Using a modelling approach to evaluate nitrogen fertilization best management practices for corn in Ontario
Bibliographic record
Abstract
Root Zone Water Quality Model (RZWQM) and a weather generator (ClimGen) were adapted and tested for use in evaluating the effect of climate variability and best management practices (BMPs) on the fate of fertilizer nitrogen applied to corn grown in southern Ontario. Field data collected from two commercial farm fields were used to evaluate RZWQM simulations. Long-term runs of RZWQM using generated weather data were used to develop annual values for the most economic rate of nitrogen (MERN) for a reference corn site. Year-to-year variability of the MERN was significant, however, the average of the generated annual MERNs was close to current nitrogen recommendations. Foreknowledge of the season's MERN was marginally beneficial in reducing nitrate losses. Modelled BMPs including greater use of rotations, side-dress and split applications of nitrogen reduced long-term nitrate loss by 1.3% to 19.1%. Corresponding corn yield reductions were usually small but in some cases were significant.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 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".