Sunday, August 16, 2020

S.O.S. - Save Our Soils, Save Our Souls



One of the great ecological challenges of this century will be to save our stocks of farmland from soil degradation. While the degree of soil degradation varies from country to country, even Canadian farms are not immune.



Eight or nine years ago I did a couple of online courses on global food security. I found a couple of footnoted references in the assigned reading that steered me to couple of studies by top agronomists on the subject of soil degradation. It was pretty disturbing stuff.

In 2015 these reports were digested by the UN Food and Agriculture Organization (FAO) that issued a warning that the world might have no more than another 60 harvests before our soils became useless. That's a very awkward way of saying we are rapidly exhausting our productive farmland through intensive, industrial farming techniques and reliance on ever-increasing quantities of agricultural chemicals - fertilizers, herbicides and pesticides. We are stripping the essential carbon out of the soil.

Look at the map above.  Start with North America. There you'll see the US and Canadian grainbelt, much of it in red, i.e. very degraded. You'll find a similar situation through Central America, India, Sub-Saharan Africa and China.


Not only are we exhausting our soils, we're also depleting the aquifers that we drained so rapaciously to support the Green Revolution. That includes America's giant Ogallala aquifer that underlies eight states that comprise the Great Plains. In 2012, Harper's magazine featured an article, "Broken Heartland: The Looming Collapse of Agriculture on the Great Plains." I don't have a Harper's subscription at the moment but here's an excerpt.  Wait, wait, wait  - I tracked down the entire article here.

This isn't a North American problem. It's a global problem. It's partly agricultural but it is also many other things such as shifting and unpredictable (unreliable) precipitation patterns, droughts and floods, groundwater exhaustion, surface water contamination and more.

Guess what? I think I know how to fix this. I think I know how to rehabilitate degraded farmland. I think I know a way to do it at no to minimal cost. It might even be profitable. It would provide a tonne of new jobs. It is scaleable and would probably work in most parts of the world. It might even allow us to rehabilitate our beleaguered forests too. It might allow us to transform what we have so far overlooked as marginal land into productive farmland. I formulated this idea over a few years. There is plenty of science that supports it.  For the past several years, I've focused on finding flaws, pitfalls showing that it might not work. I've been looking. I haven't found anything. Nothing.

What I haven't found is someone to talk to. That would be someone in government probably at an ADM level who can take an hour or so to hear me out. An agriculture/environmental person. Know someone like that? Ask him/her to contact me at this blog or parksbmw@shaw.ca. Tell them it would help if they would familiarize themselves with the Sherman tank of WWII. Don't ask me to explain.

Why am I bringing this up today?  My inspiration comes from an item on CBC's web site, "With better soil, farmers can fight climate change, make agriculture more sustainable." It's about regenerative farming and how farmland can be used to capture carbon. It's all true. Boring but true.
David Burton, a soil scientist and professor at Dalhousie University in Halifax, said that over the years, intensive agriculture production methods — particularly tillage, which breaks up the soil in preparation for planting — have dramatically reduced the amount of organic matter in the soil. 
The result of less organic matter is that "the soil structure is being degraded, such that soils have difficulty holding water and resisting soil erosion, and they become less fertile," Burton said.

"That's making our agricultural production systems less and less productive, and some soils are becoming deserts and no longer able to produce food." 
In 2015, the Food and Agriculture Organization, a United Nations agency, calculated a finite number of growing seasons left if farming practices remain unchanged.

"Unless we improve our soil and soil management, we only have 60 harvests left," Burton said, referring to the UN's statement. "We'll only have 60 years to produce the food to support the world's population."
That's true, all of it. It's the model they're promoting that holds them back. There are better ways to do what they're trying to achieve.

UPDATE

To drive home how dire this predicament is, I just stumbled across a  New York Times article, "Global Warming Could Unlock Carbon from Tropical Soil."
Humble dirt could pack an unexpected climate punch, according to a new study published Wednesday in the journal Nature. An experiment that heated soil underneath a tropical rainforest to mimic temperatures expected in the coming decades found that hotter soils released 55 percent more planet-warming carbon dioxide than did nearby unwarmed areas. 
If the results apply throughout the tropics, much of the carbon stored underground could be released as the planet heats up. 
The thin skin of soil that covers much of our planet’s land stores vast amounts of carbon — more, in total, than in all plants and the atmosphere combined. That carbon feeds hordes of bacteria and fungi, which build some of it into more microbes while respiring the rest into the atmosphere as carbon dioxide. Many of these microbes grow more active at warmer temperatures, increasing their digestion and respiration rates.
In an attempt to forecast the future, ecologists began in the early 1990s building apparatuses to artificially heat soils. Such experiments in temperate and boreal forests have shown that carbon-rich soils almost always belch carbon dioxide when warmed. In 2016, a group of researchers estimated that, by 2050, soils could release so much of the planet-warming gas that it would be like adding the carbon emissions of a new country the size of the United States.
But that study left out the perpetually warm, mega-biodiverse tropics, where a third of all soil carbon resides.  ...For understanding soils’ contributions to climate change, the tropics “is a really important region” that “really hasn’t been studied,” said Margaret Torn, an ecologist at Lawrence Berkeley Lab in California, who was not involved in the study.

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