Maximizing Carbon Sequestration in Terrestrial Agroecosystems

Im a BM and sealover and Patricio wrote:
...deleted vanity spam...
I like and respect Ann Hagerman and Inderjit. They cited me in this paper. The "organic nitrogen cycle" sounds strange. It is the short circuiting of the classic nitrogen cycle, facilitated by symbiotic mycorrhizal fungi on the tannin producer's roots. Organic nitrogen in decomposing matter does not get mineralized to ammonium or nitrate before being taken up by the plant. The fungal partner mobilizes the recalcitrant organic nitrogen and transfers it to the plant in organic nitrogen form.

Im a BM and sealover and Patricio wrote:
For the carbon cycle, this gets more organic carbon into the soil, rather than returned to the atmosphere as CO2. The plant provides a lot of organic carbon to the fungi partner, who then spreads that organic carbon far and wide in its network of hyphael strands. These ecosystems put a lot of organic carbon into the soil, where most of it sticks around for a while.

Im a BM and sealover and Patricio wrote:
For the nitrogen cycle, this organic nitrogen cycle part of it prevents the emission of nitrous oxide, N2O, by ammonia oxidizing bacteria or by nitrate reducing bacteria. Nitrous oxide is a powerful and important greenhouse gas.

Im a BM and sealover and Patricio wrote:
Ann Hagerman came into tannin biochemistry research because people in her field were convinced that tannins (polyphenols) were selected for in evolution as anti herbivore defenses. I first came across her work in a report she wrote about exceptionally high tannin in a fern species that formed monospecific thickets. Inderjit invited me to publish my own fern thicket polyphenol work in a book he was editing.

Im a BM and sealover and Patricio wrote:
And now Hagerman and Inderjit have followed up with this newest paper. After I read the whole thing, there may be more to say here about it. I love that they cited my work for it. It compensates for the deep wounds of internet troll insults.

Im a BM and sealover and Patricio wrote:
July 23, 2025 - New paper by Bartosz Adamczyk came out (online) 7 days ago. They cite me, of course.

Bartosz Adamczyk et al. 2025. Nitrogen fertilization of boreal forest soil increases soil carbon pool through elevated microbial necromass formation but also modifies tree secondary metabolism. Soil Biology and Biochemistry Volume 209, October 2025, 109917

Im a BM and sealover and Patricio wrote:
Essentially, they show increased soil carbon storage when taiga soil is fertilized with nitrogen. They also showed reduced tannin concentration in foliage of boreal trees fertilized by nitrogen. But the most important "new" finding is how much a little nitrogen fertilizer can increase the amount of dead microbial biomass ("necromass") in soil. I can't wait to read it. I've just heard flattering things about it, and I thrive on flattery. I'll be especially curious to see WHERE they did the experiment - In a "normal" taiga forest, or in a place where permafrost has melted? Watch this space...

Im a BM and sealover and Patricio wrote:
A few of the newest thread-topic-relevant relevant papers to cite sealover...

...deleted vanity spam...

Im a BM and sealover and Patricio wrote:
May 21, 2026 Biogeochemistry Update

Im a BM and sealover and Patricio wrote:
Dr. Randy A. Dahlgren is retired, but he got out TWO papers out THIS MONTH!

He got so many awards and honors while he was in the game, and he still authors new papers... And he cites the papers he and I authored together. Not about tooting our own horn so much as providing the only reference available for the first ones to do it.

Im a BM and sealover and Patricio wrote:

came out May 17, 2026. Z Wang, M Shibata, H Lyu, Randy A. Dahlgren, Y Kuzyakov, T Watanabe, C Zaccone, C Chisambi, and S Funakawa. Depth effects of organic matter stabilization in temperate acidic forest soils. Catena, Volume 271, Article 110248.

Im a BM and sealover and Patricio wrote:
Catena is a highly prestigious soil science journal. Note that the title specifies "acidic forest soils" because plant-soil-interactions in low pH soils was our specialty. For example, our paper in Plant and Soil, 1995, "Intraspecific variation of conifer phenolic concentration on a marine terrace soil acidity gradient: A new interpretation" (Plant & Soil, 1995, volume 171, pages 255-262).

Im a BM and sealover and Patricio wrote:
This new paper in Catena cites our 1998 paper in Biogeochemistry, "Polyphenols as regulators of plant-litter-soil interactions in Northern California's pygmy forest: a positive feedback?" (Biogeochemistry, 1998, volume 41, pages 189-220)

I love being able to brag about the fact that I actually know the biogeochemist Randy Dahlgren.

