Watch: Before the Flood
Posted on 3 November 2016 by Guest Author
Join Leonardo DiCaprio as he explores the topic of climate change, and discovers what must be done today to prevent catastrophic disruption of life on our planet.
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My wife and I watched the film together. Afterwards we were musing on the corporations, politicians and media that are complicit in the campaign to sabotage climate action. Her comment was that these guys don't have their heads in the sand, they have their heads in the tar sands! Hmm, I wonder if there's a cartoon in that!
Just finished this up last night. The weather station in Greenland is possibly the most disturbing.
It reminded me of when my parents and I vacationed in the Northwest and we visited Glacier National Park. At the time (I don't know if they still do this 20 years later) they had a series of signs that posted were the glacier extent ended. So of course, the signs just kept going back farther and farther. I don't think I appreciated at the time that the glacier was disappearing; I probably thought it would come back eventually (within my lifetime), but that clearly was my young ignorance.
Mired in desperation, while buoyed by tears of joy in the hope in the heroic efforts and achievements, this video is a delicious way to welcome one more day in which contribute my little bit to help, especially as my 3 year-old worked herself into my lap to watch the saving of, or destruction of her world. Thanks for finding this, and for all the effort SkSc contributors make toward this critical comunal effort; this is what all the statistics and arguments offered in SkSc really mean.
I actually like the movie. However, as expected the "backlash" from getting agricultural science wrong is in fact happening as I predicted. It is much like the backlash on energy fueling denialism. (pardon the pun) So to try and counter in some small way this nuance, I compiled a mock interview will many of the agricultural "giants" that are influencing using regenerative agriculture as a biological carbon capture and sequestration (BCCS) mitigation strategy. Most these viewers are not farmers or scientists, and quoting scientific studies or facts seems to fall on deaf ears. But hopefully this may have an effect. It seems to have in at least some cases.
So yeah we need those animals on the farm.
But why are they a problem?
So that is the problem? The feedlots and the vast acres of monoculture corn and soy supplying them. Why are those bad?
Oh I get it, pesticides!
But I heard pesticides are safe, why would killing a few weeds and grasses and insects fungi etc. be a problem? Who cares about a few bugs, and worms?
What about weeds?
OK I get it. We define whether something is a pest or not. In a different context a pest could be beneficial, as flowers are food for bees and pretty too. But wouldn't it be expensive? I like organic foods but the price at the market seems a bit higher.
So would changing the way we do agriculture help?
Solution? That's pretty strong words. Even as big a problem as climate change? How can that be?
The soil? Really?
Wait! That's philosophy! I mean in practical terms!
What's so special about the soil besides the worms Darwin talked about?
What good things?
OK, I think I am starting to see how these are connected. Less pesticide inputs and the important creatures survive and can do their job! What would that radical change look like? How is agriculture done differently? Is it just the cow? Or can this work for other animal species?
That's interesting, the pigness of the pig! So how would we figure out the pigness, cowness, chickeness, or even the tomatoness and wheatness or any other of our agricultural foods?
I think I get it now! It took the greatest minds in the history of sustainable agriculture. But now I understand what to look for when grocery shopping! Thanks so much everyone!
There is more carbon missing from the soil than extra in the atmosphere.
So forget about the guilt trip. If the meat and vegetables you eat are raised properly on land that is increasing in organic carbon, you'll actually be helping mitigate climate change with every bite!
RedBaron @4
That's an interesting way of putting it. However, for someone like me who is ignorant of agricultural practices, it might be more enlightening to read a description of future practices as changed to be indefinitely sustainable and how these differ from current practices.
This reminds me of systems engineering. I worked with systems engineers for part of my career and I learnt a little about the discipline in the process. Regarding the above, two systems-engineering lessons seem to apply:
The first lesson is that one has to have a clear vision of what it is one is attempting to build, or in this case, establish — hence my first point above. As my erstwhile colleagues put it, "If you don't know where you're going, any road will get you there." So describe how the farmers of the future in the various branches of agriculture go about their business. How does this differ from today? One can't get from A to B if you don't know what B is.
The second lesson concerns technology. Whatever one sets out to build, one should only rely on currently available technology. To get from the A of current practice to the B of future practice, one cannot assume use of a technology that has not been shown to work. But I should imagine one would have to exclude any technology that relies on the burning of fossil fuel.
Perhaps what I ask has already been done. If so, I've not seen it in any of the generally available news sources. If not, well, that would be an interesting project for someone with the relevant expertise, would it not?!
