Verification record

Every claim in this article was checked against the abstracts of the papers it cites, by a separate pass that was given those abstracts and nothing else. A claim marked supported carries the sentence that supports it, quoted verbatim below.

References: 14
Claims checked: 6
Fully supported: 5
Checked on: Oct 28, 2026

Claim by claim

Significant vineyard yield gains from biochar were confined to three Tuscan vineyards using the same 500 C orchard-pruning biochar on acidic to neutral, carbon-poor, non-irrigated soils, with increases of 16 to 67 percent per harvest that persisted ten years after application.
SupportedMeta-analysisMeta-analysis
“Significant yield gains were confined to three Tuscan vineyards amended with the same 500 °C orchard-pruning biochar on acidic to neutral, carbon-poor, non-irrigated soils (+16% to +67% per harvest, persisting ten years after application)”
The abstract directly confirms that significant vineyard yield gains were confined to three Tuscan vineyards under those exact conditions and ranges.
- [1] The use of biochar in agricultural soils: Impacts on vineyard productivity and the potential for carbon capture and sequestration (2026)
Checked by google/gemini-3.8-flash on Oct 28, 2026
Eight site-level comparisons, six of them in humid-temperate, cool or calcareous-alkaline settings, showed no significant vineyard yield response to biochar.
SupportedMeta-analysisMeta-analysis
“eight site-level comparisons, six in humid-temperate, cool or calcareous-alkaline settings, showed no significant yield response”
The abstract directly reports that eight site-level comparisons, including six in humid-temperate, cool, or calcareous-alkaline settings, showed no significant yield response to biochar.
- [1] The use of biochar in agricultural soils: Impacts on vineyard productivity and the potential for carbon capture and sequestration (2026)
Checked by google/gemini-3.8-flash on Oct 28, 2026
Across the reviewed trials, increases in soil water and topsoil organic carbon were more consistent than yield responses.
SupportedMeta-analysisMeta-analysis
“eight site-level comparisons, six in humid-temperate, cool or calcareous-alkaline settings, showed no significant yield response, whereas increases in soil water and topsoil organic carbon were more consistent”
The abstract directly confirms that increases in soil water and topsoil organic carbon were more consistent than yield responses across the reviewed trials.
- [1] The use of biochar in agricultural soils: Impacts on vineyard productivity and the potential for carbon capture and sequestration (2026)
Checked by google/gemini-3.8-flash on Oct 28, 2026
The most robust climate outcome in the review was persistence of the biochar carbon itself: the inert fraction was unchanged after 15 years, with 65 to 89 percent remaining after 100 years.
SupportedMeta-analysisMeta-analysis
“The most robust climate outcome is the persistence of the biochar carbon (inert fraction unchanged after 15 years, 65–89% remaining after 100 years)”
The claim accurately reflects the abstract's findings on the long-term persistence of biochar carbon.
- [1] The use of biochar in agricultural soils: Impacts on vineyard productivity and the potential for carbon capture and sequestration (2026)
Checked by google/gemini-3.8-flash on Oct 28, 2026
The review reports that nitrous oxide and methane reductions from biochar are not robust at field scale and remain undetected in vineyards.
SupportedMeta-analysisMeta-analysis
“N2O and CH4 reductions are not robust at field scale and remain undetected in vineyards”
The review explicitly states that N2O (nitrous oxide) and CH4 (methane) reductions are not robust at field scale and remain undetected in vineyards.
- [1] The use of biochar in agricultural soils: Impacts on vineyard productivity and the potential for carbon capture and sequestration (2026)
Checked by google/gemini-3.8-flash on Oct 28, 2026
A single 16.5 tonne per hectare dry application stores 31 to 42 Mg CO2-eq per hectare over 100 years before life-cycle emissions, and without a yield response the break-even carbon price is 90 to 243 euros per tonne CO2-eq, against a 2026 carbon-removal index of 135.
Partially supportedMeta-analysisMeta-analysis
“a single 16.5 t ha-1 (dry) application stores 31–42 Mg CO2-eq ha-1 over 100 years before life-cycle emissions. Without a yield response, the break-even carbon price for biochar costing €200–500 t-1 is €90–243 per t CO2-eq, against a carbon-removal index of €135 (2026)”
The claim accurately reports the carbon storage and carbon-removal index figures, but omits the specific biochar cost range (€200–500 t-1) required to establish the break-even carbon price.
- [1] The use of biochar in agricultural soils: Impacts on vineyard productivity and the potential for carbon capture and sequestration (2026)
Checked by google/gemini-3.8-flash on Oct 28, 2026

What this does and does not prove

It proves that every DOI cited resolves to a real registered work whose returned DOI matches the one requested, that none of them is retracted, and that each claim has a named sentence in a cited abstract behind it.

It does not prove that the paper as a whole supports the claim. An abstract can overstate its own findings, and a sentence can be read out of context. That is why the quote is printed here rather than summarised: if the check is wrong, you can see that it is wrong.

Evidence grading is automatic and conservative. Anything it cannot classify is marked unclassified rather than flattered upward.