I've wondered if it's a good/awful idea to use the widely used food irradiation tech [1] on manure to kill the microorganisms that can cause disease, while keeping the bioavailable nutrients intact, just like how radiation kills bacteria in food without affecting its taste.
It's also very low energy as, unlike electro-shocking, the radiation sources are "always on".
Feces ... is microorganisms, mostly bacteria. It is mostly correct to say poo is made up of bacteria. Lots of kinds, lots of species. Soil is likewise alive.
If you kill everything you take a competitive ecosystem of many species and leave raw materials for the next, most invasive colonizer which is often more likely to cause disease.
Sterilizing manure is likewise pointless unless kept in a sealed container, once you expose it to the world it's going to get something alive in it real quick.
To prevent disease you really need to do the opposite, let it ferment longer to allow the various waves of decomposers access to break down and metabolize as much as possible to get the resulting material further away from what it would be like inside a living body as the more different environments are, the less likely species will be able to thrive in both environments. (this is why fermenting pickles works, microbes that find salty veggies tasty won't find you tasty because you're not nearly so salty or acidic)
You do sterilize manure as mushroom culture to prevent competition with the fungi, but that is done in quite controlled environments.
It's a bad idea in general, because a healthy sustainable soil is more than just available nutrients. Good soils also have micro-organisms that break down organic matter which also releases more nutrients, introduces air into soil, some even have symbiotic relationship with plant roots.
Also, you don't put raw manure directly into soils. You need to compost them first for at least 6 months. That alone breaks down and kills harmful organisms.
there are many more beneficial bacteria in the environment than disease causing ones. wiping them all out may decrease some disease incidence but prob cause more issues like allergy/eczema etc.
For non-subsistence farming, the amount of manure needed to replace the amount of nutrients being removed every year can result in too much of some things which can harm the ground. Growers have to be careful not to accidentally salt their ground with manure.
Manure is also very heavy, and therefore expensive to transport, and that’s without going into restrictions that kick in when moving animal waste long distances.
Pathogens, weeds and even pesticide residue are also a concern. The dairy I work with makes use of large digester tanks that help reduce these.
Basically manure is great when you are close to a source (like a dairy), but you can’t put on too much or move it around too far without issues. So there is value in being able to economically break it up into it’s components.
"Although manure itself can be used as fertilizer, doing so can be costly, logistically challenging and has environmental drawbacks."
... but knowing what I know about permaculture design, this assertion comes from a particular way of seeing, one that that contributes to system issues. It's not enough to look at efficiency, you also have to look at efficacy. I think the simple aproach of muck-spreading is better.
Integrating ranching with farming reduces the "logistical challenge", and proper design means the "environmental drawbacks" turns into solutions.
You don't have to be a permaculture gardener to have skepticism about highly processed artificial inputs to biological systems. Fungal and insect biome that break down and live within decaying organic matter represent hundreds of millions of years of development. Ancient Taoist philosophy is centered on the wisdom of aligning with natural process. IMHO modern science is learning, but still knows so little about natural systems, particularly relationships within insect, fungi and angiosperm communities which are the objective core of botanical systems. We live in exciting times, but the future of agriculture is certainly not DDT, trucking in guano from Pacific Islands, and John Deere harvesting machines.
I hear a lot of push-back and skepticism here about uncontextualized ideas coming from permaculture design, and I have learned to make it clear about the frame, paradigm, and worldview I am speaking from. A common push-back is about efficiency and scale and confusing it for efficacy.
Going along further down this road, what's a bit of a mind twister is when I assert it's better to approach Kuberenetes like gardening. A lot of the apparent complexity are actually part of the self-healing mechanisms.
As far as Taoist philosophy goes, not everyone buys into that, and there are multiple ways to interpret and approach Taoism. Still, have you ever read a book entitled, "Treatise on Efficacy"?
Hey, I just want to thank you for the book recommendation. Reading the preface to "A Treatise on Efficacy: Between Western and Chinese Thinking"[1] it seems to codify a lot that I've previously thought about.
And as a topical aside, I can personally vouch for the practicality of humanure[2] and ph-adjusted urine-capture[3]. They are indeed simpler, scalable, and well within that sweetspot of minimal inputs and maximal outputs, particularly when it comes to fertility.
This one is a bit more tangential (but still related to decomposition by ecological systems), but I think really cool. Have you ever checked out Dr John Todd’s work on ecomachines? (The guy who found a method to break down DDT in 40 days and had worked on a superfund site that had the EPA top 10 pollutants).
Given that most farmers already use chemical fertilizer rather than shit, we're not short on data for analysis.
One benefit you overlooked is knowing exactly what and how much you're putting in your soil. A bag of ammonium nitrate gives you a known quantity to factor with while shit is far from homogeneous in its makeup.
This is promising if they can scale it economically for the farmer. Here in Michigan there are some large dairy farms producing electricity from their manure. But the only reason they can do it profitably is because the cost of the installation was subsidized by both the government and the manufacturer.
When I was an agronomist I worked with several large dairy's in West Michigan on composting their manure. It eliminated most of the odor and had the additional advantage of greatly reducing the volume so they could use an ordinary fertilizer spreader and transport it to fields that could actually benefit from the nutrients. That was 25 years ago and they're still doing it so I guess they found it beneficial.
It's also very low energy as, unlike electro-shocking, the radiation sources are "always on".
[1] https://www.cdc.gov/foodsafety/communication/food-irradiatio...