Nutrient uptake during low-level fertilization of a large, seventh-order oligotrophic river
Bibliographic record
Abstract
Uptake of nitrogen (total nitrogen (TN), NH4-N, and NO3-N) and phosphorus (total dissolved phosphorus (TDP) and total phosphorus (TP)) was quantified June through September 2009–2011 using whole-river fertilization in a seventh-order, P-limited river (Kootenai River, Idaho, USA), at discharges up to three orders of magnitude greater than previously studied. Mean uptake length (Sw) and uptake velocity (Vf) values were similar for dosed TDP and NH4; both had steep gradients indicating rapid uptake, while NO3-N did not. TP remained higher than reference levels. TN showed no clear pattern. Autotrophs accounted for 28% of daylight mean NO3-N uptake compared with 72% by heterotrophs. Nutrient uptake was strongly associated with chlorophyll accrual and epilithon growth rates. Mean midsummer epilithon growth and N rates roughly tripled late summer rates. TDP uptake length (Sw = 5.7 km) showed a slow increase with increasing stream order consistent with published findings. Mean TDP uptake velocity (Vf = 32 mm·min−1) was eight times greater than previously seen in smaller streams. Vf (10.9 ± 5 mm·min−1) and Sw (16.8. ± 7 km) for NO3-N increased with increasing river order and discharge.
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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) | 0.000 | 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".