Radiocarbon evidence of river transport and food web uptake of old carbon in Lake Athabasca, Canada
Bibliographic record
Abstract
Abstract Rivers are major conduits that connect terrestrial carbon cycling with downstream receiving environments. In large lakes, the utilization of river-transported carbon in biological production remains poorly constrained. Lake Athabasca, the eighth largest lake in Canada, receives inflow from the Athabasca River and a large boreal wetland, the Peace-Athabasca Delta. Radiocarbon (14C) was measured to trace the transport of old carbon into western Lake Athabasca and its influence on a modern lake food web by distinguishing the ages of river and lake carbon pools. The fraction of modern carbon in surface sediments showed river inputs of old organic carbon extended at least 50 km into the lake. Old carbon was incorporated into the food web via surface water plankton, and it subsidized ~ 20–50% of carbon in vertebrate consumers, specifically fish and aquatic-feeding birds. These measurements of old carbon showed extensive river influence in western Lake Athabasca (likely > 1500 km2) and high connectivity of river loads with biological uptake.
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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 | 0.001 | 0.002 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 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".