Selected rock powders as sources of nutrients for soil fertilization and maize-wheat grain production in southern Brazil
Bibliographic record
Abstract
Abstract The current study evaluated alternative sources of nutrients to improve the soil fertility status and yield of maize-wheat succession in Southern Brazil. The treatments were: T1: no fertilization; T2: liming with dolomitic marble; T3: alternative liming (AL) with limestone interbedded with shale; T4: AL + 50% P - with Arad natural phosphate (P-ANP) + 50% P – triple superphosphate (P-TSP); T5: AL + 100% P-ANP; T6: AL + 100% P-ANP + 100% K-rich monzogranite; T7: AL + 100% P-ANP + 100% N (50% N from tung pressed cake (N-TPC) + 50% N-urea); T8: AL + 100% P-ANP + 100% K-rich monzogranite + 100% N (50% N-TPC + 50% N-Urea) + 100% S; T9: AL + regional average rate of NPK (5-20-20) formulation. Except for T7 and T8, all treatments received the full recommended rate of N through Urea. Immediate and residual effects were evaluated over 2.5 years (90, 360 and 900 days) on soil fertility and maize - wheat yield. The limestone interbedded with shale released Ca, Mg and corrected soil acidity similarly to dolomitic marble. The fertilization strategies used in T4, T7 and T8 presented the highest cumulative productivities while T3 (U$ = 1223), T9 (U$ = 1174) and T4 (U$ = 1122) resulted in higher profits than the other evaluated fertilization strategies. The limestone interbedded with shale (T3), alone or combined with 50% of P-ANP + 50% of P – TSP (T4) provided the best economical and technical results, highlighting the potential of selected alternative regional sources for soil fertility improvement and plant-nutrients supply.
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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 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 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".