Im a BM and sealover and Patricio wrote:
In fact, I got to work alongside the genius for about a decade.

Good times! And he's still putting out good papers...

May 2, 2026 Biogeochemistry Update

Im a BM and sealover and Patricio wrote:
The following paper reviews the advances in our understanding of the role of geologically derived nitrogen and phosphorus in global nutrient cycles.

Im a BM and sealover and Patricio wrote:
Mike Deas, Jeff Laird, Stacy Tanaka, and Randy A. Dahlgren. 2024. Geologically derived nitrogen and phosphorus as a source of riverine nutrients. Earth Critical Zone, 1 (2024) 100003

Nitrogen is not a rock.
Nitrogen is not derived.
Phosphorus is not derived.
There is no such thing as 'riverine nutrient'
[quote]Im a BM and sealover and Patricio wrote:
Randy Dahlgren is a genius and highly respected biogeochemist who I had the honor of working with for more than a decade. In 1995, I convinced Randy to let me go with my kids to the field and collect a bunch of rock samples, just in case they might turn out to be the source of nitrogen we were finding in the river water.

Im a BM and sealover and Patricio wrote:
This new review paper cites that work, of course (Holloway et al., 1998, Contribution of bedrock nitrogen to high nitrate concentrations in streamwater. Nature volume 395, pages 785-788). Rush Limbaugh actually cited it on his show when it came out in 1998.

Im a BM and sealover and Patricio wrote:
This new review also reveals how measurement of DISSOLVED ORGANIC NITROGEN has become so important to fully account for nitrogen fluxes and identify vehicles of transport. Of course, it cites the laboratory method that WE developed to analyze for dissolved organic nitrogen (Yu et al., 1994, Determination of dissolved organic nitrogen using persulfate oxidation and conductimetric quantification of NO3-N, Communications in Soil Science and Plant Analysis, volume 25, pages 3161-3169)

Im a BM and sealover and Patricio wrote:
In 1993 I talked Randy into letting Zengshou and I develop a faster method, because the Kjeldahl digest was so damn slow and cumbersome and dangerous.. We would just mimic the Dohrman analyzer with alkaline persulfate oxidation, only to determine organic NITROGEN rather than organic CARBON.

Im a BM and sealover and Patricio wrote:
It is very gratifying to see this paper three decades later. Scientists get it now, and they DO make a point to measure organic nitrogen, in addition to the mineral forms (ammonium, nitrate, nitrite, N2, NOx, etc). In some rivers they had been missing more than half the nitrogen, because it was contained in dissolved organic compounds (amino acids, etc). It is gratifying to see that persulfate oxidation has become widely adopted as a faster, cheaper, safer, and more accurate way to measure organic nitrogen than the Kjeldahl digest. It finally got EPA approval, fifteen years ago I think, so it is a "reportable" method to use for environmental bureaucracy purposes. Scientists didn't wait for EPA approval to adopt it for research long before that.

Im a BM and sealover and Patricio wrote:
Randy Dahlgren is retired now, too. He won just about every award they had to give before he did.

Im a BM and sealover and Patricio wrote:
And I'll be getting back to this thread soon enough to update the "sequestration" topic. It keeps going forward, whether the merchants of doubt succeed at handicapping research funding or not. It doesn't cost much to study it, and it won't depend on Donald Trump's support.

Im a BM and sealover and Patricio wrote
Nutrient cycling dynamics of natural ecosystems can be mimicked in cropping systems to maximize carbon sequestration into soil organic matter, and minimize emissions of nitrous oxide. Tannin (aka polyphenol) chemical ecology provides insights into biogeochemical mechanisms that regulate carbon and nitrogen cycling.

Im a BM and sealover and Patricio wrote:
The convergent evolution of tannin-rich plant communities has occurred on highly-infertile soils throughout the world. To acquire and conserve nitrogen, these plants allocate much of their organic carbon below ground to support symbiotic mycorrhizal fungi associated with their roots. Tannins in plant litter form recalcitrant complexes with protein, immobilizing this organic form of nitrogen and preventing mineralization. Mycorrhizal fungi produce enzymes that mobilize nitrogen from protein-tannin complexes, which is transferred directly to the root in organic nitrogen form. This short circuiting of the mineralization step in the nitrogen cycle prevents emission of nitrous oxide to the atmosphere, and prevents export of nitrate to groundwater or surface water. Allocation of photosynthate below ground to support mycorrhizal fungi also enhances sequestration of carbon into soil organic matter.

