Effects of scale on the assessment of fish biodiversity in the marine strategy framework directive context
Bibliographic record
Abstract
The Marine Strategy Framework Directive is undergoing its second implementation cycle while work is ongoing to promote further harmonization, especially regarding the European Commission standards on datasets, metrics, and thresholds. Even though spatial scales for Biodiversity descriptor criteria concerning fish are set by the Directive at subdivision of region, subregion or region level (depending on the fish species group), the scales of the assessment have never been confirmed across the multiple metrics, taxons and regions. In this work, Descriptor 1 – Biodiversity and Criterion 2 – Population abundance of the species (D1C2) was evaluated and compared for six non-commercial fish species, at five geographical scales in the Portuguese Continental waters, to understand if scales used in the assessment affect species group status and hinder the establishment of adequate monitoring or management measures. For comparability purposes, the methods used were identical to the MSFD; a Breakpoint analysis combined with a Trend analysis of the last five years. Results showed that assessments at Portuguese continental Economic Exclusive Zone level mask local population patterns that were visible when smaller size scales were used, and that each species had different scale requirements. Argentyna sphyraena had low biomass index in the northern region of Aveiro, and species analysed in the Algarve region presented distinct patterns. Downsizing scales revealed that Microchirus variegatus was not in good status – i.e. , below threshold - in the southern coastal area, requiring further attention to understand how pressures are impacting populations locally. Although the overall status of the species was maintained, when species assessment was integrated, smaller sized assessment scales are required to understand how populations respond to pressures locally and therefore how monitoring and management of status and pressures should be implemented. Results highlight the need to consider species biology, ecology and population dynamics to define precise scales of assessment and to identify areas of risk at locally relevant scales.
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 | 0.012 | 0.034 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.001 | 0.003 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".