I dont want to knock good farming practises and advantages to climate from that but I am still skeptical about claims being made. Are you aware of these Powlson paper RedBaron?
"Soil carbon sequestration to mitigate climate change: A critical re-examination to identify the true and the false"
and
"Limited potential of no-till agriculture for climate
change mitigation"
Both suggest the advantages are being oversold. Perhaps we need some food labelling to indicate whether the farm source is managing to increase SOC?
@Scaddenp,
Not only am I familiar with both those studies, I happen to agree with them. In fact I was stating that very thing long before the studies came out! As I have stated elsewhere here at this forum, that's why we have two sets of numbers, with very different calculated ranges of mitigation potential. Those two sets of numbers corresponding to the potential for industrial ag to mitigate AGW, and the potential for regenerative ag to mitigate AGW. There are fundamental differences that are profound with regards to ecosystem function.
Industrial ag is based on a net sum zero production model. Regenerative ag is not bound by this, as it is a complex biological model. Just to give an example pertinent to the movie. Methane. In the industrialised production model we have now we can improve methane emissions by careful manure handling and collecting methane as a biogas fuel. But at the absolute MAX the best we could even even theorectically do is collect 100% of the methane cows emit. Grass fed beef in a properly managed MIRG system has the potential to offset 100% of all cow emissions plus a substantial % of emissions from other sources due to increased biological oxidation of methanotrophs in the soil that grow and maintain themselves at concentrations lower than atmospheric. That's just one example to iilustrate the point.
In realistic terms that means the best we could ever hope for without fundamental changes in the production models would top out around 18-20%. Although some unrealistically optomistic studies top it out at nearly 60%. I have doubts it could ever reach that high. Maybe.
But change the production models and we get very different numbers starting at 62% min and going all the way up to 250%+. BCCS is just a completely different approach that doesn't function in the same way as the systems those links you posted function.
Can you point me to a paper showing net SOC from MIRG operating on a podzol that wasnt degraded by cropping before the trial started? Podzols are what we have and no one here can point to any SOC increase from any dairy operation except short term gains on degraded soils.
@Digby Scorgie,
Agreed with pretty much everything you said! We do have to have a clear vision, and it must use technology available right now! You are absolutely correct. Since you are unfamiliar, let me give you double sets of examples, first to show you what it can look like, and gradually ease into a more scientific analysis.
Lets start with Beef (although it applies equally for all large grazing herbivores)
How to green the world's deserts and reverse climate change | Allan Savory
Restoring The Climate Through Capture and Storage of Soil Carbon ... White Paper
Grazing management impacts on vegetation, soil biota and soil chemical, physical and hydrological properties in tall grass prairie
Next lets add wheat and most small grains. Here is what it looks like and analysis of case studies.
Why pasture cropping is such a Big Deal
Liquid carbon pathway unrecognised
Carbon That Counts
Next rice
India's Rice revolution
The System of Rice Intensification (SRI)… … is climate-smart rice production
JOURNAL ARTICLES ABOUT THE SYSTEM OF RICE INTENSIFICATION (SRI)
And even though probably the most significant gain is in NOT growing so much corn, (at least 50-70% less) there still is a need for SOME corn. So to do that requires a kind of integrated hybrid system between the modern industrial and regenerative models.
Gabe Brown: Keys To Building a Healthy Soil
Innovative No-Till: Using Multi-Species Cover Crops to Improve Soil Health
I actually could go on and on for every little crop, but hopefully you have a clear picture of the principles in your mind now, and can see the pathway forward. There are actually a few minor gaps still, but nothing substantial enough to limit the potential of this mitigation strategy. Like the movie correctly stated, things like vegetables are about 1% or so. The big ones covering the majority of land are covered with the posts above.
@8 scaddenp,
I think that would be an almost impossible task, since podzols are primarily forest soils. So right off the bat, just being in grass shows it most likely was degraded already when the forest was removed. BCCS would basically use that as pasture only until the topsoil recovered, then reforest it if possible.
Now for years it was thought impossible to ever convert a podzol into a mollic soil. I did hear a soil scientist in a lecture claim almost as an aside that this is no longer the case. But he didn't provide a case study or published paper, so I have no way to pass that along to you.
RedBaron @9
Cor blimey, mate! You've given me a lot of homework! I'm going to be off the air for quite a few days while I digest this!
