MercoPress. South Atlantic News Agency

Re-wilding agricultural land to avoid methane and exploding cows

Cows belch methane as they digest their fodder and, above a concentration of five per cent, methane becomes explosive.

By Gwynne Dyer – 'At least half the current agricultural land on the planet, more likely two-thirds of it, has to be re-wilded in order to restore the world’s principal carbon sink and to preserve the biodiversity on which the entire ecosystem depends.

“When I do a puzzle with my daughters, there is usually an elephant next to a giraffe next to a rhino,” said Prof. Ron Milo of the Weizmann Institute of Science. “But if I was trying to give them a more realistic sense of the world, it would be a cow next to a cow next to a cow and then a chicken.”

He didn’t mention the fact that the cows sometimes explode.

Well, not exactly, but, earlier this month (April 10), an industrial-scale dairy farm in Texas had a barn explosion that killed 18,000 cows. Cows belch methane as they digest their fodder and, above a concentration of five per cent, methane becomes explosive.

Apparently, nobody explained to the folks at the South Fork Dairy (near Dimmit, Texas) that proper ventilation will prevent methane from building up like that. However, explosions are the least of our cow problems. There are at least one billion cows in the world and the average cow produces a hundred kilos of methane per year.

That’s most unfortunate because methane is a powerful greenhouse gas, responsible for between a quarter and a third of the warming that is playing havoc with our climate today.

Moreover, more than half the agricultural land on the planet is used to feed not people, but all those cattle.

Early farmers domesticated cattle at least 8,000 years ago and even that had an impact on the planet. Over a few thousand years, the extra methane emitted by the relatively small number of tame cattle those farmers kept — probably only a few million — was enough to turn the climate trend completely around.

The normal pattern since long before human beings appeared on the planet has been a hundred thousand years of deep freeze, then a 10,000-year inter-glacial warm period like the present and repeat ad nauseam. The current inter-glacial started 11,900 years ago, so we should be sliding down into the next major glaciation by now, but we’re not.

The Ice Ages were cancelled permanently about 5,000 years ago. A few million extra cattle belching methane for 3,000 years put enough methane into the air to stop the cooling trend. Even before the Industrial Revolution, the average global temperature was a full degree Celsius higher than you would normally expect at this point in the cycle.

The fundamental issue is land use. Human beings have appropriated 40 per cent of the land surface of the planet for our agriculture (up from seven per cent in 1700), removing both the trees and most of the original wildlife and replacing them with our own crops and food animals.

If you count ‘managed’ forests, roads, buildings, ski-runs and everything in between, we actually control 75 per cent of the ice-free land surface. Much of the rest is bare rock, tending towards the vertical.

We have increased the mass of animal life on the land fourfold (mostly cattle), but removed two-thirds of the mass of vegetable matter (the forests). In fact, the bodies of living human beings now account for 36 per cent of the total weight of land mammals on Earth. Our farm animals account for 60 per cent, and wild animals for only four per cent.

This has to stop. At least half the current agricultural land on the planet, more likely two-thirds of it, has to be rewilded in order to restore the world’s principal carbon sink and to preserve the biodiversity on which the entire ecosystem depends. This doesn’t all have to happen right away, but it has to happen in the next 30 to 50 years.

At least half the current agricultural land on the planet, more likely two-thirds of it, has to be rewilded in order to restore the world’s principal carbon sink and to preserve the biodiversity on which the entire ecosystem depends.

As a transitional measure, we will feed the domestic animals with what’s being called food from the air (precision fermentation of selected bacteria, a rapidly developing technology), and give the farmland we used to grow their fodder on (half of all farmland) back to nature.

We can cut the emissions of our animals a bit by the clever use of food additives, but later most of them will have to go too. What will we eat instead? The plants that we grow on the remaining farmland and the thousand varieties of convincing meat, fish and vegetable substitutes that we can make with the astoundingly flexible fermentation technology.

And what about the two billion people who make their living from farming? That is a very large question, but most of them will have to find other employment within the next two generations.

Why haven’t you heard about this before? Because most of those who know it believe you aren’t ready to hear it yet. You’d think they’re mad. But in 10 or 15 years, almost everybody will know it.