The distribution of a host‐specific canopy parasite is linked with local species diversity in a northern temperate forest
Bibliographic record
Abstract
Abstract Question Is the spatial distribution and density of the maple spindle gall mite V asates aceriscrumena ( MSGM ) positively correlated with the distribution and density of its host? Is the distribution of MSGM influenced by non‐host species and abiotic factors? Location Temperate mixed hardwood forest stand, H aliburton F orest and W ildlife R eserve, O ntario, C anada. Methods We used the mapped locations of host and non‐host trees to investigate the cause of spatial variation in the density of MSGM within an 8.8‐ha forest plot in central O ntario, C anada. Gall densities were determined from fallen leaves, collected at 20‐m intervals. We used M antel and partial M antel tests to compute the correlation between gall density and several spatially variable biotic and abiotic factors: (1) host density and basal area, (2) density of non‐host stems, (3) overall stem density, (4) stem species diversity and (5) topography. Results The density of leaf galls was weakly correlated with host density and basal area. Although the correlation with host density and basal area was statistically significant, leaf gall density was more strongly correlated with overall tree species richness and overall stem density. Gall densities were highest at the boundaries of neighbourhoods containing high and moderate sugar maple ( A cer saccharum ) densities. Partial M antel tests indicated that the observed spatial correlations held when controlling for the potential influence of topography. Conclusions Based on the spatial relationships documented here, we speculate that the mechanism responsible for the correlation between the MSGM and non‐host stems is parasite‐induced host stress. Separate studies have established a strong negative impact of the MSGM parasite on sugar maple stem growth. We suggest that by weakening the competitive ability of its host, the parasite indirectly promotes local species diversity through competitive release. Given the high diversity and prevalence of leaf gall parasites in mixed hardwood stands, depression of host dominance by leaf parasites may represent an unexplored mechanism for the maintenance of species diversity in northern temperate forests.
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 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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.000 | 0.001 |
| 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, 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".