The response of Cladocera assemblages and size structure to multiple stressors in three Kawartha lakes (Ontario) over the last 200 years)
Bibliographic record
Abstract
The Kawartha lakes region has experienced many impacts from human activities since the European settlement in early 1800s including damming, logging, agricultural activities, fisheries, urbanization, and the introduction of exotic species. The temperature has also increased with regional warming by over a degree Celsius. In this study I used the cores collected from a previous paleolimnological study that sought to understand how primary production changed in these lakes over the last ~200 years in three Kawartha region lakes (Cameron, Pigeon and Stoney lakes) using changes in diatoms and subfossil pigments. The previous study concluded that all three lakes experienced cultural eutrophication, beginning in the early 1800s, with only Cameron Lake potentially experiencing a less nutrient-rich conditions since c. 1940 according to the diatoms. This study assessed the cumulative impact of the multiple stressors on subfossil cladoceran over the last ~200 years by analysing the Cladocera assemblages and the changes in the size structure of Bosmina and Daphnia species. Major restructuring of cladoceran assemblages occurred c. 1830 in all three lakes with increases in the abundance of Chydorus brevilabris, suggesting that damming in c. 1830 was an important factor. Pigeon Lake remained stable in cladoceran assemblages after damming while Cameron and Stoney lakes exhibited increases of ~20-30% abundance of pelagic Daphnia spp. c. 1940-50s. The inconsistency in the timing of Daphnia spp. rising among lakes indicates potential interactions between environmental changes related to climate change, eutrophication, and other anthropogenic stressors. A recent return of Cladocera composition to pre-industrial conditions was seen in Cameron Lake. Changes in size of the dominant Bosmina and Daphnia spp. showed little consistency among lakes. These results support previous findings that nutrient enrichment related to multiple factors has resulted in large and significant changes to Kawartha region lakes. This information provides the context for setting realistic restoration goals.
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 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 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".