Study about the nutritional impacts of removing animals from agriculture

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brimstoneSalad
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Re: Study about the nutritional impacts of removing animals from agriculture

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Canastenard wrote: Tue Nov 21, 2017 5:33 pm ... and now I feel like this topic has become my Wiki page's equivalent of the "Nutrients of Concern in progress" topic in this section rather than what is originally was about (a specific study).
That's alright. There will probably be a few references to that study debunking the claims it makes in the article. It's all pretty relevant. :)
At least for countries like the U.S. and some others that highly subsidize animal agriculture, it will probably be important to look at those and the cost claims.
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Re: Study about the nutritional impacts of removing animals from agriculture

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Canastenard wrote: Wed Nov 15, 2017 4:21 am I can't access the full study
The full study is now available here:http://www.pnas.org/content/early/2017/11/15/1707322114.full

I made a video after reading the full study. I really tried to be open minded, but the assumptions they make are just ridiculous. For example, they raise concerns about increased obesity, because plant based agriculture will produce 23% more calories. Apparently they have a pretty poor understanding of economics if they can't figure out what to do with excess food. It apparently dawned on them eventually, though, and they mention that "consideration of specific nutrient needs and international nutrient/food routing is essential to determine the balance of agriculture needed to feed the global population."

In other words, it might make sense to trade extra food we don't need, for food we do.

The study also assumes absolutely no supplement use whatsoever. So it's not that Americans wouldn't be able to get enough vitamin D and B12 supplements - they just don't bother assuming that's even possible.

And they list arachidonic acid as one of the 9 nutrients that may be hard to get on a vegan diet. These nine vitamins/minerals/fatty acids are seemingly chosen at random, and a few of them betray either a complete ignorance of nutrition on the authors' part, or a deliberate attempt to mislead. Arachidonic acid is synthesized from linoleic acid in all mammals aside from obligate carnivores. Their proposed diet (which contains plenty of foods high in linoleic acid, like canola and soybean oil) would provide more arachidonic acid than any person needs, but they list it as zero in their scenarios. Again, they're either ignorant of the metabolic pathways for linoleic acid conversion, or they just want to confuse people. Ditto EPA and DHA - vegan diets may be LOW in these fatty acids (which is a concern), but the number is not zero, and by making it look that way they could seriously confuse people.
Canastenard wrote: Wed Nov 15, 2017 4:21 amI also wonder what they did about sessile animals like oysters that are likely non-sentient;
No, they did not.

They don't even bother restructuring current crop growing patterns (they basically say they did this to keep things simple). Their model assumes that just because we have more land, we'll be growing more cucumbers (even though people are already eating plenty of cucumber and its a low nutrient food - why not use the land to grow better things?). The assumptions of the study are remarkably simplistic. A high school student with a calculator could have constructed the same study. Seriously disappointing, given the resources that White and Hall have at their disposal.
Edit: there's a detail I missed first when reading the abstract, they mention: "When nutritional adequacy was evaluated by using least-cost diets produced from foods available, more nutrient deficiencies, a greater excess of energy, and a need to consume a greater amount of food solids were encountered in plants-only diets"
[/quote]
Bizarrely, the authors were extremely concerned about adding "bulk" to the diet. I'm not kidding. They felt like an animal based diet was more efficient, because the calories are more condensed. "Within each food availability scenario, plants-only diets required 444–522 g more food solids than those with animal products to meet nutrient requirements." Oh my. I'm sure eating a couple of cups more food per day (and a lot more fiber!) would be terrible for Americans!

