This is relevant as Anya Fernald talks about carbon-capture in soil and tending to soil as multi-generational farmers once did. https://www.youtube.com/watch?v=ew8U43IXTfk&ab_channel=LexFridman
Yes sort of… on the one hand the OP article mostly debunks the idea that significant amounts of carbon can be stored in the soil, but on the other hand there are natural and partially man-made examples of soils containing a lot of carbon (Chernozem grass steppe soils and bio-char supplemented soils in the amazon).
So my take-away is basically that we have to be very careful with the carbon stored in the soil. Higher temperatures might very well release a lot of it, and a longer drought might completely turn over the delicate balance of soil organisms and micro-aerobic clay layers and start a run-away soil-carbon loss.
So yeah, careful tending of soils and shaded permaculture etc. might in theory work, but scaling that up will be very difficult, especially now that there are few people left working in agriculture, so most is mechanized.
Carbon-capture in soil was a completely new concept to me so I was surprised to see this post days after having heard that podcast. I suspect you’re right that it’s a fragile process with a lot of details but I take it as a sign that extreme weather events becoming more common are leading more people to recognized the climate change problem. Maybe hearing how hard people are working to put carbon in soil will cause others to make better choices about their own carbon/energy use.
Ah, I assumed you were aware of it beforehand as it has been talked about for quite some time and is even included in some climate simulations.
The main issue raised in the OP article is actually not so much about artificially storing carbon in the soil, but rather challenging the assumption many non-soil scientists (based on outdated soil-science) have made that once the carbon is in the soil it will not be released again very quickly. The old reasoning was that “humic” substances would persists in the environment and not easily be digested by soil organisms.
As someone trained in this general field but not having worked in in for more than a decade this was indeed news (and very bad news) for me. This means that similar to the methane & carbon stored in the permafrost, so is the carbon stored in the soil of places like the Amazon going to be released quickly if the conditions turn unfavorably for the current ecosystem there. Basically we are looking at yet another positive feedback loop with potential to make an significant impact on atmospheric carbon levels.
But in hindsight this is actually not all that surprising as the Sahara desert used to be a lush green grassland and forest as little as 10,000 years ago, and it certainly did not retain much carbon from that time in its sand dunes today.
That in addition plans to artificially store carbon in the soil (a dream long held by bio-char proponents) are likely unrealistic is overall less relevant :(
A good article. Two things that they touch on but don’t emphasized that I think are the absolutely critical take-aways
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Soil isn’t the same everywhere and we miss opportunities when we generalize them. They are as different in process, make up, and biota as the other parts of tundra and jungle.
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Soils are balanced, interacting systems (ecosystems). Carbon cycling is impacted by nitrogen cycling; the N Cycle is impacted by biota; biota is impacted by hydrology. We can take all of those statements and reverse the order and they’re still true. We can replace x and y in ‘x in soil is impacted by y’ with nearly any components of soil have it still be true. These are very complex systems.
Bottom line, thinking we can get any random soil to hold on to carbon just by putting some there is about as wise as expecting a toddler not to spill an open cup of juice you hand them. That isn’t saying that a targeted approach can’t be effective.
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