Tom and cc three lists
Thanks for your clarification. The article itself (in Science magazine) is very clear on your point; newness refers to newly recognized.
I learned a good bit more about nitrogen here (and need to learn much more) - re nitrogen’s (huge) importance in biochar optimization. This article gives more importance to high latitude biomass - since more nitrogen is available there than in the tropics. I take this to expand the total global area where biochar can be profitable.
Here is the final paragraph (with a surprising emphasis on carbon storage and climate):
Lastly, the availability of N singly and in combination
with P profoundly limits terrestrial C
storage, with nontrivial effects on global climate
change (4, 46). Our previous work demonstrated
a doubling of ecosystem C storage among temperate
conifer forests residing on N-rich bedrock (7).
Our model indicates that rock N inputs could
make up >29% of total N inputs to boreal forests,
which could help to explain the high C uptake
capacity observed for this biome and partially
mitigate the mismatch of C and N budgets in
Earth system models (3). Historically, weathering
has been viewed as responsive to CO2 enrichment
and climate change over deep geological
time (millions of years) (35). The direct connections
that we draw between tectonic uplift, N
inputs, and weathering reactions therefore emphasize
a role for rock-derived nutrients in affecting
the 21st-century C cycle and climate system.
Earlier there is also discussion of the role of microbes, fungi and roots - all biochar-related topics. I wouldn’t say this article intends to promote biochar, but it should remind us that biochar alone doesn’t ever supply enough nitrogen. There is no discussion in this article of leguminous biomass.
The supplemental (>50 pp) has much more on a detailed model - one of three ways they prove this new understanding of “weathering” (which is mainly microbes and fungi) to release old nitrogen.
The claim of new rock nitrogen is very misleading. The soil rock nitrogen is not primary new nitrogen but recycled old nitrogen fixation. This nitrogen is not present as ammonium, nitrate, or nitrogen in rock minerals, but as organic nitrogen in organic matter that has been buried and metamorphosed in sedimentary rocks like shales, which are clays cooked at varying temperature, pressure, and time.