Geochemical factors governing vanadium speciation and mobilisation in technosol eco-engineered from bauxite residue under field conditions
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
The high solubility of oxyanions, such as vanadium (V), in alkaline (pH > 9) bauxite residue (BR) generated from alumina production is one of the major environmental risks associated with BR management. Ecological engineering of BR into soil-like growth media (i.e., technosol) offers a promising solution by irreversibly neutralising alkalinity and improving geochemical stability. However, the mechanisms governing the V fractionation, potential mobility, and bioavailability during this transformation remain poorly understood. Here, we show that in a long-term field lysimeter trial, V in BR technosol is primarily hosted in Fe oxide minerals, particularly hematite, of residual phase, followed by organic and oxide-bound phases. The pH was the key driver controlling V solubility, suggesting the importance of irreversible neutralisation of alkalinity in BR using effective eco-engineering inputs (e.g., organic matter and fertiliser). Co-amendments with organic matter and superphosphate fertiliser were most effective in achieving pH neutralisation and V immobilisation. Organic-V complexation in the OM-treated BR can act as an important sink to immobilise V. Consequently, the long-term pollution risk associated with V in BR technosol is expected to be minimal as the technosol system progressively develops into a stable, circumneutral pH, with soil-like properties capable of supporting long-term vegetation growth. • Ecological engineering of bauxite residue enhances vanadium immobilisation. • Vanadium in BR technosol is mainly bound to hematite in the residual fraction. • Irreversible pH neutralisation reduces V solubility and environmental risk. • Organic-V complexation stabilises vanadium in bauxite residue technosol. • Organic matter and superphosphate were most effective in pH reduction and V immobilization.
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.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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 | 0.000 | 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 it