They're also looking at coffee to see whether caffeine declines.
Way to bury the lede, NickS.
I read a book on agricultural policy in Indonesia recently. In the early-mid 20C the government starting rolling out chemical fertilizers to raise rice yields, but initially it didn't work because the plants used the extra nutrients to grow more leaf and stem matter instead of more seeds. It took considerable time to breed varieties that would grow more seed mass instead, but it was done, and the new varieties and fertilizers and pesticides eventually massively increased rice yields (though accompanied by monoculture pest problems). This leads me to think the OP problem will prove soluble. This will indeed take time. In the interim missing micronutrients can quite easily be covered with supplements, like with iodated table salt. Missing plant protein is a much bigger problem.
So we should pour salt on rice fields?
There's a paragraph in there about colony collapse disorder. Interesting and troubling stuff.
The stuff mentioned in 2 also leads me to think the invisibility of the problem alluded to in the OP is exaggerated. Invisibility to nutritionists is unsurprising. Plant-breeding people (whatever you call them) have been dealing with analogous problems for decades if not millennia.
Obviously the solution is a "People of Walmart" version of zooplankton. Of course, then the whales might get diabetes.
Or maybe they just need to increase the supply of micronutrients to plants in proportion to the increased supply of CO2. Which would be to say, yes, we should pour salts on rice fields.
They did it too late. The Empire fell because there wasn't enough protein in their bread.
The Romans salted the fields of Carthage to destroy Carthage by preventing it from growing crops.
Protein deficiency would ensure the delinquency of future generations of Carthaginian youth. Like redlining, but much more hardcore.
Anyway, I think maybe salt isn't a micronutrient in short supply in the ocean.
I don't think they can feel pain.
But to your point, yes the ocean is probably full of calcium and zinc salts too. So I guess no ironically saving the world by sowing salt.
12: actually they didn't... salt was quite expensive and you would have needed thousands of tons to make the fields infertile. Actually soils tended to be salt deficient if anything; hence phrases like "the salt of the earth". If they ploughed up Carthage and salted the ground, it was to make sure the ruins were overgrown more quickly...
I'm not even looking anything up to check that. No.
Anyway, either ajay or the people who taught me religion are wrong about the meaning of 'salt of the earth.'
Maybe they metaphorically sterilized the fields with the blood of their soldiers, whom they paid in salt?
They called the pay of Roman legions a "salary" because the Roman legionnaire's weapons had to be in accord with the Strategical Arms Limitation Treaty.
Spaceborne weapons systems had not yet been invented, hence "SALT of the Earth".
You know your punning has arrived when it makes Moby grunt.
19: ok I grant that most of that was made up, but the idea of dumping enough salt on a field to make it infertile is definitely rubbish. Maybe a symbolic gesture?
Like telling Steph Curry he isn't welcome at the White House after he's already told you he won't come.
Or maybe deliberate misuse of irrigation systems, resulting in salinization? That's a thing that happens.
It seems we don't actually have primary sources on the use of salt in Carthage, although we do have extensive tellings of what was done, including certain rituals and invocations of the divine. The earliest reference to salt this scholarly article found was Cambridge Ancient History, 1930!
It is in Judges 9:45 and other Old Testament-era stuff, so that's probably how the idea bled over.
I appreciation the diligence, but the speculation was more fun.
The stuff mentioned in 2 also leads me to think the invisibility of the problem alluded to in the OP is exaggerated.
I think it is the nature of popular science articles to exaggerate the novelty of the research. But I still found the story fascinating.
To be fair to popular science, unpopular science is required to state how novel it is to get funded/published.
33: Fair enough. It is interesting.
Other things I learned in the Indonesia book: (1) historically, subtropical rice areas like Japan and Taiwan have had higher yields than equatorial areas like Indonesia, because they have longer days in summer, permitting more plant growth, though plant breeding eventually dealt with this too; and (2) swampy, peaty soils in Indonesia proved highly acidic and difficult to cultivate. Relevant because the warming world might permit and require crop growth in very high latitudes which (1) have very long summer days and (2) often have swampy, peaty soils. Suggesting, together with the OP problem, that some very long-term agronomy projects need to be started quite urgently.
The article I read was rather vague about the missing nutrients. Were they proteins, minerals, vitamins? Were they things we could provide by other means? If it is just salt, well people could just add salt the way we add folic acid to flour or vitamin D to milk or iodine to salt. I get the impression that calories are not considered nutrients in this context since the algae part of the story suggested that there was some other limiting factor.
Were they proteins, minerals, vitamins?
All of the above, AFAICT. Literally everything but carbs, because (it seems) that plants are responding by getting bigger (cellulose and other structural carbs) and storing more energy (sugars). It's not entirely clear to me why they wouldn't at least take up more minerals, but it seems that they don't.
If CO2 has risen but other nutrients remained constant, there aren't enough minerals?
I don't think you'd see such consistency in the outcomes, though. That is, at least some plants are growing in mineral-rich soils, but the results ni the article seem to be that every plant acts this way.
40: Yeah, I'm just speculating. It's possible though that today the huge majority of food plants, and thus sample in the study, are grown in soils where artificial additives overwhelm the natural mineral composition of the soil. (Still speculating.)