that we will produce 30% less food over the next 20-50 years. This is against a background of projected demand requiring us to grow 50% more food, as the population grows and wealthier people in countries like China and India eat more meat, which takes more land to produce weight-for-weight than, say, rice.
Second, water will reach a crisis point. This issue is already causing conflicts in India, China, Pakistan and the Middle East and before climate change and food security really hit, the next wars are likely to be fought over unsustainable irrigation. Even moderately degraded soil will hold less than half of the water than healthy soil in the same location. If you’re irrigating a crop, you need water to stay in the soil close to the plant roots. However, a staggering paper was published recently indicating that nearly half of the sea level rise since 1960 is due to irrigation water flowing straight past the crops and washing out to sea.
Who will be impacted the most?
Soil erosion is most serious in China, Africa, India and parts of South America. If the food supply goes down, then obviously, the price goes up. The crisis points will hit the poorest countries hardest, in particular those which rely on imports: Egypt, for example, is almost entirely dependent on imports of wheat. The capacity of the planet to produce food is already causing conflict. A lot of people argue that food price hikes caused the Arab spring, and may even have contributed to the recent violence following the release of an anti-Islam film.
What about richer countries?
They will have to deal with more refugees fleeing from truly desperate situations. Then there’s the fact that this is happening at a time of economic difficulty in the West, with growing disparities across society and some people already having to resort to charity to feed themselves. The connection here with health is significant. Cheap food tends to be low in protein and high in carbohydrate, which is exactly the wrong balance for a healthy society. By reducing food to a mere commodity, we have created a system that is degrading the global capacity to continue to produce food, and is fuelling a global epidemic of diabetes and related chronic disease. Obesity in the US cost 150 billion dollars – 20% of the health budget – in 2008, the latest figures available, and this huge cost will rise as the broken food system takes its toll.
Why is the food system broken?
The big picture is that the amount of land per person has been shrinking over the last 100 years: we now have about a quarter of a hectare per person on the planet and we’re using half of the total land area on the globe for agriculture.
To be continued