Im a BM and sealover and Patricio wrote:
Tannins inhibit the oxidation of ammonium in soil to nitrate by nitrifying bacteria. This minimizes nitrous oxide emission as a by product of microbial nitrate reduction. Nitrogen release from tannin-rich litter is predominantly in the form of dissolved organic nitrogen rather than ammonium or nitrate. Dissolved organic nitrogen adsorbs to soil organic matter, minimizing leaching loss of nitrogen and retaining it in slow release form.

Im a BM and sealover and Patricio wrote:
Tannins inhibit the decomposition of organic matter to substantially increase its mean residence in or above the soil. In the most extreme cases, equatorial rainforests form massive litter layers over acid white sand soils that are virtually devoid of nutrients or roots. One- or two-meters thick layers of litter in various stages of decomposition can accumulate above the mineral soil surface. This is despite warm, wet, well drained conditions that favor rapid decomposition. Exceptionally high tannin content in the vegetation of these forests enables them to create an enduring layer of organic matter above the soil surface, where virtually all the root growth and nutrient cycling occurs with high efficiency, and negligible losses.

Im a BM and sealover and Patricio wrote:
Tannins themselves are the dominant substrate that transforms into soil humic acids. Humic acids enhance soil fertility in many ways, and their mean residence time in soil can be many centuries long. Tannins can comprise more than half the dry weight in foliage of tannin-rich species, and much of this represents sequestered carbon that will remain for a long time as stable soil organic matter.

Im a BM and sealover and Patricio wrote:
We may not want to create thick litter layers above the topsoil in all our croplands. But polyphenol biogeochemistry can still be applied to increase carbon sequestration and decrease nitrous oxide emission. For example, tannin-rich organic matter can be combined with more rapidly decomposable crop residues or manure to slow decomposition and immobilize nitrogen into slowly mineralized organic form, as compost. Crop-mycorrhizal associations could be facilitated to sequester carbon and access recalcitrant soil nitrogen.

Im a BM wrote: According to some new theories, the mass extinction 252 million years ago was initially triggered by Siberian vulcanism, but went on to wipe out life on a much larger scale because rainforests were lost as a "sink" for atmospheric carbon dioxide.

Im a BM wrote: I think it was fifteen years ago when I first read about the quantities of [plant food] emitted to the atmosphere from the disturbed peatlands of Southeast Asia.

Im a BM wrote: An undisturbed peatland is a "sink" for carbon dioxide

Im a BM wrote: Some estimates fifteen years ago suggested that CO2 emissions from the Southeast Asian peatlands being drained for agriculture ALREADY exceeded CO2 emissions from all human use of fossil fuel.

Im a BM wrote: The point is that our fossil fuel emissions are becoming a minority part of anthropogenic CO2 emissions.

Im a BM wrote: The quantity of CO2 emitted directly from burning fuel is now exceeded by the quantity of CO2 emitted due to OTHER human activities, such as deforestation and drainage of wetlands for agriculture.

Im a BM wrote: Climate change itself,

Im a BM wrote: due primarily to increased [abundance of plant food]

Im a BM wrote: Full Focus on Fossil Fuel Fails

Im a BM wrote: If the only approach employed by humans to address climate change is the reduction of fossil fuel combustion, it is doomed to fail.

Im a BM wrote: First, it will fail because it will never happen.

Im a BM wrote:Second, it will fail because even if it happens, it won't be enough.

Im a BM wrote:There are too many other new sources of greenhouse gas entering the atmosphere.

Im a BM wrote: Climate change itself is causing the Earth to increase its natural emissions of carbon dioxide and methane.

Im a BM wrote: The warming of the tundra.

Im a BM wrote: The increased frequency and severity of wildfires.

Im a BM wrote: The decreased capacity of coral reefs to act as a carbon "sink".

Im a BM wrote: Human activity other than fossil fuel combustion results in carbon dioxide emissions that rival those from fossil fuel.

Im a BM wrote: Poor land management provoking loss of soil organic matter to be released as carbon dioxide.

Im a BM wrote: The list goes on of all the things we do beyond fossil fuel to cause more greenhouse gases to warm the planet.

Im a BM wrote: So, the only real hope is to somehow significantly increase the amount of carbon dioxide that gets sequestered from the atmosphere.

