(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 soil degrades. This flooding is mostly used to control for weeds, but weeds have a much more difficult time competing when a perennial canopy already exists.
So, perennial rice may end up reduce GHG emissions substantially.
I hadn't heard about rice fields emitting methane before. I was able to quickly find an article, "Methane emissions from global rice fields: Magnitude, spatiotemporal patterns, and environmental controls"[0], which states:
> Our study estimated that CH4 emissions from global rice fields varied from 18.3 ± 0.1 Tg CH4/yr (Avg. ±1 SD) under intermittent irrigation to 38.8 ± 1.0 Tg CH4/yr under continuous flooding in the 2000s, indicating that the magnitude of CH4 emissions from global rice fields is largely dependent on different water schemes.
At 18.3-38.8 Tg CH4/yr, this estimate comes out to about 500-1500 million tons of CO2-equivalent per year according to an EPA GHG-equivalence calculator[1]. Global emissions are estimated at north of 34 billion tons of CO2-equivalent per year[2], putting the total CO2-equivalent from rice fields throughout the world at 1-3% of total global emissions.
To put this into context, animal agriculture is responsible for 18% of the worlds CO2 emissions, uses 83% of the world's farmland, but only produces 18% of our calories and 37% of our protein.
I really wish there was a name (that I knew of) for this logical fallacy of using precise quantities of meaninglessly confused categories.
What do you think "farmland" is ? Our ancestors who knew how to raise cattle and farm cereals for millennia were surviving on the verge of starvation : why do you think that was ? Were they so dumb they'd rather die of hunger than convert some of their grazing pastures to cereal agriculture ? Or some "farmland" can be used for grazing but not for agriculture, maybe ? Same for proteins : all amino acids are not equal, a a pound of soy protein won't have the same effect on your body as a pound of meat proteins. And don't get me started on nutrients and their bio availability (e.g. iron and B12).
As far as CO₂ emissions from cattle, where do your think the C comes from ? The grass/food that cattle eat, what would happen to it if let to decompose ?
Yes, some land is not suitable for agriculture. No, this does mean that having cattle is a neutral usage as each cattle requires agriculture to feed for 3-4 years before they are slaughtered.
Yes, cattle emissions are largely from the food. No, this is not just grass that was already there and would decompose anyway - the majority of agricultural production is to feed cattle and would not be necessary without (the efficiency of raising an animal for years to get a few steaks is horrible), and even if fed naturally it significantly increases the rate of plant turnover.
Yes, meat protein is a great source of nutrition. No, it is not magically better than equivalent vegetarian nutrition. Both have diets ranging from super healthy to obesity inducing. Being carnivorous or vegetarian is itself not a significant health factor - chips and crisps are often vegan, and Big Macs contain meat.
> Yes, meat protein is a great source of nutrition. No, it is not magically better than equivalent vegetarian nutrition.
It’s not magic, but the protein from animal sources is just scientifically better than protein from plant sources. If you want to compare the nutritional benefits of different protein sources you need to account for how bioavailable they are. Some plant sources aren’t bad, but none are as good as animal sources, and some of the them aren’t very good at all.
> 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 (Hasler, 2002).
> Soy is a complete protein with a high concentration of BCAA’s.
So not only does the paper say that soy protein is a "complete" protein like beef, it scores soy higher than beef in Table 1 (which only gets a score of 0.92!), and states that it has associated health benefits (several mentioned throughout the paper).
Whey also scores a 1.0 for the curious, suggesting we do not have to eat the cow to get its protein.
Furthermore, it should be noted that the paper studies protein uptake efficiency and coverage ("quality") in the context of elite athletes and their very high protein requirements that range from difficult to dangerous to maintain (the paper mentions concerns of cardiovascular issues and bone loss risk when using beef protein for example). These concerns do not apply to those without extreme dietary needs.
Even if you cannot eat soy, the concerns of coverage or quality of individual protein sources are largely irrelevant when combined with a varied diet that contains more than one source - arguably a requirement to discussing dietary health, and suggested by the paper as a solution.
So while the reference to the paper is good, it is important to read it - thoroughly - in its intended context.
Complete protein or not, you can get your sulfur-containing amino acids 32oz of tofu or 6oz of turkey (less of both if you're smaller), and other vegan sources are significantly worse, so a properly varied diet has higher demands. It's not impossible, but it's not as easy as just replacing all your animal proteins with equivalent masses of plant proteins either.
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 protein requirements from soy, then that's a lot of soy. You'd have to eat 1-2 pounds or more of boiled soy beans per day. Which aside from being a very atypical diet, would also be above the level of isoflavone consumption that has been studied to be safe (incidentally, consuming large quantities of whey protein also has some unpleasant side-effects in most people, like extreme flatulence, constipation and the associated discomfort).
Implementing a highly restrictive diet, that eliminates entire food groups that you've evolved to rely on, is unsurprisingly complicated. It also unsurprisingly puts you at risk of deficiencies in the nutrients that your new diet is deficient in. Which is why vegans are unsurprisingly at an increased risk of negative health outcomes associated with those deficiencies.
Your claim that vegetable protein is just as good as animal protein is honestly just misinformation, as well as being dangerous health advice. You can eat a healthy vegan diet if you put the effort into planning it properly, which anybody following your erroneous advice would not be doing.
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.
That paper would suggest to me that perhaps eggs are as animal as we need to get. I agree with your specific point here, but it feels like a small thing when considering the overall societal and environmental cost of animal protein (esp. beef, pork, lamb).
If you tried to get all your calories from eating eggs, your diet would have too much fat and not enough carbs. In reality you need a balanced and varied diet, and the world couldn’t support 7 billion people all deciding to get their protein intake from one specific food item anyway. Animal products are simply better at providing the protein you need. You _can_ get all of it from plant based sources (I’m not sure whether it would be theoretically possible for all humans to adopt such a diet), but it’s more difficult. Meaning if you want to meet your nutritional requirements without having a big calorie excess, you have to plan your diet very carefully, and implement a highly restrictive program. If you want to do that without eating highly processed foods such as soy protein isolate (which is a popular dietary restriction), then you’re going to have an even harder time.
That depends on whether you care about eating too many calories. If your average person got all their protein from eggs, they’d eat too much fat, way too much saturated fat, and have very few calories left to get in all of their other nutritional needs.
Incidentally, that’s why it is possible to eat a healthy plant based diet if you’re very active. If you burn 2000 active calories a day, then it matters less if you’re eating nutritionally inefficient food, because you can make up for it in volume.
I'm not arguing for some sort of protein gruel or standard diet; my comment wasn't advocating for "only eggs", just reacting to what you share.
I am stating that it seems inarguable to me that the benefits of meaningfully reducing or even eliminating animal consumption far outweigh the negatives (note: I'm not a vegetarian). The concerns about protein completeness are real, but they have to stand in the sunlight of the full picture, and when viewed that way it doesn't appear to be some unsolveable riddle.
So I'm not arguing the point, I'm arguing against the implicit takeaway that comments like yours can appear to make: that meaningfully reducing or eliminating animals from our diets isn't a goal worth pursuing.
My SO and I reverted to omnivore for health reasons. Basically Dr Wahls' "Minding You Mitochondria" thesis. Still eat a lot of rice and beans. But now make sure to get a minimum amount of meat too.
I'm so eager for vat grown protein. But only if it has the same macronutrients as real meat.
> Our ancestors who knew how to raise cattle and farm cereals for millennia were surviving on the verge of starvation : why do you think that was ? Were they so dumb they'd rather die of hunger than convert some of their grazing pastures to cereal agriculture ?
