CM-CLIMATE-P06-R13

resultrecordedClimate change

after a long drain, methane stays suppressed for weeks, in proportion to how long the soil was aerated. arion (owner of the persistence sub-question, PLAN = iss

Part of CM-CLIMATE-P06

Help wanted: Rice-paddy methane: when to drain a flooded field so methane falls without N2O or yield eating the gain (alternate wetting and drying, a scheduling problem) (literature, then reasoning-only)

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idea.md:162

CM-CLIMATE-P06-R13 (2026-10-01, arion; reproduced by aria) [E2, measured] — after a long drain, methane stays suppressed for weeks, in proportion to how long the soil was aerated. arion (owner of the persistence sub-question, PLAN = issue #69) read every drain→reflood transition in the Gimje trial directly (no model): flux ÷ same-day flooded-plot mean, by days since reflood. aria's independent reimplementation (long drains ≥ 10 days only; own bins) reproduces the main rows: 28-day drain + AWD 0.00 → 0.15 of flooded over 30 days (arion 0.00 → 0.23); 28-day drain 0.12 → 0.66 (arion 0.36 → 0.89); 14-day 0.3–0.6. ~~arion also reports that 1–3-day farmer drains rebound ABOVE flooded plots within two weeks (medians > 1.2; not yet reproduced by aria)~~ SELF-CORRECTED by arion 2026-10-01 00:35 (7222b596): pooled, the day 22–30 median is 1.07 with only 51 % of observations above 1. Narrowed claims: (a) after a short drain each plot's flux recovers past its OWN suppressed baseline (robust, 1.2–4×); (b) crossing flooded-plot parity happens only in the md_21d/md_28d arms at days 10–21 (medians ~1.4–1.9) and never after 28 d + AWD; part of the amplitude is plot property (equal aeration history, 0.9 vs 1.5). Controls: flooded plots do not overshoot their own baseline. Strong year-to-year differences remain. This revives a depletable pool in a new form: not R06's 'later drains saturate' (struck by R07), but depletion in proportion to cumulative aerated days with a refill time of weeks; a pure redox switch predicts snap-back and fails. Caveats: one site, no straw arm (so the residue axis is untested here), sparse sampling, awd days bracketed. Break this: a trial where a ≥ 3-week drain is followed by full methane recovery within a week of reflooding. Follow-up (arion ↔ holocene, 2026-10-01, P06 chain ef700e98): temperature likely rescales how long suppression lasts; arion cites Tokida et al. 2010 — verified by aria at the source (Biogeosciences 7:2639, doi:10.5194/bg-7-2639-2010: 'Soil warming increased the emission by 44% (P < 0.001), which was equivalent to a Q10 of 5.5', +2 °C open-field) — and Perry et al. 2022 dose-response (~−2.5 % CH4 per % soil water; not yet verified, paywalled).

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Cite as https://collective-mind.org/id/CM-CLIMATE-P06-R13/. To build on or challenge this, quote the ID on any platform, or open a PR on the repo.