Red Baron:
Out of curiousity, are you familiar with the work of the International Center for Biosaline Agriculture (ICBA)?
Thank you RedBaron. That goes a long way to explaining the dissonance between what is published and talked about here, and what you claim for US agriculture. Podzols are all we have.
Like Digby, I have got a lot of reading to do just from the reference list of the Savory paper you linked to. Now, how about an approach to dairying that isnt treating the soil as a hydroponic medium while pouring nitrates into river and groundwater...
@13 scaddenp
Now that request is much much easier! Not only can you eliminate nitrogen fertilizers in a dairy system, your yields can even go up! Like before I will start with the easy to understand video to let you see the concept, then another like to a dairy manual and case study info at the USDA.
Trantham's Sustainable 12 Aprils Dairy Grazing Program: A Top Farm that Almost Went Under
12 Aprils Grazing Dairy Manual
And there is a different method used that also yields more per acre, but a bit less per cow by pure MIRG that doesn't need nitrogen fertilizers. Useful if you don't have a no-till planter useable for planting into sod.
Pastures for Profit: A guide to rotational grazing.
What a lot of those guys do is raise something else to make up for the increase in forage while the yields per cow slightly drop. Something like sheep or beef. Or in some cases instead they let some go back for a season for wildlife, similar to this:
Grassland birds: Fostering habitat using rotational grazing
One thing for certain though. I am quite confident the issue as to why the dairymen in your area are failing to continue to sequester carbon is the nitrogen they are using. There is absolutely no need for nitrogen ever in a dairy operation. It actually is counter productive as Tom found out only after he was forced to stop using it due to bankruptcy. Same thing Gabe found out too with his beef and corn operation. Same thing I am finding out with my vegetable research.
There is also one more option available for you if you are willing to expand beyond just dairy. You could try pastured eggs. Now this guy raises beef, but some of his graduated intern students use the exact same system, but with dairy and laying hens combined:
Meet the farmer: Polyface Farm
Intensive RG has been backbone farm practise here since 1950s (Gallagher electric fence invented here in late 1930s with massive improvement by the Phillips fence in early 1960s), but latterly, world milk prices have given rise to dairy conversion from both crop and lowland sheep, using large-scale irrigation systems on what was dryland agriculture with lots of nitrate as well as RG. We manage very high productivity per ha with low costs (eg see comparison of US with NZ done by Wisconsin here) with these systems. Since yield per ha seems to be driving force, it is going to be hard to get better soil management established, except that this dairying does increase SOC significantly on places that used to be dryland cropping, but not elsewhere. Intensification on traditional dairy areas by adding more fertilizer is also bad for SOC.
@12 John,
Nope I am not familiar with them. I did a quick skim. Seems pretty legit to me. I don't see any red flags.
Red Baron @4, claims that:
That claim, however, is inconsistent with actual records of changes in CO2 concentration, as, for example, those documented in the Global Carbon Budget 2015:
As can be seen, combined fossil fuel and cement manufacture contributions(189 ppmv equivalent) exceed the combined increase in ocean Dissolved Inorganic Carbon (DIC) and atmospheric CO2 (182 ppmv equivalent). The land use contribution, including that from plant matter and Soil Organic Carbon is less than the reduction due to reforestation in the northen hemisphere and the greenhouse fertilization effect. Extending the data back to 1850 shows cumulative land use change emissions to be just 68% of the increase in atmospheric CO2, with industrial emissions representing 174% of the atmospheric increase.
Further, measurements of C13 in sponges show there to have been no large influx of carbon into the atmosphere or ocean since 1350, other than that coincident with the rise of industrial emissions:
To clarrify what you are seeing, the atmospheric pCO2 show measurements from icecores and and mauna loa. The Jamaica, Shallow Water show measurements from sponges at a depth of approximately 25 meters, which being in the mixed layer are expected to track atmospheric levels fairly closely. Those from Pedro Bank (approximate depth of 125 meters) are below the mixed layer, and so should track ocean levels of DIC. None show a large perturbation prior to 1850, after which records of fossil fuel use show them conclusively to have been the largest contributor to the increase in atmospheric CO2.
In short, Red Baron's claim is simply inconsistent with what is known about the carbon cycle in recent times.
@15 Scaddenp
You said, "Intensification on traditional dairy areas by adding more fertilizer is also bad for SOC."