This is one of those "not even wrong" kind of things. The conditions that led to famine-cycles plaguing the Old World until the arrival of New World crops, and later the Green Revolution, have nothing at all to do with modern farming or land use, not even in the way you're trying to make the connection. This is all just completely irrelevant to the point you're trying to use it to make.
"Were pre-contact old-world farmers just too dumb to kill their cows so they could plant more wheat and stop starving every few years?", asked rhetorically to imply that reducing meat farming can't possibly help with any modern problems. I mean... it's just a nonsense question, the context they were operating in, the global population size, and their farming practices are so far removed from what we do now that it doesn't make any sense to frame it this way. No, they weren't too dumb to think of that, and no, it wouldn't have helped if they had tried it, but neither of those things are relevant to the modern situation, at all.
> a pound of soy protein won't have the same effect on your body as a pound of meat proteins.
True. Eating meat will raise your inflammation markers by 70%.
> nutrients and their bio availability (e.g. iron and B12)
Fe3 from animal sources has a better uptake by the body. Fe2 from plants is good enough if you combine it with Vitamin C. Parsley contains both.
Animals in conventional agriculture have to be fed B12, for them to stay healthy and their meat to contain any. The B12 producing bacteria in
the soil get killed by pesticides.
The 83% of farmland which is used to feed and raise animals taken together is the size of Africa.
Source: Game Changers, the movie [0]. Highly recommended, stopped cooking wirh organic meat, i take B12 directly instead. If someone else cooks for me, i still eat meat and enjoy it. Knowing full well that it damages my body, like alcohol and sugar. Completly banning fun sounds awful.
"Game Changers" is a terrible place to plant your fact-flag. Like all documentaries of its type, there is no balanced fact-checking, questionable "experts" basing their opinions on small inconclusive studies, etc, etc.
> Eating meat will raise your inflammation markers by 70%.
Big claim. Can you provide a source for this? [Updated, if your source is a movie, is not a real source and is useless. People fly in the movies]
In any case to avoid falling in a tunnel vision spot we would need a comparison with the effect of vegetable pesticides on inflammation markers also.
We humans, eat meat since... forever in our history. After that idea ancient people should have inflammation markers skyrocketing so could be easy to check it. Have you consider the possibility that the problem could be other than the meat like for example diesel contamination or plastic wrappings?
Watch it if you can, it has a lot more on offer. I ate meat before i saw it, since i need B12. Now i rarely do, usually when someone else cooked for me.
> True. Eating meat will raise your inflammation markers by 70%.
I'm going out on a limb here, but I would think that the average vegetarian is going to be much more health conscious than the person buying a steak and 24 pack of Bud Light every Friday. I haven't watched the doc - is this mentioned?
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 miniscule percent of livestock production represents no land use tradeoff whatsoever.
a) 40% of cereal crops go toward animal feed [1] and most modern animal agriculture would be impossible without this. Arable land that could be feeding humans is being used to feed animals which then feed humans. That represents roughly a 90% loss of potential biological productivity [2].
b) Despite the US having some of the largest natural pasture, only 4% of retail beef in the US is grass-fed--meaning only a tiny percent are fed exclusively from pasture [3]. Additionally, most pasture land has been converted from forest. 40% of deforestation overall is due to animal agriculture [4]. This is only a little less than plant-based agriculture which provides sinificantly more food.
I think one of the bigger questions than "why does the US raise so much livestock" is "why doesn't the US raise bison & buffalo instead of cows"?
I'd imagine a lot of the US' livestock needs could be handled by just re-wilding pasture lands with native plant and animal species (including bison). And just as a guess I'd imagine it'd be more sustainable than trying to raise cows.
If we needed less land to feed humans we could instead use the land to sequester carbon and provide habitats for wild animals, e.g. by planting forests.
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 intensity of a US factory farm.
The answer is that the system is complex and there are no easy fixes.
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.
Hang on a minute, 'most' pasture might not be natural, but no arable ground to grow the alternative food is natural at all! And even if 'most' pasture is not natural we should not ignore that significant pasture was natural. Lets take the Great Plains of North America as an example. Ploughing it up to turn it into arable land was not natural and released much carbon.
> Pasture doesn't really sequester carbon either
Simply untrue. In the UK if I had pasture land I could even get paid for the carbon I had added to the soil. Here is a nice quote that says the complete opposite of your unreferenced comment:
"Prairies have the ability to store as much carbon below the ground as forests can store above the ground. When carbon is stored below ground it will remain locked there and be unable to enter the atmosphere."
I think you are making the same mistake as everyone else by pretending there is a simple solution. Special interest groups, like those who are dogmatically opposed to meat production, are twisting the science just as much as their opposition is.
Certainly some cattle are grazed on land that would be too hilly / rocky etc. to farm. And that's not a terrible use of land, but enormous numbers of cattle are raised in feedlots, and fed cereal crops like corn (maize) which have to farmed on the better farmland, which is far less reasonable.
The non-arable land meme comes from a paper that considered land non-arable if it had 25% crop yield (due to things like bad soil or too rocky or too much of a grade). Yet the things that make land non-arable also reduce their yield for animal ag on that same land.
“The grass/food that cattle eat, what would happen to it if let to decompose ?”
It would decompose (once) and then natural habitat would return because we need less of that land, capturing carbon more permanently because it’s released more slowly. In Brazil, exactly the opposite is happening: deforestation to feed cattle. Are you arguing for that deforestation?
Not the same user but I will argue for deforestation any day. Humans are grassland creatures and trees are our enemy. Trees shadow the grass and affect our natural habitat. Even elephants know this and get rid of trees when they see them. [1]
In fact, when the wooly mammoths went extinct, Pleistocene Park turned from a grassland to a forest, and now an ecological disaster [2].
That's just dump. If you really want to over simplify human history, we are Savanna creatures, and Savannas contain plenty of trees and other perennial plants. I also don't get why you are bringing elephants into this, especially because there are whole sub-species of elephants that are adapted to forest-dwelling.
As are humans, by the way. Plenty of human civilizations have historically specialized to live in heavily forested biomes, ranging from the rain forests of the tropics to the boreal forests in northern Europe, the North America and Asia. Agroforestry as a practice goes back thousands of years in both the old and the new world.
>I also don't get why you are bringing elephants into this
Because trees are invasive plants and elephants keep them out of the grassland ecosystems.
>especially because there are whole sub-species of elephants that are adapted to forest-dwelling.
Yes, trees did win that battle... potentially because of sudden drop in elephant population because of disease or famine... but it doesn't have to be the case everywhere.
>Savannas contain plenty of trees and other perennial plants.
This is a cause for concern and it is a direct result of the drop in African elephant population from several million to around half a million now.
> As far as CO₂ emissions from cattle, where do your think the C comes from ? The grass/food that cattle eat, what would happen to it if let to decompose ?
I don't know about other countries, but the percentage of meat in the U.S. that comes from cattle roaming pastures and eating grass is very small (because it costs so much more).
A lot of grazing is done on marginal farming land. For example land that is very dry or land that is very steep. So generally a statistic like 83% of the world's farmland doesn't make any sense.
Not sure if it is possible to count factory farming properly- that takes really good farmland and sends the production to animals.
> A lot of grazing is done on marginal farming land.
For example, New Zealand: ~55% is being used for sheep and cattle, and only ~2% of NZ is arable (see https://youtu.be/F_g6-4swJ_s at 14:45) with a major part of the reason why explained near the 10:00 mark (weather in South Island).
That “farmland” number is next to meaningless. The vast majority of animal land is useless for other agriculture. If you are visualizing a green grassy field full of cows, that is nice and they might even support one cow per acre (2/hectare). Those area numbers are completely swamped by the huge areas you don’t see where someone is grazing one skinny cow per 200 acres (100 hectares) of high desert.