I really hope more people will read the paper and either write blog posts or make videos debunking it! (I'm looking forward to hopefully seeing some videos from Mic the Vegan and Unnatural Vegan in particular). I honestly wanted it to be a good study, but it's just not. It's disingenuous (the whole "if we grow 23% more calories than we consume, Americans will become obese!" Line of argument was a major tip-off that the authors weren't even attempting to avoid being biased).
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Re: Study about the nutritional impacts of removing animals from agriculture

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Well, that's finally a study that fails miserably at debunking the sustainability of a nationwide vegan agriculture. Good think the cognitive dissonance I temporarily felt for promoting a diet that would be nutritionally unsustainable for everyone was for nothing after all :lol:

For the Wiki article (link for easy access: http://philosophicalvegan.com/wiki/index.php/Sustainable_Vegan_Agriculture) I added informations in the Crop rotation section, explaining the environmental disadvantages of long-term monocropping and the importance of alternating crops. I also added a sub-section about cover crops, which is about restoring soil health with plants grown for their beneficial effects rather than for direct food production. The Wikipedia article did a good job at explaining it: https://en.wikipedia.org/wiki/Cover_crop

And the FAO website also has infos on cover crops: http://www.fao.org/ag/ca/2a.html

Next I'll probably add infos about uses for agricultural waste such as straw. I will mention its uses as a source of biofuel, and the uses of distillers grain byproducts as fertilizer and nitrogen source for composting.
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Re: Study about the nutritional impacts of removing animals from agriculture

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ModVegan wrote: Wed Nov 22, 2017 10:32 am The full study is now available here:http://www.pnas.org/content/early/2017/11/15/1707322114.full

I made a video after reading the full study. I really tried to be open minded, but the assumptions they make are just ridiculous.
Wow, great post, and thanks for clearing up the claims in the study. I'll read the whole thing when I get a chance.

This was a good summary.
Could you post here, to let us copy some of your comments into wiki articles?
http://philosophicalvegan.com/viewtopic.php?f=5&t=3335
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Re: Study about the nutritional impacts of removing animals from agriculture

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Before I start to write about use of agricultural waste I did some more research about straw fermentation and ethanol byproduct fertilization. Here are some relevant links:

A link about research for the most suitable yeast for ethanol production from straw: https://www.uea.ac.uk/about/-/agricultural-waste-could-be-used-as-biofuel
A study about the environmental sustainability of wheat straw as a source of biofuel: http://www.sciencedirect.com/science/article/pii/S1364032113005716
Another study that's optimistic about ethanol byproducts as fertilizer: http://cdn.intechopen.com/pdfs/20070/InTech-Fertilizer_potential_of_biofuel_byproducts.pdf

I'm linking the second study because it raises concerns about removing straw from agricultural lands rather than letting it decompose in the soil where it was harvested:
[...] However, there is an ongoing debate regarding the potential effects caused by the removal of agricultural residues.

Except for a few literature reports [19,20], the effects caused by wheat straw removal for bioethanol production purposes are neglected in most bioethanol LCA studies. Removal of wheat straw rather than ploughing back to the field may raise several concerns: (1) decreasing the soil quality which leads to additional synthetic fertiliser applied to balance the nutrients removed with the straw, (2) increasing field emissions due to applying additional fertiliser, and (3) decreasing soil organic carbon stock which leads to a loss of carbon as CO2 to atmosphere. These effects caused by wheat straw removal on ethanol life cycles and comparison results with petrol are discussed thoroughly in this study.
To be fair the idea of letting straw decompose in the soil it comes from didn't cross my mind. I was under the impression it wasn't a good idea because I thought its high carbon to nitrogen ratio would make it a poor soil amendment.

And a question about byproducts: after research it seems like DDGS really has good potential as a fertilizer. However I wonder if ethanol production from straw would also provide a nitrogen rich byproduct that would be for all intents and purposes equivalent to DDGS. Intuitively I see no reason why not, but maybe I'm missing some key differences that would make distilled straw byproduct less usable than distilled grains, and the fact the study in the second link I provided made no mention of byproducts of straw distillation makes me a bit worried. Because either the study is right and using straw as yeast feedstock would make it unavailable or unusable as soil fertilizer, of they forgot to take distillation byproducts that actually can be used for soil fertilization into account in which case the study is flawed.
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Re: Study about the nutritional impacts of removing animals from agriculture

