In part three of this series on land, food and the future, I want to look at some of the possibilities for expanding food production without destroying the environment. (In case you missed them, here are parts one and two)
Earlier we ruled out a bunch of land types that aren’t currently used for agriculture:
Only half of usable land is used for farming, because the rest has forests on it. We’ve already agreed that we’re not going to cut the trees down – but can we produce food within the forest?
That’s what agroforestry is all about, and there are a variety of techniques. One is layer farming, which grows different crops in the trees and under the trees. For example, shade-grown coffee is a specialist kind of coffee farming which leaves the trees standing, and actually fetches a higher price because the coffee is excellent. Cocoa can also be farmed under the trees.
Or how about meat production? Cows are almost always seen in fields, but they’re just as happy in the woods. This is called silvopasture and it was very common in Europe and Asia in the past. It’s kind of a forgotten form of farming, but people are bringing it back. There’s a famous example in England at the Knepp estate, where the cows basically roam wild across the woodlands. This is less ‘efficient’ than feedlot beef and more expensive, so we’d still be looking at demand reduction, but it wouldn be better for wildlife and for climate change.
So we can produce food in forests. Anywhere else we might have missed?
How about deserts?
Sure. There’s the Sahara Forest Project in Jordan for example, where they have a pilot project. What they do is they place farms near the sea. They use solar power to take the salt out of the water, and use the water to grow food. That’s a working prototype with plans to build many more, but other companies, such as Sundrop Farms, are already using solar power and seawater to grow tomatoes in Australia, Somalia and a few other places. So we can grow food in the desert, at least in limited quantities . That doesn’t need to be lost land after all, and that’s really good news for the hottest parts of the world.
Not only can we grow food in the desert, we might even be able to restore the land and reverse desertification. Researchers in China have discovered that solar farms create their own micro-climate underneath them, and that this can help to reverse desertification. This is because the shade gives plants a chance in the inhospitable conditions. It prevents evaporation, and once plants get a foothold, they begin to rebuild soil out of desert sand. China has huge plans for desert restoration over the coming decades.
Okay, so we can produce food in forests and in deserts after all. Anywhere else?
Oh yes, the big one: the oceans.
Seaweed is such a versatile crop. We can eat it. We can feed it to animals. It can be used to make green fertiliser, or turned into biofuels. There are companies making seaweed-based plastics. Just this week I read about a company extracting nanomaterials from seaweed to make electric car batteries, which is a new one to me.
And there are many benefits to seaweed farming. It frees up land. It doesn’t need any fertiliser. It’s good for marine biodiversity. It locks up carbon. And when we think about the pressures on food production on land, isn’t the ocean the biggest possible solution?
In part 2 I wrote about eating less meat to free up the land that’s used to grow animal feed. What if we grew the animal feed in the oceans? Researchers have found that feeding certain kinds of seaweed to cows can reduce their methane emissions, which are a major greenhouse gas problem.
There are other ways to produce food without land too. Vertical farms often use aquaponics or aeroponics, where the roots of the plants are either in water or in a nutrient-rich mist. You can’t grow everything like this, but you can produce salad leaves, spinach, strawberries, herbs, and a range of other things. Farms like this can be placed right in cities, sometimes on rooftops, making food local and reducing travel distances. This is a very efficient form of farming that uses little water, very little land, and produces a high value crop.
And finally, this is perhaps the most science fiction sustainable solution I’ve ever come across.
These slightly odd looking food balls are not made of meat, or of plants. Or of clay. They’re made of a brand new food called solein, which is made of air and sunlight.
It sounds impossible, but it’s being done in Finland, where scientists have discovered a micro-organism that feeds on electricity. They feed it solar power, and it reproduces in a big steel vat that’s not very different from the brewing processes used to make yeast. Then you drain it and get a powder that’s almost pure protein, which can be used as an ingredient in bread or pasta or all sorts of other foods. It’s the first time that food has been made without land of any kind, and you can look up Solar Foods later to see how it’s done.
To conclude, we have looked at how the farmland available on earth is limited, and some attempts to grow more food have backfired and made things worse. But there are other things we can do that will get more food from the same land, and that expand food production in some interesting new ways.