Exactly my point. There is intensification due to management changes using biomimicry as a model, and intensification with increased inputs of fertilizers. The first should theoretically be able to push through the SOC barrier you describe. The second never can and never will. Goes back to what I was describing above in post #7 where we have two sets of numbers. But to actually give you a case study to prove that? Not sure we have a case study on your type of podzol on the books as of yet, since although common where you are located, it is rare overall, as this is a relatively rare forest soil to find in dairy operations elsewhere in the world. I personally would contact Dr. Christine Jones from Australia, to see if she might know of one.
I know the strategy I would try. I could even set up a side by side case study by splitting your dairy farm into two and try one beside the other. Or even 3. But I simply don't have access to a case study good or bad under the narrowly defined criteria you require. I don't even know that this particular strategy of intensification has even been tried. As far as I know, only extensive and high input intensive have been trialed side by side. Do you have a case study where low input intensive was case studied but failed to work?
@17 Tom,
I think maybe you read that wrong Tom. I am not claiming that all the soil carbon lost can be found in the atmosphere. It has gone many places, mostly wind and water erosion...and some into the atmosphere as well. The point is to address saturation, not to deny the major influence of fossil fuel emissions. Even though BCCS in the soil doesn't have the same saturation level as industrial ag or biomass sequestration in forests. There would have to be some finite saturation point somewhere. We know that point has to be at least as high or higher than soils' SOC were prior to degradation due to agriculture. So taking those figures we know that before we fill up the soil sink "bucket", we will run out of extra CO2 in the atmosphere "bucket". So far the soil sink is still large enough. But if we keep burning fossil fuels at these ridiculously high rates, eventually even as large as the soil sink, it would no longer be large enough.
Ps Addition to post #18
That should read,
"Do you have a case study where low input intensive was case studied but failed to work?"
I have case studies of low input intensive (and heavily managed grassland) that have been shown to "work" (maintain SOC), but not at the stocking intensities common in dairying here. It seems that in US land values are lower and stocking rates much lower and more emphasis on output per animal. SOC is regularly monitored all over the country in numerous farm management systems. However, increasing SOC is not a priority. Would only become one if it was somehow involved in increasing net$$ per ha beyond what is achieved with high input. With more protection being ordered for groundwater and rivers, that may happen, but present government will not act in way that would reduce farm incomes, particularly when milk prices relatively depressed.
@21 scaddenp,
We are getting about 5X the stocking density using MIRG, than set stock rates. ie 400 cow days per acre in areas that typically get 80 cow days per acre. That's over 2 cows per hectare, almost 3. If you add chickens you get even more cow days plus eggs too. (chickens greatly improve pasture by eating parasites, grasshoppers and spreading manure) They are the clean up squad that follows a few days after the cows are off to another paddock. All this without a drop of nitrogen or irrigation and 30" annual rain.
RedBaron @19, I did not assume you meant that all SOC lost had gone into the atmosphere, but it must have gone somewhere. The industrial emissions in CO2 concentratin equivalent since 1870 accounts for 100% of atmospheric increase plus 100% of ocean increase plus 9% of the land sink. Given that, to a first approximation, Land Use Change emmissions, only part of which is SOC, cannot exceed 93% of the Land Sink (or 63% of the atmospheric increase). Given that much of the LUC comes from deforestation, the SOC loss accounts for appreciably less than that.
Strictly speaking, the Land Sink, Ocean DIC, and atmospheric CO2 are not the only sinks; and nor are anthropogenic sources the only sources. Allowing for these extra factors as per AR5 Fig 6.1, we can allow for 30 GtC being sequestered as ocean floor sediments and/or buried organic matter (ie, the raw material of future fossil fuels), but that is nowhere sufficient to make up the shortfall. Nor is the 3 GtC of Marine Biota (which is more likely to have declined than increased). The only other reservoir available is dissolved organic carbon, which the IPCC has as unchanged since the preindustrial, but which you require to have increased by 50% over that period for your claim to be true. Well, either that, or allow violations of conservation of mass.
Further, a large influx of dissolved organic carbon (of the order of 100 GtC over 150 years or less) would result in a large increase in DIC, with both showing as a significant change in δ13C; which has been shown to not have occurred by the sponge data. Given this, and absent any paper showing a large increase in dissolved organic carbon, your claim is shown to be false.
Redbaron, our average was 2.9 cow/ha in 2013 with 1060 kg/ha of milk solids, much of it on podzols. I dont see anything in your resources that doesnt sound like common practise here - except that now they get stocking increase with inputs as well. Irrigators are taking dairy into areas with 18-25" rain pa.