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I believe the majority of the nitrogen in either case is incorporated into the cells of the yeast, so I wouldn't expect it to be substantially different when adjusted for ethanol production. If we could find data on that, that would be great though.
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Re: Study about the nutritional impacts of removing animals from agriculture

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brimstoneSalad wrote: Thu Nov 23, 2017 6:00 pm I believe the majority of the nitrogen in either case is incorporated into the cells of the yeast, so I wouldn't expect it to be substantially different when adjusted for ethanol production. If we could find data on that, that would be great though.
I tried to search for that. So I typed "straw bioethanol company" on Google and found this website: http://www.sbe.fi/SBEeng/Factory.html
I was surprised to see no mention of DDGS equivalent as side product so I sent them an email to confirm. I have yet to get a response as of now.
But then I saw they mentioned a website named inbicon.com so I visited it: http://www.inbicon.com/en
It has a page that mentions the end products of straw distillation: http://www.inbicon.com/en/key-advantages/end-products
So I guess I got my response in advance: the DDGS equivalent is apparently molasses with 5% protein content in dry mass (assuming that's what "DM" means). It's suggested as food for livestock, but also for further fermentation. The lower protein content makes it seem like it would be worse that DDGS as a fertilizer due to higher C:N ratio. Maybe it could be used as feedstock for nutritional yeast? That would mean much less recyclable nitrogen that what I expected, but that's maybe not necessarily a bad thing if that nitrogen ends up directly as human food rather than passing through plants multiple times before we eat it (and possibly return it to the soil if we're using biosolids), as processing agricultural waste that way would increase the amount of edible food without increasing artificial fertilizer use.

Although it expressed concerns related to increased uses in synthetic fertilizer, the second study I linked in my post above still tends to believe that biofuel from agricultural waste would still overall be a win if that biofuel can replace the same amount of petroleum, assuming we're using the right way to get ethanol from straw.

I'm also wondering about nutrient extraction from the ocean, since due to gravity elements necessary for life end up in it. We do mining for things like phosphorus, and even though we probably have a lot in reserve, it might be good to think about extracting essential plant nutrients from sea water. Could seaweed cultivation be a way to do it? Although it is edible, we wouldn't eat directly much of it because it is so rich in iodine and an excess can be dangerous for health, which would mean the rest could be used as fertilizer (or maybe we could process it to remove iodine to safe levels to increase the amount of seaweed that could be directly be eaten by people). It has a high nitrogen content (a C:N ratio of 22:1 in a compost with 82% seaweed and the rest being fiber byproduct of sugarcane processing: https://www.researchgate.net/publication/275524578_Seaweed_compost_for_agricultural_crop_production) which means it could be effective as a fertilizer if we want to use it as such. However I'm not sure if cultivated seaweed alone could sustainably compensate to give us the phosporus and potassium and other plant nutrients that are inevitably leaking from a nutrient cycle even with biosolids and composted food waste (we should also make sure most of our food waste gets composted rather than rotting in a landfill and releasing methane in the atmosphere). For now it's probably not a huge concern with mined phosphorus, but when reserves are going to run out (maybe not in our lifetimes, but during that of our descendants if humanity is still around in the next centuries) we might need to find a way to harvest it sustainably.
Here's another page that discusses seaweed as fertilizer: https://www.rhs.org.uk/advice/profile?pid=301
To be fair I'm intuitively not convincing myself that seaweed farming alone could sustain all our needs for phosphorus and potassium, unless maybe we put seaweed farms literally everywhere on coasts but I don't think we would want that. So we also might use other techniques, but they might be more costly in energy, but it looks like it's not impossible as this study suggests: http://www.sciencedirect.com/science/article/pii/000326709280134S
The total dissolved phosphorus is extracted efficiently by adsorbing it on to iron(III) hydroxide surfaces [iron(III) hydroxide-coated acrylic fiber], following a technique used earlrier for the extraction of dissolved silicon and other trace elements from sea water.
Another topic I want to address is crop rotation. I already described it in the Wiki page, but it looks like there's more nuance than that. Not that it's not beneficial, but it's apparently often impractical, a major reason for monoculture being disparate demand for different crops, plus the fact different climates and environments are most beneficial to different crops. Although not a primary source, it was being suggested by this page: https://skeptoid.com/episodes/4454
[...] If there was an equal demand for corn, soy, and cotton, farmers would be able to rotate perfectly and everything would be hunky dory.

