Variation in radial growth patterns of <i>Pseudotsuga menziesii</i> on the central coast of British Columbia, Canada
Bibliographic record
Abstract
Radial growth of trees in mountainous areas is subject to conditions associated with changes in elevation. We present ring-width chronologies for Douglas-fir trees (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) at nine sites spanning low to high elevations in the Bella Coola area of the central coast of British Columbia, near the northern limits of the species distribution, and investigate the variation in tree-ring growth patterns in relation to different elevations, using principal component (PC) analysis. We find that the first PC, which represents 55.6% of the total variance, reflects a common growth response at sites of different elevation. Response function analysis indicates that growing season precipitation is the major factor in controlling tree-ring growth. This factor explains more of the variance in low-elevation sites than it does in high-elevation ones. Temperature in August of the preceding year shows a negative relationship to ring-width growth. The second PC represents 16.7% of the total variance and reveals a distinct difference in growth response between low- and high-elevation sites. The length and temperature of the growing season seem to play an important role in tree-ring growth at sites of high elevation. Comparison of the Bella Coola records with those from southern Vancouver Island suggests that growing season precipitation influences growth of Douglas-fir on a macroregional scale, but other factors such as temperature modify the growth response at the limits of the distribution of the species.
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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 | 0.001 |
| 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 | 0.000 |
| Scholarly communication | 0.001 | 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".