On the surface it looks just like a fine sand but unlike sand there must be something about the micro-structure of this material that holds much more water than expected.
Pore space for water holding and cation exchange.
palagonitic dust, which contains hydrated and hydroxylated volcanic glass of basaltic composition, accommodates significantly more H2O under comparable humidity and temperature conditions than do the smectites nontronite and montmorillonite.
What’s in Palagonite?
How is it formed?
Does it make a good soil amendment?
Overview of Palagonite for Organic Farming
Personally, when used as a soil amendment, I’d prefer something with lower levels of Aluminium Oxide and Titanium Dioxide, Sodium Oxide is borderline too, but you can’t argue with the results when mixed with compost.
Composting with Palagonite:
During it’s formation gasses become trapped.
This 3-D rendering, produced using X-ray microtomography at Berkeley Lab’s Advanced Light Source, shows a cube-shaped sample of pumice (blue-gray) and pockets of trapped gases (other colors). The X-ray studies helped scientists uncover how gas becomes trapped by surrounding liquid, causing pumice to float on the ocean’s surface for prolonged periods.
Credit: Berkeley Lab, UC Berkeley
Oxygen comprises one fifth of our atmosphere, and we take for granted that this a good thing. After all, aerobic creatures like ourselves could not exist without free O2. Not all life shares this feeling. Oxygen and its derivatives (known as “reactive oxygen species” or ROS) can wreak havoc on the biochemistry of many microbes. For some obligate anaerobes such as methane-producing archaea, even a small trace of oxygen poisons them irreversibly (see, for example Kiener and Leisinger 1983). Others fall somewhere in the middle. Microaerophiles (e.g. Helicobacter pylori, the cause of gastric ulcers) require small amounts of oxygen but are unable to tolerate full atmospheric concentrations (Bury-Moné et al., 2006).
Why are these organisms sensitive to oxygen?
Have you ever noticed how when you mow regularly you get more pioneer weeds appearing with a strong taproot? Do you have poor heavy clay or stony soil that your back doesn’t fancy digging much? Are you just starting out and don’t yet have enough compost to no dig like the experts? And are you searching for a more holeistic approach to your gardening?
Why do all the hard work yourself when you can be like the weeds!
Well now you can with this one weird stick!
But that’s not all! Call now and we’ll include this set of augers for those whose soils are like concrete.
And, if you’re one of the first 100 callers we’ll include 200 buckets to hold your compost for only 50c extra!*
*each, shipping and handling not included, may come with extra frosting.
A new study titled Is the rate of mineralization of soil organic carbon under microbiological control? suggests that:
- the rate limiting step in SOC mineralization is abiotic (physical rather than biological).
- that mineralization of SOC may be a two-stage process: firstly, non-bioavailable forms are converted abiologically to bioavailable forms, which, only then, undergo a second process, biological mineralization.
I’ll speculate and say that mineralization is perhaps limited by dissolved organic carbon in the form of plant exudates, and humates with complex and random chemical structures that are produced by weathering and detritivores that consume plant litter. Liquid compounds that tend to be lost when composting.
Compounds that are probably why wet climates and seagrasses sequester the most carbon.
Why drying and wetting of these compounds leads to CO2-Bursts.
Compounds we should be trying to keep in the soil profile doing good, and not in aquifers or waterways creating algal blooms, like we really need to with this recently discovered underground molten lake the size of Mexico!
That depending on the complexity of the carbon molecule as it gets passed down the soil carbon continuum food web it may be more than a two-stage process, with more than one in both the physical and biological realms based upon chemical energy and chemisorption of the carbon compounds.
*shrugs* Just my guess, I suck at chemistry.
Add 1.5% biochar to a 3.5% (0-100mm sampled) soil organic carbon soil, wait 9 years and it begins to positively prime. Clearly they didn’t add enough to reach a tipping point faster, or depending on your perspective and availability, adding biochar to low carbon soils is a long-term investment. I assume it was surface applied as the study is paywalled.
Paywalled: Biochar built soil carbon over a decade by stabilizing rhizodeposits : Nature Climate Change : Nature Research
Nutrient cycling may suffer even when those soil microbiomes grown in high phosphorus soil are then later used to inoculate other soils.
Laura Kaminsky: Phosphorus and the soil microbiome of alfalfa
Curtis argues for small scale mini monocultures for productive urban farming, do you buy the argument? I call these intensive farming and market-driven monocultures because they’re all about consumerism and the ease of harvest and driving produce to market efficiently, yet at potentially some expense to environmental sustainability and diversity depending on the inputs and outputs.