Sadly that's not the case. In 2011, the United States had 84 million acres of corn; 74 million acres of soybeans, 56 million acres of hay, 46 million acres of wheat, but only 10 million acres of cotton. So many products, both food and industrial, come from these, but the acreage needed from each is so disparate that crop rotation is often problematic. Further complicating it is that each crop grows best in a specific climate zone and soil. It's really, really hard to find two or more crops that are both in equal demand and that will grow well on any given farm's ecology.
Seeing the references it looks like it was most likely taken from this link: http://www.epa.gov/oecaagct/ag101/cropmajor.html however visiting it redirects me to https://www.epa.gov/agriculture which means the link is dead. So I searched on Web Archives and found an archived version: https://web.archive.org/web/20130521220052/http://www.epa.gov/oecaagct/ag101/cropmajor.html
The numbers on the page are correct, but I see no mention of "there is monoculture because demand of all of it is not equal" on this EPA source. It sounds like an educated guess from the one who wrote the blog page, how accurate is that? And because demand for all these things would be different in (and, in the case of crops grown for livestock, probably considerably lower) how would convenience of crop rotation translate in a vegan country? Maybe it would mean a lower overall demand for soy and corn (since they're common livestock feed) making it more on par with wheat, and thus making crop rotation easier or more effective thanks to more similar demand?
Or maybe we might want to develop region-specific varieties for staples like soy and wheat, that grow better in specific regions and climates so different ecology in different zones is less of a constraint for effective crop rotation. I wonder if genetic engineering could be of any help in accomplishing that goal - in which case it would debunk a common anti-GM argument "they genetically standardize all our crops and thus recude biodiversity" :P
And by the way, I could also add an advantage of crop rotation I didn't mention before - it works as pest management by breaking the life cycle of pests that attack specific crops over others.

Finally I'm glad I did start a Wiki page on sustainable vegan agriculture, because I don't know everything it means I must do my research and that's pretty fun and I learn a lot.
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Re: Study about the nutritional impacts of removing animals from agriculture

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You're doing a great job!

Seaweed is a great source of nutrients, both for human diet and fertilizer, but production is rather expensive for use as fertilizer. We'd have to look into the economics; maybe you can find some examinations of the costs there?

We should probably model a sample diet, looking at limits in terms of purines and iodine from SCP and seaweed.

Peak phosphorus is not a big concern. Much of the Earth's crust is rich in phosphorus and other relevant minerals (like potassium), at worst we're just running out of easily accessible reserves of highly concentrated rock that's easy to process and ship, the price will increase slightly. Of course, I don't think animal agriculture is helpful to mitigate this; trees may be. It doesn't seem like a big deal though.
we should also make sure most of our food waste gets composted rather than rotting in a landfill and releasing methane in the atmosphere
That will be easier when there's no meat in the waste stream, since it opens up vermiculture options.
A very nearly closed cycle for minerals should not be impossible, since they don't have anywhere to go except in the garbage and down the drain (aside from a small amount of dust lost).
Not that it's not beneficial, but it's apparently often impractical, a major reason for monoculture being disparate demand for different crops, plus the fact different climates and environments are most beneficial to different crops.
Demand for grains will decrease and demand for legumes will increase substantially in a vegan world (we will be growing much less corn, except for biofuel/plastics), and we will need less overall land so we can probably choose to farm in areas where both of these crops grow well.
Green manure may be easier in some cases, though.

Also: don't forget hemp. It's very efficient in terms of protein per acre, and hempseeds and protein should become much more popular. The plant can also be retted for fibers, although I'm not sure if the same cultivars are good for fiber and food.
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Re: Study about the nutritional impacts of removing animals from agriculture

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Sorry I've been taking a break in this recently. But now I feel like discussing this again.

