Effects of <i>Sphagnum</i> peat and copper sulfate on productivity of a Ferro-Humic Podzol
Bibliographic record
Abstract
Sphagnum peat is an abundant resource in the Quebec boreal zone and can be used to improve water retention in sandy soils of low productivity. Our objective was to select a peat application rate suitable for growing potato (Solanum tuberosum L. 'Superior') and barley (Hordeum vulgare L. 'Chapais') on a ferro-humic podzol. The experiment was conducted in Mistassini, Quebec, from 1994 to 1997. Organic matter content (OMC) of a Parent loamy sand was 2.7–2.9% initially. Peat was applied to small plots in a 2-yr potato and 2-yr barley rotation at rates of 0 (control), 29, 48 and 68 t ha−1 on a dry weight basis. A cupric fertilizer trial (0 vs. 2.2 kg Cu ha−1) was combined with the peat treatments. A yearly potato–barley rotation was also established in a nearby field receiving 25 t peat ha−1. The arable layer of peat-amended soils was stratified into a 5.3- to 14.8-cm thick upper layer (A1) down to the limit of peat incorporation, and an underlying layer (A2), averaging 15 cm in thickness, keeping the original soil properties. The highest tuber yield, but reduced tuber specific gravity, were obtained with the 48 t ha−1 treatment compared with the control and the 29 t ha−1 treatments. Peat rates excceeding 29 t ha−1 reduced yield and quality of the barley crop. The Cu concentration in barley and potato diagnostic tissues decreased as peat rate increased. Copper was needed to counteract the detrimental effects of peat amendments on maturation, yield and quality of barley. At field scale, peat increased the lower limit of soil water content for starting irrigation from 0.12 m3m−3 in the control to 0.15 m3m−3 in the peat-amended soil. Irrigation rate should be augmented at each passage, and frequency of waterings diminished, in peat-amended soils compared with the control, due to increased water storage capacity. Peat improved the productivity of the sandy soil up to 4–5% OMC, but could induce Cu shortage in barley. Key words: Soil water, potato, Solanum tuberosum L., barley, Hordeum vulgare L.
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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 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".