A more useful number might discount the grazing/fodder lands which are not useful for other agriculture.
What % of farmland used for meat production is actually usable for something else? I don't think cattle grazes on prime land, or even mildly productive land.
It really depends on what you define as "usable". I am currently looking out of a window in the Bavarian Forest and see nice lush green meadows which would be perfectly productive under many different types of crops, but which are mostly used as pasture and meadow for hay production, because the landscape is hilly, which isn't well suited to be farmed with the heavy equipment that has become standard in i.e. corn and wheat production. This type of heavy, industrialized equipment in turn has been a type of farming heavily supported and subsidized by current agricultural policies. You could change the incentives and bring a lot of the farmland currently considered "marginal" into crop production again.
Currently less than 1% of the population in many industrialized countries are working in agriculture. That is laughably few people and there is no reason why it couldn't be a greater share of the population. Guess what: many people are actually enjoying this kind of work when it isn't presented in a context of total exploitation.
And no, while agriculture certainly tends to be physically demanding, it is not unreasonably so, even when done at small scale and with smaller machines. Small scale agriculture has been mechanized to a large degree and mechanized solutions have even been developed for very sustainable approaches to agriculture like agroforestry and syntropic agriculture.
I would have expected comments about AI and robotics instead. If you can build terraces and farm them robotically, then you can reuse the technology on Mars.
I imagine they're using "our" in the global sense. Virtually no one is truly dependent on meat for protein; the food the livestock eat are probably mostly human-edible and offer sufficient protein on their own. There's minimal nutritional value added by the meat production process.
Failing to control for nutritional quality also makes those numbers very misleading. For example that 37% of protein would translate to more than double that number based on bioavailability for humans, and meat is far more nutritious than grains (and many vegetables).
The whole "plant based" thing is based on the simplified Wall Street model of food based on misunderstanding of nutrition. For their purposes, protein and fat are just protein and fat whether they come from meat, milk, eggs or dairy... or if they come from grass seeds. If that was the case, it would make sense that we replace ALL animal agriculture with grain farming. Grains can practically be transported and stored for years very cheaply.
Unfortunately, plant foods do not provide us the necessary nutrients. ALL human civilizations and tribes had animal foods as a part of their diet. There is not a single tribe that survived on plants alone.
So, even if 99.99% of "farm land" was required for animal agriculture, we'd have to keep it that way.
It's a similar problem with hydroelectric dams. If you drown a biosphere, then methane is a product of anaerobic decay. So it's a question of how much material is there to decay, and what fraction of that decay is oxygen deprived, so that it can't fully oxidize the C-C, C=C, and C-H bonds to water and carbon dioxide.
This is a bit overblown. The methane being emitted is sourced originally from atmospheric CO2 via photosynthesis, 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.
This is fundamentally different from natural gas emissions, in which carbon atoms are being transferred from stable geological reservoirs into the atmosphere, where they increase the CO2 levels after the methane is oxidized.
There are also other risks to switching to this cultivation method:
> "Researchers note potential risks. Because PR23 enables farmers to till less, fungi and other pathogens can build up in the fields. Insects can persist in the stubble after harvest, because it’s not plowed under, then transmit viruses when they feed on the regenerating sprouts in the spring. And without tilling, weeds can flourish; the researchers found that fields with PR23 needed one to two more herbicide treatments than regular rice. They also note that it’s more work to resow the perennial rice when its yield falters, because its larger and deeper roots need to be killed."
Atmospheric methane has a half-life of about 10 years and is well over 10x as greenhouse effecting as CO2. Converting atmospheric CO2 to atmospheric methane is less bad than releasing sequestered methane into the atmosphere but still terrible.
> Converting atmospheric CO2 to atmospheric methane is less bad than releasing sequestered methane into the atmosphere but still terrible.
Sure, if this conversion led to more and more methane in the atmosphere, it would be terrible. In this case, however, the overall amount of methane in the atmosphere due to rice will stay the same, since it's a cycle.
It's all about cycle length. CO2 from shallow ground cycles into the air, then it quickly cycles back into the ground. The forest burns, the forest regrows. CO2 leaves, CO2 returns.
Fossil fuels are also a cycle. We bring up the fossil fuels from deep ground and a million years later that CO2 returns to deep ground. That's a long cycle, that's a problem.
Isn't it the case that a lot of fossil fuels were biomass accumulated in a time before microorganisms had evolved to be capable of digesting woody plants and so are largely non-repeatable because the circumstances which can lead to coal are now narrower?
> 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).
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 preindustrial levels (comparable to 20 ppm CO2), likely from the expansion of human agriculture, more cows, maybe forest removal.
We're locked into it now due to permafrost melt and increased rainfall in to the tropical belt, swapping out one strain of rice for another will have marginal effects at best.
> "NOAA scientists are concerned that the increase in biological methane may be the first signal of a feedback loop caused in part by more rain over tropical wetlands that would largely be beyond humans’ ability to control."
The tipping point has come and gone, we're heading for the Pliocene. Plan accordingly.
> 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).
No, this is incorrect. The number you cite (25x) is a 100-year global warming potential (GWP) figure. That is, if I release 1 ton of methane into the atmosphere today, over the next hundred years it will contribute to global warming about as much as if I'd released 25 tons of CO2.
But this is not an appropriate way to analyze the composition of the atmosphere at a point in time. We're not releasing 1.9 tons of methane and 420 tons of CO2 and looking at how that will effect global warming over the next 100 years. Instead we're looking at the CO2 that has built up over the past few hundred years, and the methane that has built up over the past few decades, and looking at how that affects global warming now. We want to integrate over past contributions and look at the resulting warming at a point in time rather than look at emissions at a point of time and integrate over future warming.
The effect of methane when you look at it this way is much higher. The IPCC estimates[1] that methane radiative forcing (i.e
contribution to global warming at a point in time, based on current atmospheric concentration) is about 0.48 W/m^2, vs. 1.82 W/m^2 for CO2. That is, the ratio of (warming due to methane) to (warming due to CO2) is about 1:3.8, not 1:8.4 (50 ppm:420 ppm from your calculation). More than twice as bad as the calculation based on GWP!
The good news is that since methane has a short half life, if we can cut methane emissions that portion of the total radiative forcing will respond quickly (1-2 decades). Cutting CO2 emissions takes much longer to show effects.
Look, the only plausible route to stabilizing the atmospheric chemical composition is to stop pumping carbon out of geological reservoirs into the atmosphere.
That's really all there is to it, you have to eliminate fossil fuels from the system if you believe climate change is a real issue.
Of course, at this point, even that won't stop the climate from steadily warming for the rest of your life, i.e. for the next 100 years at least. The trigger has been pulled.
I advise against buying property on the coasts, in flood plains, etc.
> 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 organic matter in flooded fields decompose, released carbon atoms have been captured only a couple of months or years earlier.
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.
That’s very misleading because Methane is extremely front loaded in its effects. Year 0 is very bad year 50 is only equal to the amount of carbon in that methane. As rice farming is very consistent year to year, and rice removes carbon as it grows the net effect on future warming is ~zero because all the previous years have already been baked in to current conditions.
The great news is reducing Methane from existing sources is one of the fastest ways to reverse climate change after we reach net zero.
That math isn’t mathing. With the rice field active, there’s more methane in the atmosphere every year, compared to the world where the rice field doesn’t exist.
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.
No, that’s not the case, because the methane doesn’t accumulate. If you increase the amount of rice under cultivation, the methane content in atmosphere will stabilize after around 20 years, and after that there will be no more climate change resulting from the rice fields.
