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Perennial rice: Plant once, harvest again and again

npr.org

21–30 of 296 posts

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

#21
Won't yields go down eventually as the soil becomes more and more degraded as the same nutrients are extracted?

I'm assuming you need to find a way to make up for that. Something that's hard to do if you think about how grain is planted. Can't really drive over it with a tractor once it has a certain height. Even if you take off only the parts you need and leave the rest in place.

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

#22
Abstract from the Nature Sustainability paper:

From a single planting, irrigated perennial rice produced grain for eight consecutive harvests over four years, averaging 6.8 Mg ha−1 harvest−1 versus the 6.7 Mg of replanted annual rice, which required additional labour and seed. Four years of cropping with perennial rice resulted in soils accumulating 0.95 Mg ha–1 yr–1 organic carbon and 0.11 Mg ha−1 yr−1 nitrogen, along with increases in soil pH (0.3–0.4) and plant-available water capacity (7.2 mm). Perennial cultivars are strongly preferred by farmers; growing them saves 58.1% of labour and 49.2% of input costs in each regrowth cycle. In 2021, perennial rice was grown on 15,333 ha by 44,752 smallholder farmers in southern China. Suited to a broad range of frost-free environments between 40° N and 40° S, perennial rice is a step change with potential to improve livelihoods, enhance soil quality and inspire research on other perennial grains.

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

#23

(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…

The aviation sector is about 2%.

Sounds like another premature optimization problem, as applied to climate change.

“Premature optimization is the root of all evil“

https://wiki.c2.com/?PrematureOptimization=

What about coal?

What about coal?

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

#24

Won't yields go down eventually as the soil becomes more and more degraded as the same nutrients are extracted? I'm assuming you need to find a way to make up for that. Something that's hard to do if you think about how grain is planted. Can't really drive over it with a tractor once it has a certain height. Even if you take off only the parts you need and leave the rest in place.

You still need to add fertilizers that's not what this is about. (And you absolutely drive over crops with tractors)

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

#25
post #23

(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…

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

The need to eliminate coal emissions does not preclude the need to eliminate emissions from other sources.

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

#26
post #23

(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…

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

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.

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

#27
post #23

(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…

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

Emissions reduction isn't the goal, it's a nice side effect of this. Not needing to replant every year is the reason for using this rice.

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

#28

Abstract from the Nature Sustainability paper: From a single planting, irrigated perennial rice produced grain for eight consecutive harvests over four years, averaging 6.8 Mg ha−1 harvest−1 versus the 6.7 Mg of replanted annual rice, which required additional labour and seed. Four years of cropping with perennial rice resulted in soils accumulating 0.95 Mg ha–1 yr–1 organic carbon and 0.11 Mg ha−1 yr−1 nitrogen, alo…

> accumulating 0.95 Mg ha–1 yr–1 organic carbon and 0.11 Mg ha−1 yr−1 nitrogen

importantly, this should reduce the need for fertilizer to replenish soil nitrogen

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

#29
post #23

(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…

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

This is not an either/or thing.

Germany emits 2% of all CO2, not worth us doing anything then?

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

#30
post #23

Earlier quoted context omitted.

The aviation sector is about 2%. Sounds like another premature optimization problem, as applied to climate change. “Premature optimization is the root of all evil“ https://wiki.c2.com/?PrematureOptimization= What about coal? What about coal?

The need to eliminate coal emissions does not preclude the need to eliminate emissions from other sources.

I suppose if we didn’t wait decades to eliminate the big problems, we’d have more time to worry about the smaller problems.

A 100 years of coal emissions is 1000 years of rice.

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