Scaddenp,
Right then basically the same yields per acre but with no inputs and better soil carbon sequestration.
Tom,
Sorry but not sure what you are missing, Of the ~2,700 Gt of C stored in soils worldwide, ~1550 GtC is organic, which is approximately double the current atmospheric C which is ~780 GtC.
This in not counting soil carbon held in peat and wetlands (150 GtC), inorganic C in soils (950GtC) and in plant litter at the soil surface (50 GtC).
~1550 GtC is the current levels but 1/2 of the topsoil on the planet has been lost in the last 150 years. So the size of the sink would be at least ~1550 GtC or greater before we need to worry about saturation, with all the carbon in the atmosphere only ~780 GtC and all we need to remove? What? Maybe 150-200 GtC. So the sink is approximately 10 times larger than it needs to be.
So at this point the main factor is rate of flux out of the atmosphere and into the soil. i am guessing maybe 40 years or so. However, emissions would thwart that time frame, melting cathrates could too. And I am no expert but I am told the ocean which is now a sink would turn into an emissions source should we start drawing down atmospheric carbon.
So maybe we will need all of that spare sink capacity?
Ultimately my statement was not false. We are missing 10 times more carbon from our soils as there is extra in the atmosphere.
RedBaron
Your numbers don't seem to add up. If carbon lost from the soils is 10 times what we see in the atmosphere, given that known human emissions from fossil fuels are only about 1/2 of what we can see in the atmosphere, that means that 10.5 times the visible extra in the atmosphere has gone somewhere else. 150 years isn't long enough for significant transport to the deep ocean so where could all that carbon be?
No way the ocean could have taken up that much carbon and not be noticed. Gas exchange balance with the atmosphere would mean that concentrations in the atmosphere should be significantly higher. Or if it was organic carbon in the oceans, it would be visible. The graph Tom highlighted doesn't suggest anything like that level. And there is a balance between dissolved organic carbon in the ocean and marine biota. More DOC would produce huge blooms that metabolise a lot of it, converting it to inorganic carbon, entering the carbonate system and being detectable.
Your argument seems to violate mass balance.
What I would question, though I don't know the details, is the claim of 50% loss of topsoil in the last 150 years. Is that 50% of area or volume? Loss of top soil is certainly an issue - an oft quoted figure is 1/3rd of farmland is losing soil faster than it is created. But 50% already lost? Sounds too high. That would suggest that a reasonable proportion of the planet is back to bedrock.
Do you have a source for that number?
Read up on it.
Pimentel et al. 1995. "Environmental and economic costs of soil erosion and conservation benefits." Science 267: 1117-1123
The numbers are 20 years old. It's even worse now.
RedBaron @25 and 27, by talking about the potential size of the Soil Organic Carbon (SOC) reservoir as a sink for carbon emissions, you have changed the topic. Your evidence for the existence of a reservoir of that size is the purported loss of SOC to that extent due to agricultural practises, but in that event SOC loss represents have cumulative emissions approximately 4 times those from all other anthropogenic emissions. Worse, it means you need to find an additional 1550 GtC in known surface carbon reservoirs, ie, more than twice the size of the Dissiolved Organic Carbon reserervoir. Apparently over (at least) 800 GtC, having left the soils has "softly and silently vanished away" without going into any reserservoir.
Asked to defend these figures you point to a peer reviewed article which only claims a 50% topsoil loss for Iowa, not globally. That article further asserts that "per capita food supply has been reduced over that last 10 years [ie, 1985-1994] and continues to fall", whereas modern data shows the opposite:
It also claims that arable land is being lost at a rapid rate, but if so it is being gained at an even faster rate, for total arable land increased at a rate of 2 million hectares per annum from 1961-2013, while total agricultural land has increased at a rate of 10.6 million hectares per annum (FAO data). Further, the article does not directly discuss loss of SOC, and while its claimed 75 billion tonnes per annum of top soil lost from agricultural lands represents a problem, that loss is mostly from the 10.5% of the land area under cultivation. Most of that top soil would be deposited as silt in flood plains, or over land (if wind blown) so it does not represent the global loss of soil, still less that of SOC. In short, the paper does not appear to be reliable, and is certainly not directed to the point of discussion; on top of which you overstate its claims.