I'm not saying the methane accumulates, but the additional energy in the whole earth system does. Every year with additional methane has an effect. If you have no rice fields, then rice fields for a couple of years, and then again no rice fields, you'll have increased methane levels for those years. If you compared that earth to another one without those years of increased levels, the one without would be less warm.
Remember: climate change is not a derivative, it's an integral.
No, the energy doesn’t accumulate in Earth over time. Disregarding the energy of radioactive decay within Earth, the Earth is in steady state with respect to energy. 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.
> If you compared that earth to another one without those years of increased levels, the one without would be less warm.
No, after the methane from the fields decays to CO2, both would be the same.
> 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 has been rising since more greenhouse gases were introduced: https://www.nasa.gov/feature/langley/joint-nasa-noaa-study-f...
The amount trapped is rising because we retain the same input longer. A fraction of the total heat is radiated away (not all of it, and not "rather quickly"). If that fraction drops more heat will be trapped.
Now you have a system with additional energy due to additional greenhouse gases. Over time the gases will reduce, but the radiation is still only a fraction of the total heat! Of course over time this will very slowly trend back towards the same temperature, but even when the gases themselves have returned to previous levels, the additional heat will take a number of years to be radiated away.
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 same effect takes longer on the scale of the earth but it’s an exponential decay. Compared to the history of rice cultivation you very quickly get to millions of a degree difference in surface temperatures. We just keep adding ever more greenhouse gasses.
> 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.
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.
> Actually not so much, due to vastly increased agricultural output per acre the tendency is to have less acres under cultivation.
Your source shows data for America between 2000 and 2022. Why do you think that is a good source for the topic at hand?
> 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.
There is no reason to do so, my argument is not affected by it in any way.
> That’s true of CO2 across the next few decades but not methane because it breaks down so fast.
No, breakdown time doesn't affect anything, since I'm specifically talking about the time after it broke down. If you understood my comments differently, try re-reading them in that light.
> Assuming net zero CO2 the lag would be in the other direction where it would get colder for several years after you stopped.
Am I understanding you correctly - you believe that temperature is like a pendulum, where after a period with increased greenhouse gases, it will somehow swing to be colder than it would have been without that period? Why do you think so, and how do you believe this to work from a thermodynamics perspective?
> Why do you think that is a good source for the topic at hand?
The obvious downward line even as population and farm output increased prove your argument was completely false. That’s as much as I care to prove. Do some damn research.
> Am I understanding you correctly - you believe that temperature is like a pendulum, where after a period with increased greenhouse gases, it will somehow swing to be colder than it would have been without that period? Why do you think so, and how do you believe this to work from a thermodynamics perspective?
Hell no. I am saying if the level of greenhouse gasses drops there will be lag in the other direction. There’s nothing special about the direction of lag it’s simply a delay before equilibrium.
Clearly you haven’t understood what I said or the topic at hand and need to do some actual research before you keep spouting more nonsense.
> The obvious downward line even as population and farm output increased prove your argument was completely false. That’s as much as I care to prove. Do some damn research.
"The obvious downward line" is not relevant since it's for a time period that is only starting to affect todays climate. I was previously talking about time periods which would already be affecting the climate today. What if through the use of modern machinery and fertilizer the land use started trending down slightly in the 80s, and rose rapidly before then? We don't know, which is why your statistic is fully irrelevant to this discussion. I'm not interested in simplifying complex systems like historical agriculture to "line goes down now, line must have been going down before".
Maybe "do some damn research" that looks at the content in the context of the discussion.
> Hell no. I am saying if the level of greenhouse gasses drops there will be lag in the other direction. There’s nothing special about the direction of lag it’s simply a delay before equilibrium.
I really, really think you should try to re-read my previous comments. This doesn't make any sense. Let's play through it with numbers - maybe you'll show me I've been a complete idiot.
Let's define a starting point of greenhouse gases and temperature, both start at 0. We are in an equilibrium. Now we increase greenhouse gases to 1, and after some time temperature will also increase to 1 (arbitrary values). Then we decrease greenhouse gases to 0 (previous equilibrium). It will take some time until the temperature goes back to 0.
Referring back to the comment I was replying to: where do we get colder compared to a reference earth without increased gases?
That's my whole argument, it's what I've been writing the whole time. The increased greenhouse gases lead to a higher temperature, which will (until it goes back to equilibrium) be increased compared to if there was no increase in greenhouse gases, and it will stay increased for a while after greenhouse gases are at equilibrium.
What exactly are you arguing against? It seems you're taking stabs at whatever sentence you feel is incorrect, but I haven't seen a coherent argument.
More complaining zero research, why I not surprised…
> where do we get colder compared to a reference earth without increased gases?
Wow. Suppose it’s fall and someone says “the days are getting colder.” Do you assume it’s in relation to some arbitrary point thousands of years ago or last month?
Context is often implied in the written word, and you seem to have issues following normal conventions. I don’t mean this as an insult, but there’s probably some adult education classes that you might find helpful.
If you're not arguing for that, what exactly are you arguing for? What have I said that you disagree with? I've tried laying out my argument multiple times very clearly, but you're choosing to engage in ad-hominems instead. Seriously, what is that last paragraph, if not a giant insult?
I'm trying to have a normal and calm conversation. If you're not capable of responding in kind, don't respond. You're going on about how I'm not doing research, while you're not even responding to my criticism of your previosu statistic. Seriously, if you think that statistic had any value for this conversation: then yes, I'm fully incapable of doing what you consider research.
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?
I stay by that. On a climate scale, scaled-up rice production has started a short time ago - which is why I wrote my initial comment: looking at the climate right now and extrapolating that current rice farming has no impact on climate change is illogical.
Sorry, but what exactly are you arguing for? Of course you can view the climate at different time scales, and of course you can refer to those time scales by colloquial terms. Climate shows cyclic behavior at the time scales I was referring to: https://www.fs.usda.gov/ccrc/education/climate-primer/natura...
You could have asked for what I was referring to, but instead you chose to jump in with your definitions. Have you had conversational success with this approach?
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 now — 150 years after the start of the Industrial Revolution.
By even the most imo insane estimates we are 50-70 years from even minor discomfort. I’m fairly confident we can fix the problem when it becomes a problem
> All the UN data points to a warmer atmosphere equating to more food and higher quality of life.
Globally and to a point, maybe. But that's not taking into account local effects and the millions (billion?) who'll be displaced and what comes with it
Then you have ocean acidification, postivie and negative feedback that we won't be able to stop, &c.
> I’m fairly confident we can fix the problem when it becomes a problem
I’m fairly confident that the same UN data points, and basically the entire corpus of text about climate science, will show you that it's absolutely not how it works because the inertia is way too strong to only care about it when it's in front of you
> All the UN data points to a warmer atmosphere equating to more food and higher quality of life
All data point to countries warmer than Spain having significant drops in life expectancy. Human body is less healthy in a tropical climate than it is in continental climate.
A numbwr of cities will exceed 36 degrees C Wet Bulb Temperature in the summmer. Do you understand what that means? Over heating to death. Sweating does not work any more.
Everyone living in those areas will become refugees.
We are also losing all snowpack. No snowpack means droughts in summer and floods in winter.
Lastly, we expect climate change to cause food shortages. It will not bw just poor countries that suffer. Nations will respond by banning food exports. Britain depends on imported food, it has not been self-sufficient for 100 years
We have no crops that handle high heat well. We neber domesticated perrenial plants properly, they give much lower yields. Perrenial wheatgrass has half the yoeld of wheat.
Potato planta shut down in high heat even if you provide them with water. You can turn the entire field i to soup, at 40 degrees potatoss don't grow.
