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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

#261

Post by Retric »

Timon3 wrote: post #249
Retric wrote: post #234

Earlier quoted context omitted.

It’s climate change . If global methane from rice fields is identical in 2000, 2023, and 2050 … it has zero impact on climate change. Rice cultivation isn’t completely static, so the it’s changes in rice cultivation that result in climate change.

Rice cultivation hasn't been a factor in climate for all time, only relatively recently. The increase in methane can have an accumulating warming effect. Think about it like this - the amount of rice fields is the derivative of climate change. If you increase the amount of rice fields once and don't decrease it, climate change will slowly but surely rise, even if rice fields don't increase.

10,000 years isn’t relatively recently on the scales of human civilization nor how quickly the climate feedback loops operate.

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

#262

Post by Timon3 »

Retric wrote: post #260
Timon3 wrote: post #258

Earlier quoted context omitted.

> All energy it receives from the Sun is radiated away promptly. The greenhouse effect works by delaying this radiation. The more the radiation is delayed by, the more energy is buffered in steady state. Make no mistake though: all of the energy from the Sun is radiated away rather quickly. This is easily disproven. The Earth does trap heat - we can measure this, it's called the Earth Energy Imbalance. This imbalance…

That’s true, but we’ve been cultivating rice for thousands of years. When people talk about returning the earth to pre industrial levels that’s a world with significant rice cultivation going back long enough to account for such differences. The global energy imbalance is simply lag before temperature’s equilibrium, when you turn up the heat in your house it takes longer to heat your fireplace than a wood door. That…

> That’s true, but we’ve been cultivating rice for thousands of years.

How much rice did we previously cultivate, and how many of those fields were flooded? Around 1900 the world population was around 2 billion, so I feel confident in assuming that we've since strongly increased the amount of farms. As such I don't see how this matters. Cultivation is not a boolean state.

> The global energy imbalance is simply lag before temperature’s equilibrium, when you turn up the heat in your house it takes longer to heat your fireplace than a wood door. That same effect takes longer on the scale of the earth but it’s an exponential decay.

Yes, this is what I've been saying. Increasing the amount of methane in the atmosphere by increasing rice production will lead to an increased temperature even after you stop.

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

#263

Post by arghwhat »

AmericanChopper wrote: post #245
arghwhat wrote: post #230

Earlier quoted context omitted.

Quoting your linked paper: > Vegetable proteins, when combined to provide for all of the essential amino acids, provide an excellent source for protein considering that they will likely result in a reduction in the intake of saturated fat and cholesterol. > [..] When the more accurate PDCAAS scale is used, soy protein was reported to be equivalent to animal protein with a score of 1.0, the highest possible rating (Ha…

You could revise your claim that vegetable proteins are just as good as animal sourced proteins, to the far more specific claim that soy proteins being as good as animal proteins if you like. Because soy is the only plant source that is comparable in quality to animal sourced proteins (which is why the majority of vegan protein supplements are soy-based). Even then, if you were to get all or a majority of your protei…

No, my claim that vegetable are a good source of high quality protein in general - and not just soy - is taken straight from your paper. You are cherry-picking data and ignoring the most basic dietary advice to support your pro-beef argument at this point. Not only that, you are adding completely bogus claims such as to the amount of food required from sources you find inferior: A steak contains roughly 25 grams of protein per 100 gram. Boiled soy contains 17 grams of protein, while dry roasted soy contains 40 grams of protein per 100 gram - almost double that of beef. Someone weighing 80kg would need eat 240 grams of steak, 352 grams of boiled soy, or just 150 grams of dry roasted soy! Not only are the numbers similar, but they are beat by soy yet again.

And yet again, basic dietary advice is that you should eat varied. Suggesting that you should cover your entire nutritional requirements from a single source - steak, soy or anything else - or in a single serving is objectively bad advice.

As a proud carnivore who has difficulty finding comfort in vegetarian diets, I find this sort of backwards justification for our environmental load highly disappointing. Eating meat is one thing - as a steak lover, I would be a hypocrite to fault you for that - but trying to make it sound like a necessity or a sensible choice is just... Wrong.

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

#264

Post by Timon3 »

Retric wrote: post #261
Timon3 wrote: post #249

Earlier quoted context omitted.

Rice cultivation hasn't been a factor in climate for all time, only relatively recently. The increase in methane can have an accumulating warming effect. Think about it like this - the amount of rice fields is the derivative of climate change. If you increase the amount of rice fields once and don't decrease it, climate change will slowly but surely rise, even if rice fields don't increase.

10,000 years isn’t relatively recently on the scales of human civilization nor how quickly the climate feedback loops operate.

Okay? I don't see how this is relevant? All I was saying was that there was a point in time without rice cultivation, and another one with rice cultivation. The point with cultivation has higher levels of methane. Even if you were to return to the point without cultivation, the period with cultivation will have lead to an increased temperature.

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

#265

Post by cmrdporcupine »

colechristensen wrote: post #209
cmrdporcupine wrote: post #93

Earlier quoted context omitted.

Without yearly tillage (or herbicide spray in case of no-till), weed mgmt is going to be tricky for perennial cash crops. It's certainly tricky for e.g. vineyards and orchards. I suppose with rice (or kernza wheat) you could use a selective broadleaf herbicide. Doesn't help with invasive grasses.

