Is sediment or pseudofaeces toxicity responsible for the decline of the amphipod <i>Diporeia hoyi</i> in Lakes Erie and Ontario?
Bibliographic record
Abstract
The deepwater amphipod Diporeia hoyi has disappeared from Lake Erie and much of Lake Ontario at depths < 80 m. This amphipod had supplied 20 percent of the fisheries energy budget in the Great Lakes. The exotic mussel Dreissena bugensis now forms most of the benthic biomass above 60 m depth, but Diporeia is absent over large areas where Dreissena are rare. The filamentous bacterium Thioploca ingrica is now common at many sites between 30 and 40 m where Diporeia has disappeared. Fisheries and Oceans, Canada, investigated the causes of the decline by examining the sediment chemistry, bacterial production and conducted sediment bioassays using Diporeia, Hyalella and Microtox® Microtox® showed no evidence of toxicity in sediments now devoid of Diporeia. Amphipod survival and growth was greatest in sediment that rapidly lost its Diporeia population in 1993. Presence of Thioploca had no effect on Diporeia survival. Hyalella was more sensitive than Diporeia to test sediments and to filtered water from mussel cultures. Sediment from sites with dense Dreissena populations had lower Diporeia survival. A diet of mussel pseudofaeces caused significantly lower survival in both Hyalella and Diporeia. The exact mechanism causing lower survival is currently unknown and may be related to a nutritional problem or associated waste metabolites.
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) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 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".