It is sad that most people do not comprehens the huge cost we will have to deal with this problem.
Last summer we had heat waves and droughts on three continents simultaneously, plus massive unprecedented floods in Pakistan. It doesn't take much to destroy a year's worth of crops, and the IPCC modeling doesn't really come to grips with what we're seeing.
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.
That was actually part of early models of climate change, but we’ve already crossed the point where the negatives from increased CO2 outweigh the positives.
The problem is there are just so many small negatives such as extremely warm weather negatively impacting plant growth. But also less talked about problems like the increase in outdoor CO2 requiring more building ventilation to avoid indoor CO2 levels from giving people headaches. That’s right, global warming actually makes meetings inside air conditioned buildings worse.
I somewhat agree. A climate several degrees warmer than recent history seems like it would be beneficial; in the past, warmer periods coincided with a lush and rich biosphere. More energy is available to life.
Like you, long-term, I'm more worried about the upcoming ice age than runaway global warming. We know how to fix global warming, and will in the next hundred years: Nuclear and solar.
But... warming can still be very disruptive in the short term. Coastlines moving a few hundred feet might be disastrous for entire regions. Staple crops failing in one nation and blooming in another may cause refugees, famine, and war. Politics is local.
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.
Yes, the whole point is that it is a cycle. The fields don’t affect by much the total number of carbon atoms in the atmosphere. Without the fields, other plants would grow there, then die, decay, and release carbon into atmosphere.
At best, growing rice and flooding fields might affect the balance between the amount of methane and amount of CO2 in the steady state, but this is of no practical consequence, because the methane will not accumulate year over year, like the emissions from fossil fuels do.
Suppose we grow twice as much rice as we do now. This means that the steady state will have twice as much methane coming from the fields as it has now. Hell, let’s actually assume that all existing methane in atmosphere is from rice fields, and actually increase amount of methane in atmosphere by a factor of 2. What is the impact to the climate, according to our current models? Well, this is equivalent to less than 10% increase in total CO2 in the atmosphere. That’s like a difference between 2000 and 2020, which is to say, almost unobservable — and remember I assumed we increase total methane by factor of 2, not just methane from the fields.
> but this is of no practical consequence, because the methane will not accumulate year over year, like the emissions from fossil fuels do.
Methane still takes 12 years to break down in the atmosphere, and it's more than 25 times as potent of a greenhouse gas than CO2.
CO2 concentrations are currently ~420 ppm, while methane is ~1866 ppb, or 1.9 ppm. If we assume methane is 25 times worse than CO2, that 1.9 ppm is the equivalent of 48 ppm CO2. Which is gigantic.
Doubling steady-state methane levels in the atmosphere would be a major problem. It would be like CO2 levels going from 468 to 516, yes a 10% increase. I don't know how you can call that "almost unobservable" when we're doing our absolute best to stop any increases. The fact that it's steady state doesn't really matter if it's still a major contributor, and/or if that steady state is increasing.
Thank you for redoing the math I did, and confirming I was exactly correct with figures.
The increase in concentration is observable, but the impact on climate is not. Again: this increase is similar to increase between 2000 and 2020. Without extremely careful and precise measurements, nobody would really be able to perceive any difference in climate between these two dates.
This matters, because it is the perceived effect of climate change that is worrying, not the measured one. Modern science can measure many things with very high accuracy, but these changes only matter if they affect our lives in a way we can perceive. If the change is only seen on accurate scientific instrument, why should the society care much about it?
No, you missed the point: there is an enormous difference between methane emissions from fresh organic matter, and emission from fossil fuels. The latter accumulate, while the former do not. That’s why as we continue incrementally burning fossil fuels, the effects accumulate and affect climate over decades or centuries, but decaying weeds or (fashionable to discuss a couple of years back) cattle burps and farts do not.
The point is that even if it continues over the centuries, the effect of cattle farts and weeds decaying on rice fields will only ever be observable using precise scientific instruments, whereas effect of burning fossil fuels for centuries will be very readily perceivable with very crude techniques.
> the effect of cattle farts and weeds decaying on rice fields will only ever be observable using precise scientific instruments, whereas effect of burning fossil fuels for centuries will be very readily perceivable with very crude techniques
It’s a fine distinction, and I’m glad you made it, but the arguments for why it doesn’t matter don’t stick. Gross imperceptibility does work for any small amount of any emission—there is no way to feel the effect of that emission per se. There is also the case that raising the planet’s steady-state temperature is exactly what existing fossil fuel emissions have done. They’re a problem even if they’re already there.
> but the arguments for why it doesn’t matter don’t stick
I'm not so sure. GP's argument was that when people say rice/cattle release so-and-so much methane into the atmosphere per year, the fact that it's a cycle and the amount of methane & CO2 in the atmosphere due to rice/cattle remains constant is usually ignored.
Meanwhile, burning fossil fuel, increasing air traffic (-> water in the atmosphere), etc. actually increase the total amount of green house gases in the atmosphere, year by year.
Sure, we could think about reducing the constant amount of methane in the atmosphere due to cattle/rice by reducing cattle/rice but, in light of emissions due to fossil fuel accumulating year by year, this doesn't seem to be the most pressing issue by a large margin.
> this increase is similar to increase between 2000 and 2020. Without extremely careful and precise measurements, nobody would really be able to perceive any difference in climate between these two dates.
If that's how you work then nothing has any impact whatsoever, cars, planes, cattle, over twenty years if you split everything in sub categories they're all negligible
Meanwhile we clearly already can measure the effect of it all.
With your logic you're the proverbial boiled frog my friend...
> Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith.
Why unnecessarily double down on this very hypothetical scenario,
> Suppose we grow twice as much rice as we do now. […] Hell, let’s actually assume that all existing methane in atmosphere is from rice fields, and actually increase amount of methane in atmosphere by a factor of 2.
when GP's main point was: Absorption & emissions by rice plants are in a steady state – they emit methane into the atmosphere, it breaks down to CO2 and water over the course of a few decades, and then the plants absorb the CO2 again.
As a consequence, as long as the number of rice plantations doesn't increase, the amount of methane in the atmosphere due to rice will stay largely constant. There will certainly be fluctuations because, as was mentioned:
> At best, growing rice and flooding fields might affect the balance between the amount of methane and amount of CO2 in the steady state,
but
> this is of no practical consequence, because the methane will not accumulate year over year, like the emissions from fossil fuels do
and the current total amount of methane in the atmosphere due to rice (which, again, is constant) – on its own – does not have devastating effects, as outlined by GP's hypothetical argument of doubling the amount of rice in the atmosphere. Put differently, reducing the amount of rice plants in the world would not provide any leverage against global warming.
The rice plants don't absorb or release methane, the breakdown of organic matter in the flooded ricefields causes the release of methane. In dry/unflooded fields, the decay would be much slower. The flooded fields possibly emit more methane and less CO2 than unflooded due to anaerobic conditions, but I'm just guessing.
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.
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.)
The point is, though, that the amount of methane that currently have in atmosphere, is only barely relevant when it comes to how it affects climate from human perspective. If all methane disappeared tomorrow, our climate would be back to 2010, which is hardy a significant change. Nobody would even notice other than climate scientists. Similarly, if we increase the rice cultivation, the amount of methane will increase in the steady state, but the increase will be wholly immaterial, so that it does not affect us in any real way. This is not really “bad”.
>our climate would be back to 2010, which is hardy a significant change.
Uh, no. It is quite significant, and a mountain of evidence says that the climate changes from concentrations in the last decade are very significant. You appear to be a denier of anthropogenic climate change who is willing to make silly straw men arguments.
I do happen to remember what the climate looked like in 2010, and I very much do not believe that enormous social and economic projects are warranted to revert the state of climate by 10 years.
