Impact of the Kenow wildfire on the form and mobility of particulate phosphorus in gravel-bed rivers at large basin scales: Implications for downstream propagation
Notice bibliographique
Résumé
Landscape disturbance by wildfire in forested source water regions can significantly accelerate fine sediment transport from hillslopes to receiving streams. The mobilization of fine sediment and associated nutrients, such as phosphorus (P) into high quality surface waters, which can drastically increase primary production and cause eutrophication, which can severely degrade water quality for ecosystem and human use. In the present study, abiotic controls on the form and mobility of particulate phosphorus (PP) in fine suspended and ingressed river sediment were examined in several oligotrophic gravel-bed rivers in Alberta, Canada, following the 2017 Kenow wildfire. Suspended sediment samples from seven (burned) study sites within Waterton Lakes National Park and three nearby reference rivers draining unburned watersheds were examined from 2018 to 2020 during environmentally sensitive flow conditions, in addition to ingressed sediment samples from burned sites one year post-fire. A sequential extraction scheme and batch equilibrium experiments were conducted to assess the immediate influence of severe wildfire on the form (non-apatite inorganic P, apatite P, organic P) and mobility (equilibrium phosphorus concentration, EPC0) of PP in these systems, respectively. Sediment geochemistry and particle size characteristics were also investigated. Results of the study show that total concentrations of PP and concentrations of bioavailable PP (NAIP) were significantly higher in sediment from rivers draining burned watersheds compared to sediment from rivers in reference watersheds. Elevated bioavailable PP concentrations in burned river sediment were highly correlated with elevated Mn concentrations, which may have been a significant component of pyrogenic material following wildfire. While there were no significant differences in PP mobility between burned and reference river sediment, maximum mean EPC0 values were observed two years after the wildfire, highlighting the potential legacy effect of wildfire disturbance on this key nutrient within rivers. Sediment from both burned and unburned rivers displayed the potential to act as a source of soluble reactive phosphorus (SRP) to the overlying water column, particularly during low flow conditions. Differences in PP form and mobility between burned and reference river sediment were likely influenced by catchment characteristics and in-stream biogeochemical processes. This thesis provides new insights regarding the impact of wildfire and site-specific abiotic processes on the form and mobility of PP in gravel-bed rivers in high quality source water regions.
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 | 0,000 |
| Communication savante | 0,001 | 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) | 0,000 | 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 ».