I know we really need to recycle nutrients from the waste stream if we want to make the nutrient cicle as closed as possible, but it seems like there are concerns about safety, in particular pathogens and toxic chemicals. While pathogens are inevitable and thus need proper treatment to be destroyed (long time composting and heating), I feel like we could reduce concentration of heavy metals and certain other toxic chemicals in waste-based fertilizers by separating waste treatment from toilets and the rest, which would mean that excrements would not be contamined by industrial waste. Of course this assumes that a considerable majority of the matter that can act as plant nutrition indeed comes from the toilets and we're not losing a significant amount by not exploiting the rest, and also that there are management benefits in separating toilet waste from the rest. And it would also have to be an improvement to the point it would overcome the huge amount of work to put on an already established waste treatment system.
Trying to do research about this I also saw mentions of prions, which are a class of highly resistant hazardous proteins. However, it seems like prions from sludge mainly comes from waste of animal carcass treatment plants such as slaughterhouses, which would obviously be much less of a problem in a vegan world, and wouldn't be a problem anyway if we separated toilet waste from industrial waste.

Still about biosolids, I found an interesting article on the subject: https://www.hindawi.com/journals/aess/2012/201462/
In addition to sanity concerns, are mentioned odors and nutrient runoff. As a way to minimize odors they mention "directly covering or incorporating biosolids into the soil", and by "incorporating" I suppose they mean mechanical action on the soil, in other words tilling, which is not good for soil microfauna. They also mention to avoid applying them in windy times, which sounds like it may work but would be impractical for farmers since it would have an impact on the planning of their activity. Maybe not much of a big deal if it's something like occasionally delaying application by one or two day, but maybe it could also screw over their long-term plannings.
For nutrient runoff it isn't a huge surprise considering livestock manure also has potential for eutrophication, with the source of the problem in this case being high phosphorus content. I guess it would have to be managed similar to synthetic fertilizers.

Another article, this time less optimistic: https://cen.acs.org/articles/89/web/2011/06/Safety-Rules-Sewage-Sludge-Outdated.html
It shows that a class of pathogens, noroviruses, are more resistant to classical sludge treatment. They may not be as bad as other pathogens, but their presence in food is still not something we'd want to accept. However the article is more than 6-year old, maybe recommendations have changed since that.

I also searched about seaweed fertilizers, but that research was from last week before I took a break from this topic and I don't remember everything. I'll try to research more in the next day. But for what I remember the problem with seaweed is that is doesn't seem to have much in nitrogen and phosphorus by weight, which would mean it wouldn't be a sufficient way to provide these nutrients. Its strenghts are instead the hormone-like chemicals it has that promote plant growth and its good mineral content.

I would also like to see concerns about phosphorus and potassium better addressed. The problem is not finding sources of them, it's about finding concentrated sources of them. For now we can get them from high quality mined rocks, but later we'll have to get it from less concentrated sources; even if we never get to see that in our lifespans, it may be relevant to future generations, so we might talk about phosphorus and potassium extraction technologies from dilluted sources like sea water.

(And for the mail I sent earlier, no response. Which is probably not relevant since I already got my answers by researching more.)
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Re: Study about the nutritional impacts of removing animals from agriculture

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Most pathogens aren't an issue except for in vegetables that may be eaten raw. Things that beans and grains that will be processed and cooked before being eaten may not be a problem.

Sewage could also probably be used to fertilize fields growing plants for green manure or ethanol.

The big concern would be the heavy metals; as you said, I think we'd need to know where these were coming from. Industrial waste might be part of the issue, but very likely a lot of it is from plumbing. We probably have a good reason to get lead out of out plumbing anyway, but on the waste side the questions of infrastructure investment may be pretty significant.

Thanks for researching this! :D
This should be a great article.

By the way, ModVegan posted in the permissions thread, so we can add her comments on the paper if you want to add a section on that.
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