> You appear to be a denier of anthropogenic climate change who is willing to make silly straw men arguments.
You appear to be unable to discuss the issue on merits, but this doesn’t necessitate resorting to ad hominem. You can do better than that.
> Actually describing the beliefs that you hold is not an ad hominem.
There is not a single thing I have said in this thread that can be interpreted as “denial of anthropogenic climate change”. You are welcome to find it and quote it though. On the other hand, there are many places where I very much reaffirm the reality of anthropogenic climate change, for example
Well, we can start with how you pretend that greenhouse gas concentration determines the current temperature, and not the rate of change of temperature. I bet you aren't stupid, so it's either willful ignorance or disingenuity.
Not the OP but: Sure, rice does cause some non-zero amount of CO2/methane in the atmosphere that would otherwise remain stored inside some other plants (or the soil) but, unless we increase rice plantations around the world, this amount will remain constant. Hence, it's a steady state.
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.
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.
Yes, this is exactly what I say in my comment. The amount of methane in the atmosphere is directly proportional to the input rate. That’s why, as I said, in steady state, when the we keep steady the amount of rice under cultivation, the amount of methane in atmosphere is not changing over time.
Can you point to which part exactly is “completely wrong”?
> Can you point to which part exactly is “completely wrong”?
First you said:
> Not really. These GHG emissions from rice are in steady state with the amount of CO2 and methane in the atmosphere.
And then now
> That’s why, as I said, in steady state, when the we keep steady the amount of rice under cultivation, the amount of methane in atmosphere is not changing over time.
These two statements are contradictory. If we assume steady state, then yeah the amount of methane is stable, but changing the way we cultivate rice is the opposite of steady state: if we reduce the methane emissions, then the amount of methane in the atmosphere will decrease that's it.
There is no contradiction between these two statements. They both say the exact same thing: if rice cultivation is in steady state, the amount of CO2 and CH4 in atmosphere due to it is constant. You next say if we change the steady state, the amount of methane in atmosphere will change, but that again is not a contradiction with what I said.
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 more reasonable in the near future than trying to harvest individual rice grains off of a perennial plant that cannot be damaged so that the plant can provide sun cover to prevent weeds... just not seeing it.
Also, Chinese harvests rice up to three times a year. And the harvest itself is much easier if you can grab entire plants. So I am not convinced anybody is going to get interested in it.
The assertion that a perennial plant "cannot be damaged" is also incorrect, many perennial crops benefit agronomically from a "trim", even non-perennials have economic circumstances where it makes sense to "damage" the crop, e.g. grazing winter crops in the late fall.
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.
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.)
This is also true in nature. Weeds (or think invasives in an ecological) tend to be plants that do best in disturbed contexts like fires, landslides, after logging, or in the agricultural sense, tilled soil. Invasives tend to struggle to gain a foothold in established healthy ecosystems
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 Yunnan, the province in which tests are being made, all such areas exist.
Many rice farms are small scale and on inaccessible land at the bottom of river valleys, terraced up hillsides, or otherwise inaccessible locations which would provide substantial scale-related and physical challenges to ease of automation. Try running an automated robot over this topography: https://upload.wikimedia.org/wikipedia/commons/7/70/Terrace_...
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.
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.
Are you talking about the machines that can mechanize the planting of rice seedlings? I find it hard to believe that poor farmers in China can afford these machines, unless this state is providing for free, or with zero interest loans and very long repayment periods.
Also, most rice farming in China isn't done on difficult topography. I call that stereotype the "National Geographic" effect. If you look where most rice farming is done, it isn't very steep or mountainous. See more here: https://www.statista.com/statistics/242360/production-of-ric...
China makes almost all of the world's EVs, the world's motors and the world's wheels. Putting together any kind of agricultural vehicle is cheaper in China than elsewhere. That's just how it is. How do I know this? I just returned from seven years making robots in China. I will stop short of looking them up and pricing them, but feel free to do so.
AFAIK the Agricultural Bank of China is the largest bank in the world by some measures. It almost certainly has the most branches, and these are overwhelmingly located in agricultural towns and villages. Recall also, in communism sharing equipment is normal. People don't all need to buy their own. Chinese villagers like villagers elsewhere help one another.
Yes, flat areas exist. But they are not the test area, Yunnan. And if you were to look at the historical spread of rice farming (a subject of considerable academic debate) you would notice that all academic suggestions of the earliest invention of rice agriculture itself, with very few exceptions, appear to disperse through or via the test area, because it is the natural headwaters of rivers feeding the majority of mainland East, Southeast and (very close by) South Asia, including the Yangtse, the Pearl River, the Red River, the Mekong, the Salween, the Irrawaddy, and the Brahmaputra. Given we know that in ancient times river valleys formed natural communications paths this give us a fair case for the general dispersion of rice farming technology specifically through steep terrain areas and specifically through the test area.
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.
What about the people practicing permaculture and regenerative agriculture? There's been a big movement there to perennialize crops, and there are well-known patterns and practices from there to work with perennials.
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.
Industrial farming of the sort you describe is destroying arable land, and relying on petrochemicals and strip mines to keep marginal land on life support. Properly managing the land using a mix of perennial crops and occasional rotation to pasture restores the soil, builds fertility, and requires very little in the way of inputs. Healthy plants in a polyculture setup where niches have been pre-filled also resist weed invasion better than monocultures.
We do a lot of stupid shit in farming for the sole reason that farm machinery is specialized, and proper land management costs more (in the short run, in the long run the land is much more productive).
> Depending on the accounting, they contribute as much to global warming as the aviation sector.
Methane's contribution to global warming is proportional to the rate of change on a window of ~20 years. Emitting methane doesn't warm the world. What warms the world is increasing its emission.
That focus on non-fossil fuel related methane emission is a huge piece of propaganda that people keep repeating. Most of those emissions were stable for decades. It's mostly fossil fuel related emissions that grew recently.
(But yeah, reducing the emissions will lead to a cooling of the world that can compensate some amount of CO2 emissions for a short term.)
That chart shows emissions per kilogram of food product. The absolute numbers are higher for rice because the world produces much more rice than coffee - about 10 million tons for coffee and 500 million tons for rice. That would put the absolute emissions from rice about 8 times higher than coffee (225 vs. 29 including methane emissions).
A relative who worked in the Philippine government on RICE specifically
His other quote was "we have this department because Rice needs to be on every plate, every meal"
The flooding isnt to prevent weeds, its to prevent INSECTS, and rice is very water tolerant.
---
So, wouldnt it be sane to say that perennial rice in a small growing area would be good.... also, have you ever seen rice drying on tarps on the side of the road?
So in addition to this you also need to account for how the rice is harvested and dried...
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 like we are lining up our miracles so by 2050, we’ll be at net zero.
Nothing you're saying here responds to the question. Everyone knows we're seeing climate issues.
Why does making agricultural improvements prevent dealing with coal?
> By not addressing the big problems sooner, we have shortened the window to seeing significant problems.
This is true of all problems, not just the big ones.
> We’d have more time to solve the smaller problems, or they may take of themselves.
If we dealt with all of the smaller problems, we'd have more time to solve the larger problems, or they make take care of themselves. For example, the population in China will drop significantly this century, reducing the need for power consumption from coal plants.
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.
As a devil's advocate (I too believe we can make simultaneous changes), what about the concept of "don't change more than one thing" during testing so you know exactly what change had what effect? What if we stop using coal and change agriculture only to find out that the effect was/is too much? To find out that the changes to agriculture caused side effects elsewhere. Mashing all the buttons at once rarely plays out as the correct method.
