Comparative Investigation of Total, Recoverable and Bioavailable Fractions of Sediment Metals and Metalloids in the Lagos Harbour and Lagoon System
Bibliographic record
Abstract
This study investigated and characterised concentration of some selected metals and metalloids (As, Cd, Cr, Cu, Co, Fe, Mn, Ni, Pb, Sn, V and Zn) present in surface sediments of the Lagos Harbour (LH) and associated Lagos Lagoon (LG) system using a combination of metal extraction and analytical methods within 26 sampling sites including a control (Apese Lagoon, APL). Sampling was carried out using a Van-veen grab sampler on three occasions (dry seasons 2013, 2014; wet season 2013). The total, recoverable and bioavailable fractions were measured separately by X-ray fluorescence (XRF), Aqua regia (AR) extraction with inductively coupled plasma optical emission spectrometry (ICP-OES) and 1 M hydrochloric acid (1 M HCl) extraction with inductively coupled plasma mass spectrometry (ICP-MS) analysis, respectively. Results were compared with National Oceanic and Atmospheric Administration (NOAA)/Canadian Sediment Quality Guidelines (CSQG) and geochemical spatial distribution maps. Threshold effect level (TEL) were exceeded by total concentration of Cu, Zn and recoverable As across the lagoons. Bioavailable As was below TEL while Ni was associated with the ports in the LH.
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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 | 0.001 | 0.001 |
| 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".