Bacterial community composition changes independently of soil edaphic parameters with permafrost disturbance
Bibliographic record
Abstract
Abstract. Microbial degradation of frozen organic carbon increases with permafrost thaw, resulting in greater fluxes of the greenhouse gases CO2 and CH4. To examine the effect of disturbance-induced permafrost thaw on microbial communities, we assessed the microbial diversity of soils near a gold mine where thaw was induced by stripping the vegetation and topsoil at Dominion Creek, Yukon, Canada. Bacterial metabarcoding and soil physicochemical parameters were assessed across this disturbance including surface samples and three cores which included active layer and permafrost horizons. Bacterial communities changed in the absence of physicochemical parameter shifts after only 6 weeks of thaw, with a high proportion of active layer indicator species becoming more abundant with permafrost thaw. Three distinct communities emerged: (1) undisturbed active layer, (2) lower active layer, disturbed active layer, and disturbed permafrost samples, and (3) intact permafrost. Community composition shifts correlated with pH, Zn and community cohesion. These results suggest that active layer communities rapidly colonize thawed permafrost, combining with and replacing many resident permafrost taxa. Disturbances may induce a strong microbial community change in permafrost-affected soils before soil physicochemical parameter shifts.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".