Mountain pine beetle and forest harvest effects on hydrologic processes and streamflow in the Alberta Foothills
Notice bibliographique
Résumé
The Alberta Foothills region has experienced an unprecedented mountain pine beetle (MPB) outbreak. The provincial management strategy is to contain the infestation with forest harvest. The landscape becomes a patchwork of dead (MPB grey-attack), alive, and harvested stands. MPB attack affects the water transport in trees and results in the gradual loss of the canopy structure, which has the potential to affect hydrologic processes. Therefore, there is a need to understand MPB and forest harvest effects on runoff generation and the streamflow response, especially in watersheds that provide habitat for the endangered Athabasca Rainbow Trout (ARTR). Research questions addressed in this thesis were: 1) what is the effect of varied canopy cover loss on stand water cycling in the Foothills; 2) what is the effect of forest harvest on streamflow in a Foothills watershed; and, 3) what is the effect of potential streamflow changes from MPB grey-attack and forest harvest scenarios on ARTR fry recruitment in a Foothills stream? Methods included a combination of statistical and hydrological modelling as well as data from the MPB Ecohydrology stand-level study and a long-term dataset from the Tri-Creeks Experimental Watershed (Tri-Creeks) near Robb, Alberta. Tri-Creeks has complex glacial deposits underlain by sedimentary bedrock; a geological setting with large potential for subsurface water storage. In addition, climate variability, especially meteorologically driven changes from the Pacific Decadal Oscillation (PDO), influence streamflow. Results from stand-level water balance models showed root zone drainage from the MPB grey-attack stands were similar to an undisturbed mature lodgepole pine stand. Compensatory increases in evapotranspiration from surviving vegetation (unaffected trees or understory vegetation) were predicted in the grey-attacked stands. The greatest root zone drainage occurred in the harvested stand. Results indicate regional differences in hydrologic processes that generate runoff in MPB and harvested stands. Historical clear-cut harvest within Tri-Creeks sub-watersheds was predicted to result in a significant measurable increase in rainfall-generated peak runoff events and summer runoff. However, increased runoff from harvested watersheds may have been attenuated by the drier antecedent watershed conditions in the warm PDO phase. Climate variability, in relation to antecedent watershed storage, remained a strong control on runoff generation in the watersheds. Watershed disturbance scenarios showed MPB grey-attack produced no effect on simulated streamflow response, while simulated clear-cut harvest (52% watershed area) resulted in 15% greater mean annual water yield than if grey-attack trees were left standing. Increased streamflow from forest harvest above the critical discharge threshold for streambed movement of ARTR spawning substrate during the incubation period was predicted to reduce fry recruitment, but annual fry recruitment was estimated to occur over the 50-year simulated streamflow record. Reduced fry recruitment from forest harvest was not likely to produce measurable change at the population level. Overall, results from this thesis provide better understanding of the MPB and forest harvest effects on hydrologic processes and streamflow in the Alberta Foothills and could factor into decisions about MPB strategies with respect to the endangered Athabasca Rainbow Trout.
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 distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| 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 | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| 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 tête enseignante, 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 ».