Productivity and diversity of rocky intertidal macroalgae in relation to a seasonally fluctuating environment
Bibliographic record
Abstract
The productivity, diversity and community structure of the intertidal macroalgal community in the vicinity of Bamfield, B.C. Canada were studied over a fifteen month period (June 1982 to August 1983). Four study sites were examined as representative along a gradient of wave exposure. Algal standing crops were estimated at semi-weekly intervals; these data were used to calculate algal diversity and, in conjunction with concurrent measurements of photosynthesis, algal productivity. Fucus distichus was most abundant at the upper levels of the three more sheltered sites where it formed an extensive canopy. The lower shore at the sheltered sites was characterized by a series of spring/summer annual and ephemeral species (Leathesia difformis, Cryptosiphonia wood, Ulva fenestrata , etc.). As wave exposure increased, F. distichus abundance decreased. Mid-shore levels at the exposed site were characterized by an "algal turf" while lower levels were dominated by Hedophyllum sessile Standing crop of all species was greatest in spring/summer and least in winter. At the sheltered sites, diversity was very low in those areas dominated by F. distichus and greater on lower levels of the shore. Diversity was greatest in the mid-shore "algal turf" assemblage at the exposed site and lower in the distichus (upper) and H. sessile (lower) dominated zones. It was proposed that the observed vertical (tidal height), horizontal (wave exposure) and seasonal patterns of algal diversity were the result of the interactive effects of wave action and desiccation stress. Herbivory (by Littorina scutulata and L. sitkana ) and the presence of a F. distichus canopy were secondary influences. Net daily photosynthesis in F. distichus was greatest during the spring and early summer and was positively correlated with water temperature. Photosynthetic rates varied little throughout the year, indicating that daylength, and not photon flux density per se, was more responsible for the observed seasonal differences in net daily photosynthesis. Positive net daily productivity was observed all year, but increased wave action during the fall/winter limited algal standing crops. It was proposed that F. distichus productivity is limited by wave action in the fall and winter and nutrient/desiccation stress during the summer.
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 | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 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) | 0.001 | 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".