Herbicides are all generally sprayed when the crop is alive and growing anyway, there’s really no new challenge there

Regimen often includes cover crop then burn down herbicide (and/or tillage) before planting.

I am 100% in favour of perennial crop agriculture, but this is going to present entirely new weed mgmt problems for the kind of industrial scale cash crop agriculture this is apparently for. Annual planting gives the farmer a chance to manage weeds (and soil structure etc) every planting season.

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

#266

Post by JamisonM »

hinkley wrote: post #178
JamisonM wrote: post #78

Earlier quoted context omitted.

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,…

Thanks for info, neat!

Most problem weeds on the prairies where I farm are taller than the planted crops when mature, particularly as yield benefits have been gained by shortening more and more varieties over time. A pigweed or a smartweed will outrun a wheat crop with a week of head-start like nothing. Corn can't take any competition at all, I had a planter row in my Barley of corn one year, I figured the corn would simply outgrow the barley and leave it in its proverbial dust.. quite the opposite, I sprayed the Barley out at about the 4-leaf stage and the corn was a full 2 feet shorter than the row beside it at maturity!

That all said of course a natural prairie is different, the tall-grass prairie - as far as I understand it - competes for water under the ground more than light above it - shade can actually help! (Lord knows I mow under my trampoline twice as often as the rest of the lawn.)

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

#267

Post by contingencies »

throwaway2037 wrote: post #238
numpad0 wrote: post #229

Earlier quoted context omitted.

Rice planting machines exist, doesn’t look much different from home lawnmowers. IIRC, in spring farmers make a batch of rice sprouts on disposable cups, load them into this, and it lays them down as the old man drives across his field back and forth. 0: https://youtube.com/watch?v=uS54w2ZH-OE

Anywhere that is rich enough uses these rice planting machines. You see them frequently in Japan, Korea, Taiwan, etc.

I believe "flat" rather than "rich" is more of the limitation. Machines cost almost nothing in China, but the access or field topography very often makes them untenable.

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

#268

Post by Retric »

Timon3 wrote: post #264
Retric wrote: post #261

Earlier quoted context omitted.

10,000 years isn’t relatively recently on the scales of human civilization nor how quickly the climate feedback loops operate.

Okay? I don't see how this is relevant? All I was saying was that there was a point in time without rice cultivation, and another one with rice cultivation. The point with cultivation has higher levels of methane. Even if you were to return to the point without cultivation, the period with cultivation will have lead to an increased temperature.

It’s relevant because you said relatively recently then chose a completely arbitrary yet undefined point. Once you start talking about periods before written or oral records we have little basis for comparison to say if it was good or not. Why not chose the last ice age, or even periods with higher than current global temperature as the baseline?

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

#269

Post by ramblenode »

jimnotgym wrote: post #232
ramblenode wrote: post #197

Earlier quoted context omitted.

This is a kind of "wronger than wrong" fallacy [0]. Yes, not all pasture land is suitable for cereal crops. But that doesn't negate the fact that most livestock production does present an inefficient tradeoff when optimizing for nutrition and land/climate impact. This is because a) a large portion of cereal crops are diverted to feed livestock and b) very little livestock comes from natural pasture land. So only a mi…

Of course your point a is true, but it doesn't need to be. In other parts of the world cattle are not fed on cereals at all, or minimally. Equally cereal production has been a major cause of native grassland being plowed up, with much of the biomass turning back into CO2. If it were turned back to pasture it would begin to sequester carbon again. Grazing animals could be grown on that pasture, but not at the intensit…

The problem is that most pasture is not natural; most of it was converted from forest at some point. In that way it is still an environmental tradeoff.

Pasture doesn't really sequester carbon either, and grazing is still a big net GHG emitter because of methane (more potent than C02).

Forest, on the other hand, sequesters carbon, produces oxygen, and creates microclimates that are more hospitable to humans and which buffer against extreme weather changes.

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

#270

Post by Retric »

Timon3 wrote: post #262
Retric wrote: post #260

Earlier quoted context omitted.

That’s true, but we’ve been cultivating rice for thousands of years. When people talk about returning the earth to pre industrial levels that’s a world with significant rice cultivation going back long enough to account for such differences. The global energy imbalance is simply lag before temperature’s equilibrium, when you turn up the heat in your house it takes longer to heat your fireplace than a wood door. That…

> That’s true, but we’ve been cultivating rice for thousands of years. How much rice did we previously cultivate, and how many of those fields were flooded? Around 1900 the world population was around 2 billion, so I feel confident in assuming that we've since strongly increased the amount of farms. As such I don't see how this matters. Cultivation is not a boolean state. > The global energy imbalance is simply lag b…

> Around 1900 the world population was around 2 billion, so I feel confident in assuming that we've since strongly increased the amount of farms

Actually not so much, due to vastly increased agricultural output per acre the tendency is to have less acres under cultivation. https://www.statista.com/statistics/196104/total-area-of-lan...

Further agriculture has also reduced quite a bit of methane production by draining swamps etc. So it’s difficult to do direct comparisons even just back in 1900.

> Increasing the amount of methane in the atmosphere by increasing rice production will lead to an increased temperature even after you stop.

That’s true of CO2 across the next few decades but not methane because it breaks down so fast. Assuming net zero CO2 the lag would be in the other direction where it would get colder for several years after you stopped.

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