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Perennial rice: Plant once, harvest again and again

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Re: Perennial rice: Plant once, harvest again and again

#51

Post by replygirl »

eulgro wrote: post #44
knodi123 wrote: post #35

Earlier quoted context omitted.

I litter frequently. Some people criticize me for it, but I rightly point out that my own litter is a tiny fraction of city-wide litter, and if I stopped, no one would even notice the difference. I'm not even the biggest contributor! Mechanized recycling trucks hoist the bins high in the air and let stuff fall into a hopper on the back, and on a windy day, every single bin they pick up produces a few pieces of litter…

I kill people frequently. Some people criticize me for it, but I rightly point out that my own murders is a tiny fraction of city-wide deaths, and if I stopped, no one would even notice the difference. I'm not even the biggest contributor! Fast-food restaurants and soft drink companies keep promoting unhealthy diets from which people develop diseases which eventually leads to thousands deaths per year. Plus, most peo…

littering is not on the same moral plane as murder though

Re: Perennial rice: Plant once, harvest again and again

#52

Post by TheRealPomax »

melling wrote: post #36
TheRealPomax wrote: post #26

Earlier quoted context omitted.

Why do people keep pretending that we can only focus on one industry at a time? News flash: WE CAN ADDRESS MORE THAN ONE AT A TIME. What about coal? You tell me, what part of fixing rice production interferes with shutting down coal mining? Because as far as anyone can tell, the answer is not a single part.

We already are seeing climate issues. We could have been off coal by now. “A 100 years of coal emissions is 1000 years of rice” By not addressing the big problems sooner, we have shortened the window to seeing significant problems. We’d have more time to solve the smaller problems, or they may take of themselves. For example, the population in China will drop significantly in this century. Unfortunately, it sounds li…

You are aware that there are eight billion humans on the planet, right? If everyone helped, we'd already be done: they're not. But conversely, it's not like we have ten people and we can either put them on coal, or on rice. We have millions of people actively involved at all levels, and the folks tackling rice have zero qualifications to solve coal, and vice versa.

It's like complaining that the folks making bicycles aren't making office buildings: stop being part of the problem by pretending these are mutually exclusive problems to solve and that people should stop trying to solve entire percentage values. 2% is not "a drop in the bucket", 2% is a huge number.

We can have different people work on different problems at the same time. By insisting we don't do something in parallel, all you're doing is telling folks to stop solving problems they can solve at an industrial scale. Are you solving coal, right now? No? Why are you wasting time and not solving coal? Oh you're doing something else atm? Why aren't you dropping that on the spot and solving coal? This is not a constructive attitude, it's flat out being part of the problem.

Re: Perennial rice: Plant once, harvest again and again

#53

Post by xyzzyz »

squokko wrote: post #48
xyzzyz wrote: post #45

Earlier quoted context omitted.

> So, perennial rice may end up reduce GHG emissions substantially. Not really. These GHG emissions from rice are in steady state with the amount of CO2 and methane in the atmosphere. They do not add additional GHG to the atmosphere the way burning fossil fuel do. When you burn fossil fuels, the carbon atoms released into atmosphere have been captured from the atmosphere millions years ago. When weeds and other organ…

Not true between CO2 and methane. The total amount of carbon is the same but in methane form is worse for greenhouse effect.

Methane is worse, but it again doesn’t matter here, because the fields are in steady state not only with CO2, but with methane as well.

Methane doesn’t linger in atmosphere forever, it decomposes into CO2 in a decade or so. This means atoms of methane emitted from the fields are pretty much exactly paired with atoms of methane in atmosphere decaying into CO2.

This means that methane emitted from the fields doesn’t increase the total amount of methane in the atmosphere, the way burning fossil fuels does with CO2.

Re: Perennial rice: Plant once, harvest again and again

#54

Post by crazygringo »

xyzzyz wrote: post #45
chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

> So, perennial rice may end up reduce GHG emissions substantially. Not really. These GHG emissions from rice are in steady state with the amount of CO2 and methane in the atmosphere. They do not add additional GHG to the atmosphere the way burning fossil fuel do. When you burn fossil fuels, the carbon atoms released into atmosphere have been captured from the atmosphere millions years ago. When weeds and other organ…

Can you elaborate on this?

Do you mean that rice plants are actually absorbing methane earlier on, so they're just releasing the same amount?

Or are they actually producing methane from other molecules, like water and carbon dioxide?

