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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

#171

Post by hinkley »

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…

Methane is 20x worse, so if you capture 95% of the carbon and emit the rest as methane, you've broken even on GHG. But nothing I'm aware of captures 95% of carbon. Terra Preta might lock up the captured carbon for 100's of years, but producing charcoal is 50% efficient if you optimize for emissions, which most people do not.

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

#172

Post by unaindz »

lettergram wrote: post #117
matthewdgreen wrote: post #55

Earlier quoted context omitted.

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.

I want a warmer atmosphere. All the UN data points to a warmer atmosphere equating to more food and higher quality of life. I concede some concern about potential feedback loops, but the reality is that earth was and still is in an ice age. Ice ages are not the norm on earth, I think it’s okay if we exit an ice age. Yes things will change, but it’ll be over decades to millennia. We’re working on carbon capture right…

I live in northern Spain and I notice the summers and the winters getting hotter.

This winter I didn't turn on the heat once and it was uncomfortable cold inside the house for like three days tops. It's normally uncomfortable at least for one or two months.

On december it's freezing outside at night, this december we had flowers blossoming. What an issue right? Energy and money savings on all that gas and it's more comfortable outside.

Well we beat the last hot temperature record last summer with 45⁰C, that's "kills your grandpa temperature" or 113F if you prefer. I'm scared of this summer, I don't have AC.

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

#173

Post by hinkley »

s1artibartfast wrote: post #128
crazygringo wrote: post #59

Earlier quoted context omitted.

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…

I think they are right. Yes, the more rice there is, the higher the steady state would be. However, we aren't planting more rice. The ammount of rice grown and methane released is already in steady state. This is a seperate point than if atmospheric methane would go down if we grew less rice than today.

If you grow more people, we will have more rice. If perennial rice is more profitable, then corn acreage will shrink in favor of rice acreage.

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

#174

Post by hinkley »

photochemsyn wrote: post #155
CrazyStat wrote: post #136

Earlier quoted context omitted.

> and while there is some anaerobic production of methane in rice paddies, the methane gets converted back to CO2 in the atmosphere with a half-life of 10-20 years IIRC. Methane is a far, far worse greenhouse gas than CO2, even accounting for the fact that it eventually decays back to CO2.

Methane is something like 25 times as effective at absorbing outgoing infrared radiation in the Earth's atmosphere relative to carbon dioxide, but there is > 200 times as much CO2 in the atmosphere as methane (1.9 ppm vs 420 ppm). https://www.noaa.gov/news-release/increase-in-atmospheric-me... So the net effect of all the methane is about 50 ppm. About 30% comes from fossil fuels. This leaves a big burp relative to p…

And melting permafrost.

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

#175

Post by thaumasiotes »

sampo wrote: post #168

In one of his videos in Youtube, permaculture farmer Richard Perkins said that mankind has 6000 years of agriculture, but has mostly concentrated plant breeding efforts to annual plants. We mostly eat annuals. (Plants that grow and die in one year.) But, he said, imagine what kind of perennial (plants that live multiple years) food plants we could have, if we invested similar 6000 years of effort to perfecting perenn…

> But, he said, imagine what kind of perennial (plants that live multiple years) food plants we could have, if we invested similar 6000 years of effort to perfecting perennial food plants. Like fruit trees and nut trees and whatever.

Well, that's something we've already done. So I'd say we'd end up with the fruits and nuts that we have right now. What are we supposed to be imagining?

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

#176

Post by hinkley »

maxerickson wrote: post #99
twawaaay wrote: post #37

Earlier quoted context omitted.

I am not convinced (I grew up on a farm). It is usually harder to get rid of any weeds when your crop is growing on the field. After harvest, you just get rid of everything, turn the soil (but I don't know anything about rice farming) and you kinda get a fresh start. ON THE OTHER HAND, we already have robots that can easily identify weeds with a camera and zap them with lasers or other shit. Which just seems so much…

It seems they are not gently collecting the individual grains of rice. http://en.people.cn/n3/2021/1025/c90000-9911067.html

You should see how they harvest lavender. If I were an anthropomorphic plant I'd probably loose my lunch after seeing one of those videos.

This is my impression of why we can get away with this. Annuals tend to gamble with weather conditions. There's enough seed bank stored up from previous years that if a scouring windstorm breaks all of the stalks in an area, then the seed bank can help recover next year, and if that's not enough then some seeds will blow in from the edges eventually, and ten years from now you can't tell.

