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.
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.
But that will reduce profit
Shhh, you’ll scare the shareholders.
Potassium is produced by breaking down potassium-rich rocks. Plants cannot replenish it like they replenish nitrogen.
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.
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
The deeper problem is that it makes ‘financial sense’ to let a lot of people starve.
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…
This is possible, but plants with deep roots (shrubs, certain grasses and scrubs) usually take longer to grow.
Potasium is a mineral. When it is gone it is gone. Nitrogen is replenishable, but minerals need to be brought back some other way.
… where exactly do you think the potassium goes?
Also Potassium is a chemical element not a mineral, though it occurs in many minerals.
… Into the plants? Or washed away/blown away with soil? Seems pretty straightforward.
And do you suppose the potassium is “stuck” or locked away into those plants forever?
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.
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.
… Did you miss where I wrote
Maybe read the actual article.
You did read the article, or at least the summary, right? It’s discussing shortage of fertiliser due to supply issues
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.
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.
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.
Farmers do buy fertilizer. The concern is how that fertilizer is produced.
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?
How would crop rotation replenish a physical element that can’t be pulled out of the air, though?