Spatial Variability of Nutrient Requirements in Fields of the South Peace River Region, Alberta
Bibliographic record
Abstract
Site-specific fertilizer application is pertinent only if there is a significant sub-field variability in nutrient requirements. The variability in soil test recommendations for nitrogen (N), phosphorus (P), potassium (K), and sulfur (S) was measured, along transects across three fields in the South Peace River region of Alberta. Depending on the field and intended crop, site-specific fertilizer application would: (1) increase fertilizer inputs by 4–10 kg ha−1, (2) reduce fertilizer inputs by 5–30 kg ha−1, or (3) redistribute the same amount of fertilizer required for uniform application, differently among nutrients and across the field. Fields with extreme topography are more likely to benefit from site-specific fertilizer application, however, slope position alone would be inadequate to stratify fields for this purpose. Requirements for K were the most sensitive to sub-field variability, followed by those for S, P, and N. Producers in the region may not consider site-specific application because grid sampling may be too costly. Quick and economical ways to determine site-specific fertilizer requirements are needed.
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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 | 0.001 |
| 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 | 0.001 |
| 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".