Perennial plants have to be sturdier. Only some, such as alpine species, are adapted to drop damaged limbs. They are used to being jostled by hail, storms, and herd animals, so the insult is less permanent.

I don't know how that translates to perennial grasses, except that most such grasses can and sometimes do burn to the ground, and regrow each year from rhizomes. Half the plant survives each growing season, and the other half is sacrificial.

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

#177

Post by lkbm »

sampo wrote: post #168

In one of his videos in Youtube, permaculture farmer Richard Perkins said that mankind has 6000 years of agriculture, but has mostly concentrated plant breeding efforts to annual plants. We mostly eat annuals. (Plants that grow and die in one year.) But, he said, imagine what kind of perennial (plants that live multiple years) food plants we could have, if we invested similar 6000 years of effort to perfecting perenn…

I was recently thinking about the possibility of GMOing/selectively breeding better hardwood. (Turns out we have done this with walnut.)

I believe the main issue is that the lifecycle of tree is much longer. Each year I can select the best corn from last harvest and plant it for this harvest. Trees generally take several years to start producing, so iterating through generations is slow.

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

#178

Post by hinkley »

JamisonM wrote: post #78
twawaaay wrote: post #37

Earlier quoted context omitted.

I am not convinced (I grew up on a farm). It is usually harder to get rid of any weeds when your crop is growing on the field. After harvest, you just get rid of everything, turn the soil (but I don't know anything about rice farming) and you kinda get a fresh start. ON THE OTHER HAND, we already have robots that can easily identify weeds with a camera and zap them with lasers or other shit. Which just seems so much…

I am a farmer. It is quite close to impossible for weeds to establish once many crops reach a certain stage, this is pretty consistent with the perennial idea. Stripper headers are quote commonly used all over the world: https://youtu.be/nppu5OfjisQ?t=90 The assertion that a perennial plant "cannot be damaged" is also incorrect, many perennial crops benefit agronomically from a "trim", even non-perennials have econom…

Permaculturist here.

With the exception of trees, most plants that establish after their taller peers do not try to dominate the canopy. They have already lost that fight. Instead they either stay low and work with the limited light available, or they aggressively grow in the spring to complete their entire lifecycle before the deciduous canopy closes at the beginning of summer. They might steal a little fertilizer, and some water, but the jury is still out on whether some plants conserve as much water as they use. It's a fuzzy enough area that you can find people who claim that some plants increase total available water.

We are just beginning to fully appreciate all of the ways trees have to ladder up from the forest floor to the canopy, and some of the things we perceive as competition may be a misunderstanding.

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

#179

Post by xsmasher »

awesomeMilou wrote: post #15
quaintdev wrote: post #10

Earlier quoted context omitted.

I have one concern though. What happens to nutrients content of this rice over time? I mean with our current practices the land gets enough time to produce quality rice for another year. If we are going perenial what happens to soil and rice quality?

Do riceplants absorb nutrients only via soil? I've always thought that they get at least part of their nutrients via the water that surrounds them. In that case controlling for nutrients would be much easier.

Rice is not an aquatic plant; the water is used for weed control. California grows rice but they don't flood the fields.

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

#180

Post by hinkley »

contingencies wrote: post #77
twawaaay wrote: post #37

Earlier quoted context omitted.

I am not convinced (I grew up on a farm). It is usually harder to get rid of any weeds when your crop is growing on the field. After harvest, you just get rid of everything, turn the soil (but I don't know anything about rice farming) and you kinda get a fresh start. ON THE OTHER HAND, we already have robots that can easily identify weeds with a camera and zap them with lasers or other shit. Which just seems so much…

With typical rice farming in Asia, you see manual transplanting of each seedling in to small fields by women and children. This is back-breaking work and extremely slow. I can't think of another crop both this widely cultivated and painstaking. Therefore, not having to do this is a huge win. China has a multitude of climatic areas. Some harvest rice once per year, others two or three times per year. Even within Yunna…

It might be dated information, but I'd heard 3 crops per year going back at least as far as 1900 (Farmers of Forty Centuries), but not that it was three rice crops per year. Instead a rotation of different crops in the same field.

One of the tricks with rice is you can germinate it in one field, then transplant it to something like 4-6 times the same space to grow to maturity.

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