Im a BM wrote: Some are inventing technological devices to try to do this.

Im a BM wrote: Others are attempting to enable natural ecosystems to sequester more carbon dioxide.

Im a BM wrote: In theory, if we provided enough bioavailable iron to the sea, it would act as fertilizer for a whole lot more marine photosynthesis to sequester CO2.

Im a BM wrote:Natural ecosystems are often very good at sequestering carbon dioxide.

sealover wrote:
Nutrient cycling dynamics of natural ecosystems can be mimicked in cropping systems to maximize carbon sequestration into soil organic matter, and minimize emissions of nitrous oxide. Tannin (aka polyphenol) chemical ecology provides insights into biogeochemical mechanisms that regulate carbon and nitrogen cycling.

The convergent evolution of tannin-rich plant communities has occurred on highly-infertile soils throughout the world. To acquire and conserve nitrogen, these plants allocate much of their organic carbon below ground to support symbiotic mycorrhizal fungi associated with their roots. Tannins in plant litter form recalcitrant complexes with protein, immobilizing this organic form of nitrogen and preventing mineralization. Mycorrhizal fungi produce enzymes that mobilize nitrogen from protein-tannin complexes, which is transferred directly to the root in organic nitrogen form. This short circuiting of the mineralization step in the nitrogen cycle prevents emission of nitrous oxide to the atmosphere, and prevents export of nitrate to groundwater or surface water. Allocation of photosynthate below ground to support mycorrhizal fungi also enhances sequestration of carbon into soil organic matter.

Tannins inhibit the oxidation of ammonium in soil to nitrate by nitrifying bacteria. This minimizes nitrous oxide emission as a by product of microbial nitrate reduction. Nitrogen release from tannin-rich litter is predominantly in the form of dissolved organic nitrogen rather than ammonium or nitrate. Dissolved organic nitrogen adsorbs to soil organic matter, minimizing leaching loss of nitrogen and retaining it in slow release form.

Tannins inhibit the decomposition of organic matter to substantially increase its mean residence in or above the soil. In the most extreme cases, equatorial rainforests form massive litter layers over acid white sand soils that are virtually devoid of nutrients or roots. One- or two-meters thick layers of litter in various stages of decomposition can accumulate above the mineral soil surface. This is despite warm, wet, well drained conditions that favor rapid decomposition. Exceptionally high tannin content in the vegetation of these forests enables them to create an enduring layer of organic matter above the soil surface, where virtually all the root growth and nutrient cycling occurs with high efficiency, and negligible losses.

Tannins themselves are the dominant substrate that transforms into soil humic acids. Humic acids enhance soil fertility in many ways, and their mean residence time in soil can be many centuries long. Tannins can comprise more than half the dry weight in foliage of tannin-rich species, and much of this represents sequestered carbon that will remain for a long time as stable soil organic matter.

We may not want to create thick litter layers above the topsoil in all our croplands. But polyphenol biogeochemistry can still be applied to increase carbon sequestration and decrease nitrous oxide emission. For example, tannin-rich organic matter can be combined with more rapidly decomposable crop residues or manure to slow decomposition and immobilize nitrogen into slowly mineralized organic form, as compost. Crop-mycorrhizal associations could be facilitated to sequester carbon and access recalcitrant soil nitrogen.

sealover wrote:
July 17, 2026

Newest paper to cite sealover's dissolved organic nitrogen assay method, came out three weeks ago.

Xiao Wei, et al. 2026. Adaptive microbial life-history strategies mediate soil nitrogen cycling across cropping systems. Agriculture, Ecosystems & Environment. Volume 411, 1 November 2026, 110608

sealover wrote:
I need to read it, as well as the newest paper by Fubara et al (2026) to have more to say about how it is relevant to the thread topic.


This brand new paper deserves more attention after I get a chance to read it.

This came out 7 days ago, on the 4th of July, 2026. Maybe it was "magic".

B.A. Fubara, et al. 2026. A review on bioactive compounds mitigating climate change. Discover Chemistry(2026) 3:385

sealover wrote:
It cites my 1995 paper in Nature.

"condensed tannins reduce enteric methane by 15-30% and soil N2O by 30-70%"

sealover wrote:
That is just from one sentence of the abstract. Tannins reduce cow gas (CH4) and soil N2O emissions.

sealover wrote:
This paper deserves more discussion in this thread, as it is very much on topic.

I'm sure the two remaining trolls at climate-debate.com will shit all over it.