If it were only temporary the deforestation over the last 5000 years or so would have increased the amount of grassland and increased the amount of sequestered CO2. The exact opposite has happened, changing forests to grasslands and resulted in a massive reduction in sequestered CO2 over 1000+ year time scales. Conversely periods of reforestation have sequestered CO2.
Not true at all. The soil carbon pool is much larger than all the atmospheric and biomass carbon combined. Even in their highly degraded states due to poor agricultural practices, soils still contain much more carbon. If you study the soils, you find that the soil carbon is concentrated under what was historically grasslands and/or savanna/open woodland. This has been well established by soil scientists for over 100 years.
Mollic epipedon What they didn't know was causation to explain the correlation. It was a mystery because it is very counter-intuitive how a smaller decomposing biomass could account for vastly more soil carbon.
Cenozoic Expansion of Grasslands and Climatic Cooling
So what changed this time?
Farming Claims Almost Half Earth's Land, New Maps Show
New maps show food production now takes up 40 percent of the Earth's land surface, revealing the extent to which farming has changed the face of the planet, scientists say.
It is agriculture that has changed this dynamic. Now when a forest gets removed, it often is prevented from regrowing by the plow and/or herbicides. Furthermore, vast areas of grasslands are also plowed and/or sprayed with herbicide.
The natural succession along with the ecosystem function of soil creation and carbon sequestration has been destroyed by these practices. So you lose both biomass and soil carbon and the ill effects of this are far more permanent.
And the big breakthrough in 1995 was that we finally have discovered the causation that explains the 100 year old mystery of why grasslands' soils contain vastly more sequestered soil carbon than forests' soils. More than all the biomass on the planet and atmospheric carbon combined! And that new discovery was Dr Sarah Wright's discovery of Glomalin, (
Little Known Glomalin, a Key Protein in Soils) and several other scientists including Dr Christine Jones and Dr Kristine A. Nichols in the field discovery of what has been termed the liquid carbon biochemical pathway for carbon in the soil of which glomalin is only one link of a long chain.
Glomalin, the Unsung Hero of Carbon Storage
Liquid carbon pathway unrecognised
Keep in mind those last two have done field trials that are now being used by early adapters in agriculture already! That information is now decades old, meaning there are ordinary farmers that have successfully used this science to improve their land management for decades already. So it is not only repeatable by soil scientists, it is repeatable by laymen in the field without scientific training.
This is not some mythical hocus pocus, and it is time the rest of the AGW climate scientists peered beyond their closed silos and saw what's out there and currently available to help reverse AGW.
Some have. But this biggest problem is the same merchants of doubt campaign that obfuscates the science of climate change and fuels denialism is also at work vigorously obfuscating the soils science for agricultural change as a mitigation strategy.
Too often I see very obvious flaws in studies designed to minimize the perceived potential of this new paradigm. But that might be obvious to me because it is well within my silo, but it often is not nearly so obvious to a climate scientist whose silo is physics.
For example. You look at a study and find that NPK fertilizers or biocides are used, then you know they haven't studied this new paradigm at all, but rather are studying the carbon sequestration potential of the old paradigm. That's well known, modeled by the Roth C model for climate scientists, and at least 2 orders of magnitude smaller than the liquid carbon pathway. Usually even a net loss! But with certain improvements can be a fairly tiny net gain. Still, no improvement can compare it to the LCP.
You would be well in your rights to ask why this is so obvious to me. That's because of the research done on the glomalin producing arbuscular mycorrhizal fungi and inorganic chemical fertilizers.
Role of Mycorrhizal Symbioses in Phosphorus Cycling
You can see the plant AMF symbiosis trades carbon for phosphorus (and other nutrients too). This is what drives the LCP pumping vast quantities of carbon deep in the A and B horizons of the soil profile, rather that the Roth C which models the decay of biomass at the surface O horizon in the soil profile.
But there is more to it. Because once you add NPK fertilizers to the soil, this symbiosis becomes superfluous, and instead parasitic. Its a feedback mechanism.
Phosphorus and Nitrogen Regulate Arbuscular Mycorrhizal Symbiosis in Petunia hybrida
But we can turn it back on again too!
The Use of Mycorrhizae to Enhance Phosphorus Uptake: A Way Out the Phosphorus Crisis
As long as we use NPK fertilizers to supply plant nutrition, then we have shut down the LCP and instead sequester carbon 2 orders of magnitude slower! But if we instead use this new paradigm to supply plant nutrition, we activate the LCP and soil carbon rises on average rate of 5-20 tonnes CO2e /ha/yr!
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