An expense that appears inevitable in modern society, yet how do we quantify that? How many urban farming plots like Curtis’ could a local ecosystem tolerate before diversity suffered or does it actually increase diversity? Where is the balance? Are these it? Can these systems be made even more environmentally friendly while still maintaining the productivity? He certainly sounds like he’s tried.
If you look at Zaytuna Farm you also see these mini monocultures with diverse row cropping. Are these kinds of systems the best we can come up with for intensive farming?
Same applies to Richard Perkins, planting six varieties meeting more market demand for lettuce mixes.
It makes me wonder what a diversity audit in an urban farming setting might look like.
Are these farmers making a Zone 1 argument and that makes it acceptable in an urban farming environment because it’s close to where the produce will be consumed and can be tended to with little resources like Curtis’ bicycle?
Still, a part of me likens these kinds prosumer arguments to that of Lyle Landly from The Simpsons, with Lisa and Marge questioning the motive.
Is the real answer Barts; “Sorry environmentalists, the mob has spoken?”
When the microbes aren’t doing the work because they’re not being watered, housed and fed well, some farmers do that work for them.
In the video from India they explain how they use dried topsoil and subsoil for fertigating their crops via foliar spray. This has multiple effects, the first is providing soluble and insoluble nutrients to the plant surfaces for plants, microbes and sunlight to break them down, and second is adding to existing topsoil where more active microbes may utilise them.
However care should be taken as many clays from subsoils are known to have antibiotic effects, even on superbugs, and the application of foliar sprays with these clays has been shown to eliminate some plant pests and diseases. Many subsoils also have low pH that make kill some microbes.
So on one hand applying subsoil may be supplying nutrients and could increase productivity, and this appears to be the case in India. On the other and depending on the soil it could initially be killing the plant and soil microbes that produce them. This can potentially break the natural cycle and make this a system that requires continuous human intervention.
In the video they recommend 3:1 dried topsoil to dried subsoil in their foliar spray, with that increasing in subsoil content to 1:3 for disease eradication.
Every 10 days or even weekly…
They are effectively mining the soil to liquid feed the plants for continuous cropping.
Whether this is sustainable or even regenerative is a good question.
Does this practice build soil over time? Could it? Is that building as much as they excavate and does it compensate for the energy used to distribute those nutrients? They do mention increased plant nutrients, but I’m not sure if they also tested the soils.
On one hand the drying of soils is effectively hunting and killing microbes and their mucilages for their nutrients, on the other you get increased productivity. It’s like robbing Peter to pay Paul, which is the best investment? The same applies to killing off plant predators with foliar spraying, effectively feeding the plants with dead microbes and dead soil.
But perhaps this produces more plant exudates that produce more symbiotic root microbes to kickstart nutrient cycling above the level in the root zone needed to build soil rather than consume it?
If done in combination with diverse cover cropping and chop and drop to provide a cover and food for the soil I can see it being a useful tool to help get back to letting nature do the work, instead of the farmer.I think of this in the same way as I think of tillage. Initial minimal tillage can kickstart a system faster towards a regenerative approach by decompacting soils and releasing nutrients for plants to establish and grow and photosynthesise thereby feeding more microbes that build soil and reduce soil density.
It’s important to keep in mind too that tilling kills off fungi and earthworms, and so using any technique that disturbs soil should be minimised.In situations when access to organic matter is limited I can see these approaches helping get an initial crop in the ground to then be regeneratively managed. On the other hand where there is plenty of organic matter and soil moisture a no dig approach may be more appropriate.
The ocean sequesters massive amounts of carbon in the form of “dissolved organic matter,” and new research explains how an ancient group of cells in the dark ocean wrings the last bit of energy from carbon molecules resistant to breakdown.
A look at genomes from SAR202 bacterioplankton found oxidative enzymes and other important families of enzymes that indicate SAR202 may facilitate the last stages of breakdown before the dissolved oxygen matter, or DOM, reaches a “refractory” state that fends off further decomposition.
Zach Landry, an OSU graduate student and first author of the study, named SAR202 “Monstromaria” from the Latin term for “sea monster.”
Study illuminates fate of marine carbon in last steps toward sequestration| Oregon State University
For the first time, researchers have shown that cultured picocyanobacteria, Synechococcus and Prochlorococcus, found in the open ocean release fluorescent components that closely match these typical fluorescent signals found in oceanic environments.
“Two genus of picocyanobacteria – Synechococus and Prochlorocccos – are the most abundant carbon fixers in the ocean.” said Chen. His lab maintains a collection of marine cyanobacteria and cyanoviruses. Some of these isolates were used in this study.
“When you sail on the blue ocean, a lot of picocyanbacteria are working there,” said Gonsior.” They turn carbon dioxide into organic carbon and are likely responsible for some of the deep ocean color coming from organic matter.”