grounded

[mellowtigger]

Around 25 years ago, a guy at church mentioned something that's stuck in my mind since then. He'd been a plumber for ages, and he'd seen changes in how pipes corrode over the course of his career. He was of the opinion that the earth did not have the same electrical potential that it did in the past. He thought that so much equipment was being "grounded" that the the soil now carried a different charge than it used to.

I vaguely remember my father around this same time period mentioning problems at the Texas Instrument plant where he worked.  They grounded such powerful electrical equipment that they were having problems locating a neutral ground for some new sensitive stuff they were working with.

Technically, "ground" is just a reference point, someplace to measure the difference with another charge. The earth does change its electrical charge naturally, There are various kinds of lightning, but the most common has electrons in the ground rushing to meet positively-charged areas of clouds. (The opposite does occur too.)

We measure soil for its various qualities that promote plant well-being. Things like its clay content, it's chemical pH, its moisture... but what about it's electrical state? What if various microbes prefer a certain electrical state for best health? What if we're changing their environment in yet another way by grounding all of our equipment throughout a city? Google searches find me lots of articles about bacteria that produce electricity to be harvested, but I can't find much on the reverse where the electrical environment is used to heal/harm the bacteria. I found only one that mentioned a pulsed electric field being used to kill bacteria to improve pasteurization.

Comments

[snousle.livejournal.com]

Nothing people do can change the net electric charge of the earth, over more than small areas. Electrical equipment does not create electrons, it just moves existing electrons around. And in any case, total electricity use on Earth is surely a teensy-tiny fraction of the effect caused by the aurora.

[mellowtigger]

Yes, I would expect any effect to be only local. We know that cities change local temperature. I think we change local "ground" as well. I'm curious, though, if that affects microorganisms in the soil. If so, is it helping or harming them? How are they evolving differently than their country-bumpkin peers?

[snousle.livejournal.com]

Organisms can respond to electrical fields, but I don't know of any mechanism that could cause them to respond to a difference in absolute charge. And any field would have to be enormously strong to affect something so small.

I was surprised to read that the electrical field around the Earth is about 100 volts/meter near the surface. Such things are often counterintuitive, but I had no idea the field was that strong. Much less than ordinary static electricity, to be sure, but still larger than I had expected. Interesting article here (http://www.sciam.com/article.cfm?id=detecting-the-earths-elec).