this post was submitted on 22 Apr 2024
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Potassium deficiency in agricultural soils is a largely unrecognised but potentially significant threat to global food security if left unaddressed, finds new research involving researchers at UCL, University of Edinburgh and the UK Centre for Ecology & Hydrology.

The study, published in Nature Food, found that more potassium is being removed from agricultural soils than is being added, throughout many regions of the world. It also gives a series of recommendations for how to mitigate the issue.

Potassium is a vital nutrient for plant growth that helps with photosynthesis and respiration, the lack of which can inhibit plant growth and reduce crop yields. Farmers often spread potassium-rich fertilisers over their fields to replenish the depleted nutrient, but supply issues can inhibit its use, and there are lingering questions about its environmental impact. 

The researchers report that globally, about 20% of agricultural soils face severe potassium deficiency, with particular regions likely to experience more critical shortages, including 44% of agricultural soils in South-East Asia, 39% in Latin America, 30% in Sub-Saharan Africa and 20% in East Asia, largely due to more intensive agricultural practices.

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[–] reddig33 33 points 8 months ago* (last edited 8 months ago) (5 children)

~~Pretty sure there are crops you can rotate in that replenish the soil.~~ Edited because crop rotation doesn’t produce Potassium as pointed out by replies — it’s a mineral. Organic waste does include potassium though.

There’s also a literal shitload of organic waste that humans generate that can be used for a similar purpose instead of burying it in landfills.

[–] [email protected] 13 points 8 months ago (1 children)

But that will reduce profit

[–] Soup 12 points 8 months ago

Shhh, you’ll scare the shareholders.

[–] [email protected] 12 points 8 months ago (2 children)

Pretty sure there are crops you can rotate in that replenish the soil.

Potassium is produced by breaking down potassium-rich rocks. Plants cannot replenish it like they replenish nitrogen.

There’s also a literal shitload of organic waste that humans generate that can be used for a similar purpose instead of burying it in landfills.

We do produce a lot of potassium-rich waste - sewage and food waste, for example - but most of it is also rich in other nutrients. So you can add a little of it, but adding too much of it can cause other problems (like eutrophication).

The other solution is to buy potassium fertiliser. A significant amount of this is produced in Russia, Kazakhstan and Ukraine, and I'm guessing its trade is being affected by the ongoing war.

[–] reddig33 6 points 8 months ago* (last edited 8 months ago) (1 children)

Potash has been a huge chunk of the potassium supply, with most of it coming from Canada. But reports indicate we can’t keep up with the demand and it’s driving up prices.

https://link.springer.com/chapter/10.1007/978-94-007-0394-0_11

If it’s really a dire problem, it will make financial sense to start separating the potassium from organic waste and to divert food manufacturing byproducts like banana peels from animal feeds to fertilizer production.

Brine from desalination also contains potassium (among other important things). We’re going to have to start desalinating soon anyway.

https://www.nature.com/articles/s41545-022-00153-6

[–] [email protected] 3 points 8 months ago

The deeper problem is that it makes 'financial sense' to let a lot of people starve.

[–] Hule 3 points 8 months ago (1 children)

I've read that plants with deeper roots can "bring up" nutrients from lower layers, which would help in the shorter term.

Longer term? No time to think about that..

[–] [email protected] 2 points 8 months ago

This is possible, but plants with deep roots (shrubs, certain grasses and scrubs) usually take longer to grow.

[–] [email protected] 8 points 8 months ago (1 children)

Potasium is a mineral. When it is gone it is gone. Nitrogen is replenishable, but minerals need to be brought back some other way.

[–] Cypher 5 points 8 months ago* (last edited 8 months ago) (2 children)

… where exactly do you think the potassium goes?

Also Potassium is a chemical element not a mineral, though it occurs in many minerals.

[–] [email protected] 4 points 8 months ago (1 children)

... Into the plants? Or washed away/blown away with soil? Seems pretty straightforward.

[–] Cypher -2 points 8 months ago (1 children)

And do you suppose the potassium is “stuck” or locked away into those plants forever?

[–] [email protected] 9 points 8 months ago* (last edited 8 months ago) (1 children)

No. It goes into the people/animals eating those plants, and from there to a million different places that aren't farm fields.

That's the problem: that potassium doesn't cycle back to the soil it came from. Farmers have to rely on adding mined potash to the soils to compensate for that loss. The entire point of the article is potassium is being removed from the soil faster than it's being added back in.

[–] Cypher -1 points 8 months ago (2 children)

We put nitrogen in fertiliser and for some reason you think it’s impossible to put potassium in? Really?

Potassium is a key component of any fertiliser.

[–] [email protected] 2 points 8 months ago

We put nitrogen in fertiliser and for some reason you think it’s impossible to put potassium in? Really?

... Did you miss where I wrote

Farmers have to rely on adding mined potash to the soils to compensate for that loss.

Maybe read the actual article.

[–] [email protected] 1 points 8 months ago (1 children)

You did read the article, or at least the summary, right? It's discussing shortage of fertiliser due to supply issues

[–] Cypher 0 points 8 months ago (1 children)

I was addressing the ridiculous claim that potassium cannot be replaced.

Now if you’re not going to actually read and comprehend a comment chain you can piss off.

[–] [email protected] 0 points 8 months ago (1 children)

Farmers have to rely on adding mined potash to the soils to compensate for that loss.

You mean this sentence in the comment you replied to? This sentence that claims potassium cannot be replaced?

[–] Cypher 0 points 8 months ago* (last edited 8 months ago)

https://kbin.social/m/[email protected]/t/978925/-/comment/6321012

Reading comment chains and keeping track of them isn’t hard. If you continue to experience cognitive issues please seek medical assistance.

Edit: in case you have issues accessing the link

Potasium is a mineral. When it is gone it is gone. Nitrogen is replenishable, but minerals need to be brought back some other way.

[–] [email protected] 4 points 8 months ago (1 children)

Err, yeah. Not a mineral but an element. my mistake

it leaves the field with the food we take off. from there it ends up in landfills and sewer systems. None go back toethe field.

[–] Cypher 2 points 8 months ago (1 children)

You reckon farmers are too stupid to buy fertiliser with sufficient potassium in it?

You literally get potassium back in the cycle just from composting waste.

[–] [email protected] 1 points 8 months ago

Farmers do buy fertilizer. The concern is how that fertilizer is produced.

[–] Francisco 5 points 8 months ago

What do you even mean with your word salad?

Your first sentence/paragraph is absurd in the post's context. Crop rotation will not replenish the soils' potassium.

And in your 2nd paragraph.. what do you mean by "similar purpose"? It's ambiguous, how you have used it. Also, do you know anything of how fertilizers work?

Quick quiz: Wheat has b12 vitamin and iodine, can you just eat more bread to replenish your body's neads for those nutrients? Or does a balanced diet need to be ..balanced for all nutrients?

[–] [email protected] 5 points 8 months ago

How would crop rotation replenish a physical element that can't be pulled out of the air, though?

[–] I_Fart_Glitter 27 points 8 months ago (1 children)
[–] [email protected] 19 points 8 months ago (1 children)

Have you tried just giving them water?

—Like... from the toilet??

[–] [email protected] 12 points 8 months ago (1 children)

"Well, I mean, it doesn't have to be out of the toilet, but, yeah, that's the idea."

idiocracy is such a great movie! Mike Judge definitely has a unique style

[–] [email protected] 4 points 8 months ago

Mike Judge is a prophet.

[–] Raiderkev 9 points 8 months ago

Quick, someone call Kazakhstan!