Terrestrial lichen abundance in relation to stand structure and silvicultural history
Bibliographic record
Abstract
Terrestrial lichen has been identified as an important factor contributing to suitable woodland caribou (Rangifer tarandus caribou) winter habitat. Conservation efforts to maintain viable populations of woodland caribou in areas where forest management activities take place will require an understanding of the forest conditions that promote suitable habitat characteristics. \nTwo studies were conducted for this thesis. In the first study, terrestrial lichen abundance and stand structure of naturally disturbed and previously harvested forest stands in northwestern Ontario were measured. Terrestrial lichen abundance (% cover) was relatively low and highly variable, but significantly higher in conifer-dominated (4.28 ? 6.83%), than in deciduous (0.60 ? 1.51%) or mixedwood (0.62 ? 1.01%) stands. No significant difference in lichen abundance was found between naturally disturbed (3.14 ? 5.77%) and previously harvested stands (3.41 ? 6.53%). Lichen abundance was significantly greater in stands with non-organic (5.71 ? 7.75%), rather than organic (2.07 ? 4.14%) soil textures. Among non-organic conifer-dominated stands, negative relationships were observed between lichen abundance and canopy closure, basal area, tree height and crown height. \nIn the second study, terrestrial lichen abundance was compared in twenty-four 20 to 40 year-old stands, previously treated with prescribed burning (PB) or mechanical site preparation (MSP). T-test and Mann-Whitney U test results indicated no strong difference in terrestrial lichen abundance between PB (8.95 ? 8.45%) and MSP (2.37 ? 2.03%) treatments, though confounding effects of dominant tree species composition may have contributed to this result. Among the stand structural characteristics measured, canopy closure exhibited the strongest negative relationship with lichen abundance. Negative relationships were also observed between lichen abundance and crown height and basal area. \nThe results of this study indicate that terrestrial lichen abundance is difficult to predict in conifer-dominated stands of northern Ontario. Terrestrial lichen abundance is strongly correlated with overstory structural attributes, which suggests that forest management activities could potentially influence terrestrial lichen abundance by manipulating stand structure to create understory light conditions that are favourable to terrestrial lichen establishment and growth.
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 | 0.000 | 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) | 0.002 | 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".