I was talking to a guy who told me that a company was working on a process to “infuse” water with oxygen. He said that it would be used in places where fish weren’t able to survive because the oxygen in the water was being depleted. He went on to say that it could also be used for irrigation, since it’s good for plants.
Whoa! Fish tanks have bubblers and I’ve heard of fisheries being wiped out because of algae (or something) depleting the oxygen. But plants? I can’t help but think that that may be a bunch of bull. Would more oxygen in irrigation water be good for plants?
Nope, that’s only when they’re photosynthesizing, and also only in the above-ground parts. The roots always need oxygen, and so does the rest of the plant when it’s dark; they switch to normal cellular respiration when there’s no light.
As to “a company was working on a process to “infuse” water with oxygen”… I hope the guy was understating the level of research they’ve been doing - because we’ve already being oxygenating water for decades and probably longer already; it’s very simple.
Over a hundred years ago the first thing considered in any kind of cold-water fish hatchery was how to ensure there was enough oxygen in the water; not a new idea. Adding oxygen to anaerobic (or nearly so) water for fish out in the environement is usually a waste of time as it’s only a bandage to the problem. Something is depleting the O2; that’s what usually has to be addressed - because as soon as the system fails (and they ALL do at some point), the fish will all die in short order.
I don’t know how well super-saturating irrigation water would work; again it sounds like a wasted effort. Most irrigation systems are open to air, so all the extra O2 would just diffuse into the atmosphere anyways. If the plants are grown in properly prepared soil, it’s porous enough to allow all the atmospheric O2 the roots need to diffuse into the soil. Plus you seldom irrigate crops - it’s not a daily thing - so you’d only be giving them extra O2 for a few hours out of a growing season.
In hydroponic systems air bubblers are used to make sure there is enough O2 in the water around the roots, but this is not an irrigation application. I think the guy has left out most of the details of what his company is doing. Maybe he means they are trying to chemically bind O2 to the water molecules so it doesn’t diffuse away… then again how living organisms would be able to use it I don’t know…
Your skepticism is well placed. Diffusion of Oxygen into or out of agitated water is fast. While an open, unstirred ~3cm X 0.8cm wide container of deoxygenated water will stay deoxygenated for 20 minutes or so, gentle stirring will get it fully oxygenated in under a minute. Tiny droplets zipping through through the air likely reach equilibrium before they hit the ground. While injecting oxygen directly into the soil might benefit growth, especially with wet, anoxic soils, it will also affect the growth of soil organisms. That may, or may not, be a good thing as far as the plant is concerned.