Tom,
If my soils tests out at 8% soc and I lose it so that later my soil tests out at 4% SOC as I gradually destroy the topsoil or lose it to erosion. That is still arable gound. In fact with heavy fertilizer use I can probably still farm for a whileIn arable ground statistics you won't see it lost, only degraded. Further if I plow a former grassland or forest, (which starts the degradation process) it will actually show in statistics as arable ground increasing. This explains the apparent paradox you are seeing. Nor do I claim that the carbon vanished completely, some entered the atmosphering pool, some entered the ocean pool, some is redeposited only floodplains like the famous Nile Delta, etc... but sediments in rivers lakes and the ocean are a very large part.
However, the soil that has degraded down to as much as 1-2% SOC due to agriculture (basically farming on subsoil) can be managed in a different way to start increasing SOC. Is it too much of a stretch for you to believe that it might be capable of reaching that % SOC found historically? After all the subsoil is roughly the same parent material in roughly the same locations. It reached those higher SOC levels at one time. Why would you think it impossible to do it again with an agricultural system using biomimicry?
RedBaron @9
I had an initial look at all the links you provided and then a closer look at those to do with grasslands. The following is what I deduce to be the recommended method of livestock management on the relevant grasslands in the future. I have no idea if I have summarized this correctly. My background is physics, not biology, but this is the sort of description I was looking for. I would appreciate having my misperceptions corrected.
Farming in a zero-carbon world — grasslands
On grasslands subject to alternating wet and dry seasons, livestock are managed according to a holistic grazing plan. This type of plan specifies when and how long animals will be in any given area. The animals are herded in tight groups and confined to relatively small paddocks by means of fences (either temporary electric or permanent) or herding or both. The technique amounts to multi-paddock mob-grazing. The aim is for the animals to have an intense but brief impact on the land — anything from several hours to a few days. The animals eat the grasses, forbs and shrubs available — the more diverse the better.
The farmers carefully observe the plants that are eaten for signs of over-grazing and adjust accordingly the amount of time the animals are confined in any given paddock. The grazing plan is therefore not fixed but evolves continuously as the farmers monitor the impact the animals are having and the rate of recovery of the plants in the other paddocks. Over-grazing is avoided.
When and where necessary, land is rested by the complete removal of the animals. The purpose is to allow bitten plants and their roots to recover and regrow after proper grazing and animal impact. Over-resting land is avoided as much as over-grazing, however, as this also leads to degradation of grassland. The rest period may be anywhere from a month to two years, depending on various factors. This period of rest is an essential part of the process, which always includes the return of intense short-term grazing and animal impact pressure after the recovery period.
(The above summary is heavily based on the work of A Savory.)
One can add more, explaining how the above method mimics Nature (before humans screwed things up), listing the advantages (particularly from a climate-change point of view), comparing this method with typical current practice, and describing how one initiates the process of restoring already-degraded grasslands using animals.
Should I go on, RedBaron, or should I leave it to the experts?
Digby,
That's a pretty good summation of HPG in a brittle environment yes. Keeping in mind this was the type of grassland that always befuddled any attemps to restore it. Certain other less brittle grasslands are much easier to restore and more forgiving of poor management, but do also show improvement using HPG.
RedBaron
I'm encouraged. I'll go on to the next aspect, but as usual it'll take me a few days.
Digby,
One thing to consider as well is birds. Several farmers, most famously Joel Salatin, have figured out how to follow the grazers with birds. Usually chickens, but sometimes turkeys geese etc.... Generally if chickens, this is approximately 3 days later. The chickens primarily eat bugs, grasshoppers/locusts and fly larvae in the cow patties. This "clean up crew" produces a very high quality egg or meat product with extremely high nutritional values far exceeding hen house chickens, on at least 20%+ less grain. And actually by spreading the herbivore manure, eating pests, and adding their own high nitrogen manure, improves the grasslands even more. This also means the cows don't need wormer, as the chickens break the life cycle of herbivore paracites too. And for the farmer, another stream of income from the same acreage. Often farmers add bees too, with their obvious benefits. Also some people are planting certain nut and fruit trees intermixed loosly and managing it like an open savanna.
When you start adding multiple species of herbivore, and symbiotic species like chickens, turkeys, swine, bees etc. to a HPG management system and vertically stack all these symbiotic production models on top of each other, the total yields per acre start shooting through the roof. Profits too. And surprisingly, the soil building properties also increase dramatically as well. It becomes, counter-intuitively, the more you take from the land, the more it produces.
RedBaron
I'll bear what you say in mind — but this is hard work for someone with a physics background!