Abiotic and biotic factors associated with pocket mortality of red pine (Pinus resinosa Ait.) in southern Ontario
Notice bibliographique
Résumé
Red pine ('Pinus resinosa' Ait.) has been planted extensively throughout southern Ontario since the 1920s to restore marginal land to productive use, prevent soil erosion, conserve water resources, and provide timber, educational opportunities and recreation. In recent years, unprecedented rates of mortality in maturing plantations are challenging forest managers in their attempts to adhere to traditional management strategies and to realize expected economic benefits. Although earlier studies linked mortality with various causes, no comprehensive evaluation of red pine mortality was undertaken. This study investigated abiotic and biotic factors associated with pocket mortality at 12 plantations in southern Ontario. Trenches, 2 m deep, were dug in diseased and healthy areas of nine plantations exhibiting pocket mortality, and in three disease-free plantations. Below-ground assessments of soil physical characteristics and rooting were combined with above-ground measurements to compare healthy and diseased sites, plots and trees. Root disease pathogens, ('Armillaria ostoyae' and 'Heterobasidion annosum'), black pineleaf scale ('Nuculaspis californica'), drought and iron deficiency were associated with mortality. Rooting depth was greater on healthy sites than on mortality sites, but there was no significant difference between healthy and diseased plots on mortality sites, nor between living and dead trees in mortality plots, except on Armillaria root disease sites where living trees rooted more deeply than trees that recently died. The most notable and consistent difference between healthy and diseased sites was the alkaline C horizon of disease sites compared with the acidic C horizon of healthy sites. Armillaria root disease was the single most frequent biotic factor associated with decline and the rDNA 5S gene and IGS2 region of several ' Armillaria' spp. were sequenced, and an identification protocol was developed based on novel primers and RFLP analyses. RAPD and ISSR analyses of 'A. ostoyae' isolates from two sites provided evidence of carryover of 'Armillaria' from the original forest, through the agricultural period, to the current red pine plantation, as well as of recolonization of an area from which 'Armillaria' had presumably been removed through cultivation. An experiment investigating the contributions of soil type and genetics to rhizomorph production by 'A. ostoyae' isolates supported a greater inherent genetic component than from soil effects.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,001 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».