A comparison of the carbon dioxide fluxes of two annual cropping systems and a perennial hay field in southern Manitoba over 30 months
Bibliographic record
Abstract
The eddy-covariance method was used to measure net ecosystem productivity over three adjacent fields from 2009 to 2011: two annual cropping systems (oat-canola-oat and hay-oat-fallow) recently converted from perennial cropping, and a perennial hay/pasture. We compared the management practises, determined the net carbon budget, and examined the effects of inter-annual variability. Carbon accumulation began earlier in the spring and continued later in the fall at the perennial site, compared with the annual crop sites, due to a longer growing season and continual plant cover. Cumulative cropping season net ecosystem productivity at the perennial site ranged from 40 to 240 g C m^(-2) because of variable weather. Including harvest removals and manure additions, the perennial site gained 120 g carbon m^(-2) and the annual sites lost 240 and 415 g carbon m^(-2), respectively, over the 30-month period. This indicates that the annual cropping systems would decrease soil carbon at this location.
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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 | 0.001 |
| Science and technology studies | 0.001 | 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".