I could fill a book on the rationalizations about sequential prioritization just in the software industry. Our politics are chump change compared to geopolitical issues.
we've been proving since before the kyoto protocol that we really aren't capable of addressing much at once. the first clean air act was 60 years ago, while the paris agreement's net-zero horizon is 27 years out. i don't trust a many-pronged approach because i already live with the consequences of its failure
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 don't know why I should change my lifestyle while trucks like that still exist.
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 people conciously make awful lifestyle choices which will eventually contribute to their deaths. I don't know why I should change my lifestyle while people like that exist.
I have mixed feelings about this comment. It's good satire. But that's something I expect on reddit. Over here, it seems like we're running afoul of the forum norms, and Poe's Law.
That's fair. I meant it to be taken as an invitation to explain why (or why not) personal responsibility should matter in a world where the problems are complex and have a thousand sources. But I didn't do a good enough job of couching it that way, and it certainly pissed off the person I was replying to. I guess the responsible thing to do at this point is bail.
Depends on the action. Gluing oneself to the street in order to prevent 5% of 2% of an industry that is rapidly shifting to EVs is questionable, for example.
Heard about someone who glued themselves to rails before a coal plant. Allegedly that prevented the equivalent of 800 years of average western european lifestyle emissions. Here I'm trying to get my own climate warming impact to be at least close to zero (and failing), and this dude has a 10x impact by doing nothing but sitting on rail for a bit. The cost is losing 9 months of their life on jail time. (Definitely an interesting proposition were it not for (1) the likely reality that some other coal/gas plant just spun harder during that time, and (2) that I'd likely get more jail time because I did it knowingly and found it worth it and as such it's not a sufficient deterrent.)
I'm trying to rehab a 10th of an acre of prairie that used to be temperate rainforest.
That won't even offset my own impact on the rest of the world. But I'm showing up to meetings with other people, giving advice, hopefully some inspiration, as well as plants to make the process a little more accessible to other people.
Best case at the end of this, I've helped dozens of people reduce their carbon footprint, and they've helped hundreds do the same, and so on. All of us will still have a positive carbon footprint, but we've called into question what the average footprint should look like. Us and a hundred other people who think about things like transportation or building standards or entertainment.
The end goal is that becoming a giver instead of a taker represents sacrificing 10% of your lifestyle instead of 75%. It's very hard to peer pressure people into giving up 75% of what makes life worth living.
Is the idea that downstream consumers had an easier time retooling their processes to an entirely different power source than buying from a different coal plant? Questionable, at best.
Did the people working on rice hamper the work on coal? Or is the issue that they're wasting their time by doing anything but trying to get rid of coal? As best I can tell, neither you nor I are working on coal either.
+ while there are still people starving, this is helping to solve a big problem, it wasn't done for climate change, it's just nice that it might help there too.
I'll tell you the same thing I tell the average knob who spews "premature optimization is the root of all evil" at me as a way to get out of having to think about anything uncomfortable, or ever accept culpability for any problems:
You don't balance a budget by only looking at the tallest tent pole.
You have to ask yourself what proportion of the overall budget a particular concern is 'worth' and figure out how to get there. Until that total is reduced to < 100% you will always be in debt. Starbucks or no Starbucks.
From there you chip away at each element as the opportunity arises, balancing opportunity against cost (both of action and inaction). If something proves to be too hard to change, you have to compromise elsewhere. And in the long run, order only matters if you go bankrupt in the middle of the process.
I believe that flooding rice fields has a substantial positive impact on yields, and not just by combating weeds. Controlled flooding creates the perfect moisture + nutrient environment.
what about meat production? how does it compare to rice? This would be more relevant than comparing something completely avoidable (planes) with basic food
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.
Perennials are such an intuitively appealing idea but a plant expends a lot of energy ensuring it can make it through the fallow/winter season successfully. Thus perennial cereals only make sense where the cost of seed and planting exceeds the impact on yield. My understanding is even at the theoretical minimum energy needed for most cereals in most growing regions to have a 90% chance of surviving perennially you need a huge cash subsidy for lost grain yield or for seed and planting costs to rise many-fold. More likely to work in rice than wheat/kernza but never likely to work at all unless we as a species change how we think of the objectives of agriculture. Happy to be proven wrong though.
They explain in the interview that the rice is still sub tropical, so this only works in places without significant winters. With that the investment of the plant is likely much lower.
It’s hard to generalize but seed costs in the ballpark of 20% of revenue. That’s not counting tillage in preparation for planting, the cost of planting, or weed management which will be more difficult without established crops.
In other words you can take a significant hit to yields and still come out ahead.
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.
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.
I think that's why they used "fallow". Tropical climates do not have cold winters but may have dry seasons where, I would assume, a plant would enter a dormant state.
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 grab it all. And I think this is a deal breaker.
It just does not make sense to get even more labour intensive plant at a time where labour in all parts of the world that grow rice becomes suddenly so much more expensive.
So until they figure out to build robots that can individually pick rice grains off of a tiny, fragile rice plant, I am not seeing any future for perennial rice.
> 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.
Seems like it makes sense to them. The increased labor in harvest is probably offset by the decrease in labor for planting.
They may be. But consider that this is still early days. _Where_ these land are also matter. If they are on marginal lands that are difficult to cultivate, it makes a difference there. They specifically talked about smallholders rather than commercial agriculture. Although the absolute numbers it smallholders are small, it would be interesting to see what proportion of the smallholders have adopted this.
Note that, although I am commenting on the big thread started by someone claiming that it would help sequester carbon, I personally don’t consider that the main benefit.
I have some farming experience under my belt, zero with rice.
You have to look at labour as a function of season. If while planting, there are no competing jobs, but while harvesting, there are (or the other way around)... That would be your answer.
Whew, never thought I'd see TLI on HN....Work with those scientist on a different project. Interesting stuff. Acreage on Kernza has been slow to take off though.
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 perennial food plants. Like fruit trees and nut trees and whatever.
The benefits of perennials being, you don't need to plat then anew every year. And because the plants and especially their root systems are not killed off at the end of every summer, the soil is not vulnerable to erosion, because the plant roots stay in the soil and hold it together.
> 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?
The author is saying we should apply the techniques we've used on grains to fruit trees. That is ridiculous, because, obviously, we already do that. We always have.
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.
Not all rice needs to be grown in paddies. Paddies are primarily used for weed control as rice, as a water side plant, can tolerate root submersion where the competition can't. Some varieties do better than others as "dry land" rice. A perennial dry land rice would be a boon for small holders. A lawn could become a perennial food source.
I am currently working to adapt rice varieties to my temperate environment in a raised bed setting. Not having to use some of my harvested seed to replant would be awesome. The downside is you lose the ability to select for traits without ripping up your current plot.
Rice, like most grains, is a grass. Replace lawn grass with grain grass and plant fruit trees. Growing food isn't a one size fits all solution. Grow what you can with the least amount of effort.
Lawns as green space will last as long as food is plentiful. Changing a lawn to food production is the first step people will take if food is not available. The culture is already changing.
There are a surprising number of perennial food plants. Not just bushes and trees; vegetable crops too! I recently saw a Gardeners' World episode which showcased a lady with 220+ perennial vegetables in her garden. Including a variety of broccoli, and one of chard! A surprise to me.
A benefit to her is, she could have all that without dealing with every plant, every year. But she had plenty of rain and land. Not everybody would find that solution beneficial.
Certain crops we grow annually will perennialuse just fine in the right environment. We bought a perennial kale last year only to have it completely die, meanwhile a kale I didn’t pull at the end of the fall is shooting new leaves.
Right plant, right place. We’re still working on it, thousands of years later.
