Salted crops seen as powerful tool to combat climate crisis

Salted crops seen as powerful tool to combat climate crisis
Salt has preserved everything from fish to cucumbers over the years, so why not carbon-containing crops as well?
Salt has preserved everything from fish to cucumbers over the years, so why not carbon-containing crops as well?
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Salt has preserved everything from fish to cucumbers over the years, so why not carbon-containing crops as well?
Salt has preserved everything from fish to cucumbers over the years, so why not carbon-containing crops as well?

Salt is one of the oldest and most famous preservatives around. But could it be used to preserve carbon deep underground for thousands of years? Researchers believe it can, and that it just might offer a way forward in combating the atmospheric carbon levels that are leading the planet into an unprecedented climate crisis.

With greenhouse gas emissions like carbon dioxide continuing to increase, and climate feedback loops partially caused by these emissions accelerating, finding ways to suck carbon out of the air is more crucial than ever. The problem is that direct air capture (DAC) technologies such as the quick and efficient one developed by researchers from Tokyo Metropolitan University last year, can be quite costly to build and maintain.

For example, at the world's largest carbon capture plant, which is slated to open in Wyoming this year, grabbing one tonne of carbon out of the air will cost US$600, although the developers of that project hope to eventually bring the cost down to the hundred-dollar range. Even at $100 per tonne, considering that we need to remove nearly one billion tonnes of carbon from the atmosphere per year to meet current climate goals, the cost will be mighty.

So that has left scientists scrambling to find other ways to get the carbon out of the air in a more cost-effective way. Earlier this year, scientists at MIT proposed a relatively inexpensive way to remove carbon from the world's oceans so that they could soak up more carbon from the atmosphere, and last year chemists at the University of California Berkeley proposed using a cheap material called melamine to grab carbon from smokestacks and tailpipes.

Another affordable way to capture carbon from the air is through what's known as agro-sequestration. While it might sound like something a petulant tween might do when having a bad day, the technique actually involves growing crops (such as certain grasses) that sequester carbon, and then burying those crops deep in the ground. The problem is that when bacteria starts to break down those crops, the carbon will be re-released into the atmosphere.

Seeking to overcome this hurdle, scientists at Berkeley have come up with a simple solution: salt. By first drying the crops and then burying them in biomass pits lined with two-millimeter-thick layers of polyethylene, then adding salt, the crops could hold onto their carbon store for centuries underground.

"There are significant questions concerning long-term sequestration for many of these recently popularized nature- and agriculturally-based technologies," said Harry Deckman, co-author of a new study on the method. "The agro-sequestration approach we’re proposing can stably sequester the carbon in dried salted biomass for thousands of years, with less cost and higher carbon efficiency than these other air-capture technologies."

Unlike DAC technologies, the researchers say their solution would cost only about $60 per tonne of captured and sequestered carbon dioxide. What's more, the process would be carbon-negative, as for each tonne of dry biomass, two tonnes of carbon dioxide could be sequestered.

The team put together a list of high-productivity plants, and say that the majority can be grown on marginal farmland, most of which isn't currently being used to grow crops. They also say that a 1-hectare pit could hold material from 10,000 hectares of biomass. Using those calculations, the researchers say that it would take only one-fifteenth of the world's croplands, forests, and pastures to sequester half the world's greenhouse emissions.

"To remove all the carbon that’s produced would require a lot of farmland, but it’s an amount of farmland that is actually available," said Yablonovitch. "This would be a great boon to farmers, as there is farmland that is currently underutilized."

The study has been published in the journal, PNAS.

Source: UC Berkeley

Growing crops requires lots of water. This wont work East of Mississippi which is usually in a drought cycle with lake mead and lake powell almost dry.
Team this up with large algae ponds,which have phenomenal growth rates. Dry the algae and preserve with salt along with other biomass.
Burn bio-mass in charcoal ovens and the charcoal produced is not bio-degradable.
The heat can be harvested for???
No salt required.
Captain Obvious
No thanks. Biochar works better and is beneficial to the soil.
Biomass pits lined with polyethylene and salt? There has to be an easier way to deal with CO2. Moreover, methane release might end up being the bigger issue down the road.
If you are burying a ton of biomass how does this equate to two tons of carbon? This needs explaining.
I expect that land-based biomass is too desperately needed for maintaining soil quality. You'd be depleting soil quality via this method. Also, those buried bags of salty vegetation will be a cost for future generations. When the bags fail, you'll have salt flowing into the water table. I can imagine future generations screaming: "What idiot thought this was a good idea????"

If we're facing an absolute immediate crisis of global warming causing more global warming, this might be one valid temporary solution, but otherwise this idea needs more thought about long-term consequences.
CO2 is not a pollutant. Despite the propaganda and ignorant push for it being so, it is naturally occurring, with the anthropogenic portion being such a small addition it’s barely worth mentioning. All humans and animals on earth exhale CO2. The oceans perspire CO2, every volcano kicks out massive amounts of CO2. And the most ironic / moronic concept is CO2 capture. The world is already filled with organic life that recycles CO2 better than anything we can come up with, they’re called trees and plants. They thrive in high CO2 environments. Here’s some simple irrefutable facts. Our climate has never stagnant, it cycles all on its own. Probably more to do with solar cycles than chemicals in the atmosphere. We’ve had numerous ice ages in the past and then periods of warming. The ice ages were not very friendly to life. Life does much better in warm environments. If the planet really is billions of years old then what we’ve observed as far as climate isn’t even a drop of water in the ocean. The sample size isn’t even representative of the population size amd therefore any model we glean from that is useless. Bad model good data, bad predictions . Bad data good model, bad predictions. Right now we have bad model, not enough data so the predictions are worth nothing.
Looks like Mother Earth is sending Florida an abundance of Sargassum to be salted and sequestered.
No watering the crops, and at no cost except harvesting.
Might have to add some salt. I bet a desalinization plant is nearby that has some extra they would like to donate. They might even build a pipeline to the burial pit.
Drone swarms planting trees is the only way out of this.