What happens when we hit peak soy? Renewable resources running out

While using renewable substitutes for non-renewables is a great way to reduce our environmental impact, there’s no escaping the fact that renewables are finite. So what happens when we hit ‘peak soy’ or ‘peak corn’?

Of 20 renewable resources such as corn, rice, wheat and soy, 18 reached peak production in around 2006, an international group of scientists say. They say we can’t assume that natural resources can be swapped in and out to solve shortages, and that ‘renewable’ is not synonymous with ‘unlimited’.

Jianguo ‘Jack’ Liu, director of Michigan State University’s Center for Systems Integration and Sustainability, says this is a strong reason for integration - approaching sustainability problems holistically, rather than searching for a ‘one-for-one’ substitution to offset shortages.

“People often talk about substitution: if we run out of one resource, we can just substitute another. But if multiple resources are running out, we’ve got a problem,” said Liu.

Surprisingly, the researchers discovered not only that 20 resources had a peak year, but also that for 16 of these, the peak year lay between 1998 and 2008 - a narrow range in the history of humankind.

For instance, the maximum global growth rate in crop yields for soybeans was in 2009, for milk was 2004, for eggs was 1993 and for fish was 1988. The crop yield per area with corn, wheat, soy and rice on more than a quarter of the farming area around the world is stagnating or decreasing, US scientists say.

But Liu says there are several reasons why these peak years might be ‘synchronised’:

• Multiple resources such as land, food and energy are consumed simultaneously to meet the different needs of rapidly growing populations and diet changes worldwide.
• Producing one resource needs other resources - for example, food production needs land, energy and water.
• Producing resources creates pollution, which exacerbates resource shortages.
• Extracting less accessible resources results in an increased ecological and economic cost per unit extracted, thus lowering the availability of the remaining resources.

“Experts see opportunities for further increases in agricultural yield of about 1 to 2% per year due to better breeding techniques and genetically modified organisms, said Ralf Seppelt, a landscape ecologist with UFZ. “Mankind needs to accept that renewable raw materials are also reaching their yield limits worldwide.”

Liu says the situation isn’t hopeless, but means we can’t be simplistic when seeking solutions. He says we must acknowledge that all resources come with costs, and these costs may not be immediately obvious.

“The world is now tightly telecoupled. Tor produce one thing you need multiple resources often at distances, and we ignore that at our peril,” said Liu.

The results of the research were published in the international journal Ecology and Society and featured in the journal Nature’s Research Highlights.