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Big agriculture mislead the public about the benefits of biofuels

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Re: Big agriculture mislead the public about the benefits of biofuels

#241

Post by amy_petrik »

luqtas wrote: post #213
krainboltgreene wrote: post #178

Earlier quoted context omitted.

I don’t believe there’s any evidence to suggest sugarcane regenerates soil. In fact I can only find evidence to the contrary.

even a simple rotation like corn -> soybeans can aid some bacteria recover, thus a better soil lifespan (high productive areas with proper management (beyond rotation, like some rest and proper fertilization can last ~ 120 years being abused all the year long) probably hundreds of years if erosion wasn't a thing [0] but "regenerating" as the OP types is probably about actively managing land recover while planting som…

the crux of ag soil "energy" is just nitrates and stuff. some plants like beans and lentils recharge nitrogen in the soil (hence the old native american trinity or whatever, corn, beans, and some other plant). fertilizer, that's just nitrates. poop and pee (natural fertilizer).. yup, nitrates.

Basic reason would tell us, unless we're using a nitrogen-fixing plant like beans, unless we're using fertilizer, the plant's gonna suck up nitrates from the soil, get harvested, and now there's less nitrates in the soil. Weakening the soil quality thusly. Pretty straightforward.

Biologically you could then go on to argue micronutrients along the same lines, with poop and pee more likely to contain those things, since aminals also are eurkaryotes so probably depend on some of the same

Re: Big agriculture mislead the public about the benefits of biofuels

#242

Post by AngryData »

Cthulhu_ wrote: post #118
raverbashing wrote: post #104

Earlier quoted context omitted.

That being said, growing corn for fuel ethanol is stupid. Other crops are more efficient (Unless we find a way of turning the whole plant into fuel)

What crops are those, and do they grow in the same climates and soils as corn does at the moment?

Sugarbeets would probably be the best for easy usage in non-tropical areas. I would think most sweet crops would beat corn though, corn by itself isn't that efficient because of how much energy goes into growing the stalk. But it is one of the most robust with a huge range of soils and climates which lends to its prevalence

Re: Big agriculture mislead the public about the benefits of biofuels

#243

Post by Gibbon1 »

quickthrowman wrote: post #228
Gibbon1 wrote: post #68

Earlier quoted context omitted.

Unless I'm going senile, I've done this calculation a few times and consistently I get that a solar farm produces 25-50 times more energy a year than corn.

You can eat corn if food imports aren’t available, but as far as I’m aware, photovoltaic cells are not edible. Food security is the primary reason for corn overproduction and ethanol is what we do with the excess corn instead of let it rot.

I've read a few references to electrocatalysts where you use electricity to promote reactions potentially ones that are endothermic.

One wonders a bit, you take hydrogen and nitrogen to make ammonia. Then you spray that on a field and grow plants to turn it into protein. What if you skip the plant step and convert the ammonia to amino acids directly.

Re: Big agriculture mislead the public about the benefits of biofuels

#244

Post by karolinepauls »

lazide wrote: post #163
karolinepauls wrote: post #154

Earlier quoted context omitted.

The world is more complicated than a 17th century lab experiment in combustion. Forests sequester carbon through forest fires producing charcoal. Humans could actually cut down old trees, dry them, and convert them to charcoal later used for soil enrichment. Wetlands capture carbon by incorporating wood from dead trees in anoxic conditions. > When plant productivity exceeds decomposition, net soil carbon accumulation…

Bwahaha, this is so ridiculous. Show me the megatons/year of charcoal being produced by the worlds forests eh? We could process them yes, but we can also just make them into timber - or burn them for energy. Or just bury them somewhere under a bunch of clay. Oh, and now we’re back to this thread.

It's as ridiculous as the comparison of the most recent 12k years of the holocene to the age of plant life on the Earth.

As for using lumber for timber, when eventually disposed it would have to be turned into charcoal rather than burned for energy or let decompose in conditions that don't sequester carbon.

You also missed the point about using charcoal for soil enrichment.

Re: Big agriculture mislead the public about the benefits of biofuels

#245

Post by lazide »

karolinepauls wrote: post #244
lazide wrote: post #163

Earlier quoted context omitted.

Bwahaha, this is so ridiculous. Show me the megatons/year of charcoal being produced by the worlds forests eh? We could process them yes, but we can also just make them into timber - or burn them for energy. Or just bury them somewhere under a bunch of clay. Oh, and now we’re back to this thread.

It's as ridiculous as the comparison of the most recent 12k years of the holocene to the age of plant life on the Earth. As for using lumber for timber, when eventually disposed it would have to be turned into charcoal rather than burned for energy or let decompose in conditions that don't sequester carbon. You also missed the point about using charcoal for soil enrichment.

There is zero chance this makes a difference at the scales required. That is my point. Or are you proposing somehow making billions of tons of lumber into charcoal a year, and stopping it from further decay?

