ECONOMIC ANALYSIS OF NUTRIENT MANAGEMENT PRACTICES FOR WATER QUALITY PROTECTION
Bibliographic record
Abstract
The main purpose of this study was to evaluate the effect of alternative cropping systems on farm net returns, and nitrate-N and sediment yields in Thomas Brook Watershed (TBW). The study involved integrated bio-physical and economic optimization modelling. Crop yield and nitrate-N pollution response functions were estimated and then used in trade-off analysis between farm returns and environmental quality improvement. Five crop rotation systems were evaluated for seven fertilizer levels under conventional tillage (CT) and no-till systems (NT). Nitrate-N leached, as well as estimated maximum economic rate of N (MERN) fertilizer level and marginal abatement costs depended on crop type, rotation system, and tillage type. The most cost effective cropping systems that met restrictions on Health Canada maximum limit on nitrate-N in water included corn-corn-corn-alfalfa-alfalfa under NT for corn-based cropping systems, potato-winter wheat-carrot-corn under CT for vegetable horticulture-based and potato-barley-winter wheat-potato-corn under NT for potato-based cropping systems.
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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 | 0.002 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| 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".