Because yes, methane breaks down in the atmosphere into H2O and CO2 so you could view it as a cycle, but the more rice there is the higher the steady state methane in the atmosphere is, so it's still a problem.

Re: Perennial rice: Plant once, harvest again and again

#55

Post by matthewdgreen »

xyzzyz wrote: post #45
chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

> So, perennial rice may end up reduce GHG emissions substantially. Not really. These GHG emissions from rice are in steady state with the amount of CO2 and methane in the atmosphere. They do not add additional GHG to the atmosphere the way burning fossil fuel do. When you burn fossil fuels, the carbon atoms released into atmosphere have been captured from the atmosphere millions years ago. When weeds and other organ…

Methane and CO2 are very different things. The former has a massively greater warming effect than the latter, and takes long enough to degrade in the atmosphere that it can significantly affect warming times. If you aren’t paying attention to the rising methane levels in our atmosphere (and possible evidence of a feedback loop) with serious trepidation, you’re a lucky person who probably sleeps well at night.

Re: Perennial rice: Plant once, harvest again and again

#56

Post by littlestymaar »

xyzzyz wrote: post #53
squokko wrote: post #48

Earlier quoted context omitted.

Not true between CO2 and methane. The total amount of carbon is the same but in methane form is worse for greenhouse effect.

Methane is worse, but it again doesn’t matter here, because the fields are in steady state not only with CO2, but with methane as well. Methane doesn’t linger in atmosphere forever, it decomposes into CO2 in a decade or so. This means atoms of methane emitted from the fields are pretty much exactly paired with atoms of methane in atmosphere decaying into CO2. This means that methane emitted from the fields doesn’t in…

This reasoning is completely wrong: there's an input and an progressive decay as output, the amount of methane in the atmosphere at any given point is directly related to the input.

Re: Perennial rice: Plant once, harvest again and again

#57

Post by onemiketwelve »

there's this perennial green onion mutant that I found out about from people growing it in China. Usually if you want scallions you have to harvest them very quickly, then the plant is kinda useless. But these ones, instead of flowering, they immediately offshoot new plants from where the flower would have been. https://en.wikipedia.org/wiki/Tree_onion

Re: Perennial rice: Plant once, harvest again and again

#58

Post by dangjc »

xyzzyz wrote: post #45
chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

> So, perennial rice may end up reduce GHG emissions substantially. Not really. These GHG emissions from rice are in steady state with the amount of CO2 and methane in the atmosphere. They do not add additional GHG to the atmosphere the way burning fossil fuel do. When you burn fossil fuels, the carbon atoms released into atmosphere have been captured from the atmosphere millions years ago. When weeds and other organ…

That’s reassuring we are in steady state. If perennial rice takes over, we will gradually drop atmospheric methane to a lower steady state.

Re: Perennial rice: Plant once, harvest again and again

#59

Post by crazygringo »

xyzzyz wrote: post #53
squokko wrote: post #48

Earlier quoted context omitted.

Not true between CO2 and methane. The total amount of carbon is the same but in methane form is worse for greenhouse effect.

Methane is worse, but it again doesn’t matter here, because the fields are in steady state not only with CO2, but with methane as well. Methane doesn’t linger in atmosphere forever, it decomposes into CO2 in a decade or so. This means atoms of methane emitted from the fields are pretty much exactly paired with atoms of methane in atmosphere decaying into CO2. This means that methane emitted from the fields doesn’t in…

That doesn't make sense mathematically.

Because you could start with zero methane in the atmosphere, just lots of CO2, but the rice would introduce methane.

Eventually yes you can get to a steady state of methane, but the point is that the more rice there is, the higher that steady state becomes. Which is bad.

So the total amount of methane would absolutely increase. (And if you stopped planting rice at all it would eventually decrease over the subsequent decades.)

Re: Perennial rice: Plant once, harvest again and again

#60

Post by eYrKEC2 »

twawaaay wrote: post #33

I know Chinese harvest their rice up to three times a year. I don't see how perennial rice could compete. Harvesting normal rice is just grabbing entire plants, as many as you can grab at a time. I may know nothing about how harvesting perennial rice is supposed to work, but I grew up as a farmer and I have imagination. You have to leave some part of the plant for it to keep growing crop which means you can't just gr…

Grain combines chop the heads off the wheat plant and leave stubble. If it can survive that.
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