There isn’t enough room. Let alone equipment.

and it sure isn’t what happens naturally.

Re: Big agriculture mislead the public about the benefits of biofuels

#246

Post by lazide »

littlexsparkee wrote: post #207
lazide wrote: post #55

Earlier quoted context omitted.

Forests are not long term carbon sinks. They flatline rather quickly. This is obvious to anyone who has spent much time in a forest, because if this wasn’t the case, forests would be sitting on thousands of feet of sequestered carbon. Instead of a few feet (typically) of non-mineral soil. Forests also (typically) go through cycles of burning. The highest rate of carbon sequestration is when a forest is in the 3-25 ye…

Even fast growing trees need 10-20 years to start storing significant amounts of carbon and old-growth forests can sequester it for hundreds of years.

The challenge is that old growth forests, while retaining carbon, don’t pull much net carbon from the atmosphere. Their ‘spring’ is nearly fully compressed.

They are really beautiful and important, but they aren’t doing much when it comes to reducing atmospheric carbon anymore.

As ugly as it is, chopping them down (as long as we can stop the wood from rotting/burning/etc) and then having new trees grow in their place does more actual atmospheric carbon reduction.

Re: Big agriculture mislead the public about the benefits of biofuels

#247

Post by analog31 »

amy_petrik wrote: post #241
luqtas wrote: post #213

Earlier quoted context omitted.

even a simple rotation like corn -> soybeans can aid some bacteria recover, thus a better soil lifespan (high productive areas with proper management (beyond rotation, like some rest and proper fertilization can last ~ 120 years being abused all the year long) probably hundreds of years if erosion wasn't a thing [0] but "regenerating" as the OP types is probably about actively managing land recover while planting som…

the crux of ag soil "energy" is just nitrates and stuff. some plants like beans and lentils recharge nitrogen in the soil (hence the old native american trinity or whatever, corn, beans, and some other plant). fertilizer, that's just nitrates. poop and pee (natural fertilizer).. yup, nitrates. Basic reason would tell us, unless we're using a nitrogen-fixing plant like beans, unless we're using fertilizer, the plant's…

Indeed, but high intensity agriculture at a scale to feed earth's population consumes more nitrogen than can be obtained through crop rotation.

Re: Big agriculture mislead the public about the benefits of biofuels

#248

Post by 9rx »

jandrese wrote: post #238
9rx wrote: post #166

Earlier quoted context omitted.

The trouble with corn is that its yield band is huge. Get a good growing year and suddenly you have twice as much as you need — and more than you can store, leaving it out to rot. Recapturing that energy as fuel instead of disappearing waste heat is a win and what corn-based ethanol was introduced for. The trouble with humans is that they aren't very good at moderation. As soon as they see a little opportunity to do…

The other problem is that the equipment to turn corn into ethanol isn't free, either to buy or to maintain. It's not economical to leave it idle during poor yield years.

> It's not economical to leave it idle during poor yield years.

Poor yield implies high prices. It is not economical for anything but to leave it idle. And, as you'd expect, when corn was expensive a few years ago many ethanol plants did shut down.

For a short while around 2010, following a massive glut of corn through the early 2000s, the US government was paying ethanol producers to produce when corn was otherwise too expensive to work economically in an effort to jumpstart the industry. But those days are long behind us.

Re: Big agriculture mislead the public about the benefits of biofuels

#249

Post by quickthrowman »

Tadpole9181 wrote: post #236
quickthrowman wrote: post #230

Earlier quoted context omitted.

Just one question: can you eat photovoltaic cells? Corn is edible, and I’d be more than happy to eat cornmeal for years in the event of a global war that stopped food imports/exports. This is precisely the reason for agricultural subsidies, to ensure our nation can feed itself if all agricultural trade is cut off. We’d grind up field corn and eat cornmeal instead of starving to death with plenty of electricity but no…

Ethanol corn is not the food corn, to be clear. It is bred to have as little sugar and as much starch as possible. It's inedible, unless you're a pig that likes corn byproduct or drinking corn oil. And, in the event of global war, I think we could end our enormous agriculture exports and be more concerned with a nuclear war than if we can eat corn for every meal. If this was about that, we would grow something else.…

You can grind field corn into cornmeal, that’s what they use for tortilla chips, tortillas, etc

Lobbying can have much higher returns than the 4-6% yield from renting farmland to operators, it’s about food security, not handouts.

Re: Big agriculture mislead the public about the benefits of biofuels

#250

Post by anticensor »

Geee wrote: post #168
pfdietz wrote: post #156

Earlier quoted context omitted.

Soil too eventually reaches an equilibrium where carbon injection and carbon oxidation are in balance. If what you thought was true, imagine a forest sitting there for millions of years. Where would this permanently sequestered carbon be going? Soils do not become unboundedly thick.

Well, that's what oil and coal are. Oil is formed from marine biomass, and coal is formed from plants.

Coal no longer forms, oil is still forming but far slower than the rate consumed.
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