Availability of single spring applications of three sulphur fertilizer sources to grass under humid weather conditions
Bibliographic record
Abstract
Field experiments were conducted to compare the effectiveness of single spring applications of three sulphur (S) fertilizers (powdered and granulated elemental S, and granulated sparingly soluble gypsum) to supply S to tall fescue grass (Festuca arundinacea 'Festorina') under humid weather conditions of coastal British Columbia. The treatments were three rates (30, 60 and 90 kg S ha-1) of each of the three fertilizers and control (No S) in three plots initiated in1997, 1998 and 1999 in different locations in an uniformly managed field. The relative effectiveness of the fertilizers was detected by plant uptake of S since the site was only marginally S deficient resulting in only occasional yield increases. The fertilizers were also evaluated by the increase of inorganic sulphate in the soil. The plant and soil measurements showed that S was available to the plant earlier from the granular gypsum than the elemental forms, and the powdered form was available slightly earlier than the granular form of elemental S. Some uptake of all three fertilizers occurred early in the season, i.e., by the first cut of the crop, showing that elemental S was oxidized relatively quickly. The delayed uptake of S from the granulated elemental S compared with the powdered form reflected the need for the granule to disintegrate before it could be oxidized in the soil. This study showed that S is not always available in soils at the time it is required by plants within a growing season of multiple-cut grass. Knowing the pattern of the release of S from various fertilizer forms in relation to within-season variations of soil S availability and plant requirement of S can provide the basis for optimum amendment decisions.Key words: S fertilizers, elemental S, sulphate-S, crop response, crop S uptake, soil sulphate, SulFer 95
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 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".