The relationship between organic matter, invertebrates, and bacteria in the sediments of Lake Malawi
Bibliographic record
Abstract
In the surface sediments below the oxic-anoxic interface in meromictic Lake Malawi, there is little or no evidence of biological activity. As the water depth increases, even in sediments within the oxic zone microbial activity, as measured by 14C leucine incorporation, decreases; the benthic invertebrates decrease in biomass and diversity; and the amount of detrital material remaining in the sediments increases from <1% at 10 m to >14% at 125 m. This relationship with depth could be owing to several factors. At shallower depths, there is terrestrial material available for bacteria to use, as well as detrital material derived from autochthonous production. This detrital material can be degraded in the sediments by the benthic invertebrates, which release dissolved organic carbon and smaller particles through excretion that bacteria can use. As the water depth increases, the bacteria in the water column are able to degrade much of the planktonic debris, leaving the more refractory carbon particles to settle to the sediment. It appears that when there are enough benthic invertebrates, there is still substantial bacterial activity. As the depth increases, the benthic invertebrates disappear and, although there is still detrital carbon available, the bacteria appear unable to utilize it. We suggest that the benthic invertebrates are essential to the processing of detrital carbon and a shift in the degree of anoxia within the lake could seriously alter the cycling of carbon.
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 | 0.000 | 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".