Well-designed food forests and agroforestry systems can exceed the calorie production per acre of heavily mechanized and fertilized annual crops like corn, while providing tons more actual nutrition and additional services like wood, good quality soil, etc. with little or no fossil-fuel-based inputs. Check out i.e. Mark Shepard (New Forest Farm) and Martin Crawford (Agroforestry Research Trust) for examples.
They have little incentive since non-financial externalities are not accounted for in commercial agriculture. In other words, we aren’t accounting for the costs of topsoil and ecosystem destruction, or greenhouse gases from fertilizer and pesticide production.
Industrial agriculture has increased yield mostly via unsustainable external inputs: fertilizer, pesticides, and motorized machines (oil, oil, and more oil).
> So what our colleague Duyan Tao did - he, at an early stage, around 10 days after the [by-human-hand] pollination, went in there and dissected out the very young embryo that was developing and put it in tissue culture and gave it nutrients to help it grow. And then he rescued one of these seedlings. And that was the beginning of it.
Also, the "old-fashioned genetic engineering" of selective breeding of animals/plants is...not as old-fashioned as you may think. Animal husbandry has been around for millennia (or longer), but it was an undirected process prior to the work of Robert Bakewell in the 1700s. Thanks to his groundbreaking work (and a lot of refinements from others), humanity learned how to shape the trajectories of other species. I like this quote from Bakewell's wikipedia page[0]:
> In 1700, the average weight of a bull sold for slaughter was 370 pounds (168 kg). By 1786, that weight had more than doubled to 840 pounds (381 kg).
(Obviously, humanity has gone on to be much more aggressive and successful with selective breeding. Beef cattle are now usually 1200-1400 pounds at slaughter, for example. Though, personally, I'd say we've gone "too far" when you learn about the horrors of modern, industrialized animal agriculture.)
Ehh it's getting into pedantic territory as to what counts as directed vs undirected, but people figured out pretty quick that if you have an animal with a desirable trait you can breed it with others to maybe get offspring that also have that trait.
As an illustrative example, consider the fancy pigeon (see [0] for some pics). One of Darwin's original areas of study was to prove that these birds, many of which have cool-looking but incredibly maladaptive traits, were actually the same species as the pigeons you'd see on a London street. Prior to that, the scientific consensus was that these were fully distinct species -- i.e. the artificial selection happened so long ago that it was lost to time. Given some breeds have trouble even eating (e.g. look at the beak on this guy [1]), I think it's a pretty safe assumption that this breeding did not happen without careful human intervention.
That's not to say that the kind/degree of artificial selection we see in industrial agriculture isn't worlds away from older forms. Once you've got the basics of evolution and the scale of capitalist production, you're starting down the road to the current world of 100 pound antibiotic-riddled chickens in rows of 10000 cages. But humans have been selectively breeding animals for food, utility, or just because we kinda felt like it since time immemorial.
That's a very good point. I'm currently suspecting that the numbers quoted in Blakewell's article are the "hot carcass" weight (i.e. subtracting bone, head, and organs from the total weight). An Aurochs (wild ancestor of domesticated cattle) could reach 1300 lbs in the 1500s (and possibly in excess of 3300 lbs prior to recorded history, according to archaeological finds)[0].
If the numbers are hot-carcass weight, we would be seeing:
1700: 370 lbs, 1789: 840 lbs, 2020: 880 lbs [1]
But, uhh, that doesn't feel right either. I think that wikipedia page could use some additional citations, but I'm struggling to find useful numbers with which to update.
Domestic animals in the Middle Ages were definitely smaller than today, you can see it in illustrations that depict agricultural work.
For people who lived in swampy areas (e.g. north of England), having lighter animals with longer legs was actually preferrable. Meat-and-fat balls of today would get stuck and drown in mires.
My wife is from Thailand. My father in law is a rice farmer.
I’m unclear about the definition of “subsistence”, because you need more than rice to live, but he grows more than they need to eat and sells the rest to eke out a living.
The questions in my mind are:
1. How expensive would these perennial rice strains be (patents)? The cost would have to be ridiculously low by western standards for rural Thai farmers to afford this.
2. How sustainable is it from the standpoint of soil nutrients? Would farmers have to fertilize since they usually plow under after harvest and let the field lie fallow for 6 months? Fertilizer would likely be a show stopper.
> 1. How expensive would these perennial rice strains be (patents)? The cost would have to be ridiculously low by western standards for rural Thai farmers to afford this.
Near as I can tell, they do not patent their crops for revenue. According to https://landinstitute.org/learn/frequently-asked-questions/, they do have one of their grains trademarked and extract fees from those who use the trademark. Which strikes me as a fair play but others opinions may differ.
You can plant the rice along with nitrogen fixers. Perennial plants get old and should be replanted periodically, so you can have a fallow period where the land is grazed to really improve fertility.
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?
As I understand it the result of monoculture soil damage is not in detectable nutrition of the crop but less yield due to reduced hardiness, slower growing, susceptibility to pests & pathogens.
I know very little about rice cultivation but the flooded fields system has very different cycles and feedback from dry land grain cultivation. It varies a lot by region but rice paddies are entire ecosystems, with specific fish & eels introduced to control pests and enrich the fields. At least for the first few years iirc rice cultivation itself actually somewhat terraforms the land, improving it for rice cultivation. I'm sure there are drawbacks, caveats, and limits on that but I don't know what they are. I suspect you'd need to be a dedicated rice crop expert to have a truly informed understanding of it.
Perennial plants are much more effective at extracting nutrients because of more established root systems. Not tilling the field also allows for complex plant/fungi communities to develop which will increase moisture and nutrient levels in the soil. Put simply: you don’t need to fertilize a forest or other naturally occurring ecosystems and those are built around perennial plants. The closer you get back to a functioning ecosystem, the less resist you’ll be on external inputs.
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.
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
I found these walking onions a couple years ago planted a bunch of them along a hugelkulture berm that I constructed from downed tree trunks, decomposed wood chips, grass cuttings, compost and topsoil. They are definitely planted in the absolute worst spot right at the base of the berm instead of on it where the best nutrients should be. In spite of that I have seen them thrive in the poor soil. They do indeed form small onions at the tips of the stalks and those do tip over and root forming new plants. The whole thing is edible from the tiny onions at the top to the onion at the root. They also taste great so they have that going for them. If they can grow in the Texas heat with someone like myself tending them whenever he thinks about it then I think they will survive anywhere. I fully expected all of them to burn up in the heat but they have done quite well.
How will it affect the top soil nutrients? I used to be told about crop rotation and resting by farmers in south Asian countries for the soil to regain the nutrients, doesn't having rice grow year after year destroy the top soil and result in poor productivity?
Here in Argentina I think we plant in the same spot soy and corn, or soy and sunflower, or other combinations. Each crop is better for the temperatures and rain of each season. So I also guess it's more effective to use a annual crop (that is actually only a few months in the field, not the whole year).
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.
Perennial plants are much more effective at extracting nutrients because of more established root systems. Not tilling the field also allows for complex plant/fungi communities to develop which will increase moisture and nutrient levels in the soil. Put simply: you don’t need to fertilize a forest or other naturally occurring ecosystems and those are built around perennial plants. The closer you get back to a functioning ecosystem, the less reliant you’ll be on external inputs.
Some of the wild corn (maize) relatives are also perennial, for example Zea diploperennis. I wonder if there are efforts to also create perennial corn. I'm not sure how advantageous perennial corn would really be because of increased pest and disease problems.
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 soil degrades. This flooding is mostly used to control for weeds, but weeds have a much more difficult time competing when a perennial canopy already exists.
So, perennial rice may end up reduce GHG emissions substantially.