Environmental constraints on <i>Didymosphenia geminata</i> occurrence and bloom formation in Canadian Rocky Mountain lotic systems
Bibliographic record
Abstract
The first documented bloom of Didymosphenia geminata in Alberta occurred in 2003, and subsequent field investigations revealed that D. geminata was present in the periphyton of a number of lotic systems, yet did not always form blooms. We sampled 76 sites in Canadian Rocky Mountain National Parks, chosen to provide ranges in exposure to D. geminata propagules and environmental conditions thought to affect D. geminata growth and bloom formation. Generalized linear models were then used to determine environmental constraints on habitat suitability and requirements for blooming and nonblooming populations across the landscape. Didymosphenia geminata was detected at 88% of sites, and of those, 34% had blooms, defined as visible mats of D. geminata stalks. Didymosphenia geminata cell abundance was significantly negatively related to stream velocity, stream order, and total phosphorus concentration, yet there was no significant relationship between D. geminata blooms and any of environmental variables measured. There was a significant negative relationship between ash-free dry mass and temperature when cells were present but blooms absent and a positive relationship between temperature and stalk abundance when blooms were present. Total phosphorus, flow velocity, and temperature were significant environmental correlates of cell abundance, but we detected no thresholds related to D. geminata blooms. The widespread occurrence of D. geminata over 1000s of square kilmetres and close proximity of sites with and without blooms suggests that local rather than regional factors drive bloom development.
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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| 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".