Saturated Hydraulic Conductivity in Northern Peats Inferred From Other Measurements

Morris, P. J.; Davies, M. L.; Baird, A. J.; Balliston, N.; Bourgault, M.‐A.; Clymo, R. S.; Fewster, R. E.; Furukawa, A. K.; Holden, J.; Kessel, E.; Ketcheson, S. J.; Kløve, B.; Larocque, M.; Marttila, H.; Menberu, M. W.; Moore, P. A.; Price, J. S.; Ronkanen, A.‐K.; Rosa, E.; Strack, M.; Surridge, B. W. J.; Waddington, J. M.; Whittington, P. et Wilkinson, S. L. (2022). « Saturated Hydraulic Conductivity in Northern Peats Inferred From Other Measurements ». Water Resources Research, 58(11), e2022WR033181.

Fichier(s) associé(s) à ce document :

Prévisualisation	PDF Télécharger (1MB)

Résumé

In northern peatlands, near-saturated surface conditions promote valuable ecosystem services such as carbon storage and drinking water provision. Peat saturated hydraulic conductivity (Ksat) plays an important role in maintaining wet surface conditions by moderating drainage and evapotranspiration. Peat Ksat can exhibit intense spatial variability in three dimensions and can change rapidly in response to disturbance. The development of skillful predictive equations for peat Ksat and other hydraulic properties, akin to mineral soil pedotransfer functions, remains a subject of ongoing research. We report a meta-analysis of 2,507 northern peat samples, from which we developed linear models that predict peat Ksat from other variables, including depth, dry bulk density, von Post score (degree of humification), and categorical information such as surface microform type and peatland trophic type (e.g., bog and fen). Peat Ksat decreases strongly with increasing depth, dry bulk density, and humification; and increases along the trophic gradient from bog to fen peat. Dry bulk density and humification are particularly important predictors and increase model skill greatly; our best model, which includes these variables, has a cross-validated r2 of 0.75 and little bias. A second model that includes humification but omits dry bulk density, intended for rapid field estimations of Ksat, also performs well (cross-validated r2 = 0.64). Two additional models that omit several predictors perform less well (cross-validated r2 ∼ 0.5), and exhibit greater bias, but allow Ksat to be estimated from less comprehensive data. Our models allow improved estimation of peat Ksat from simpler, cheaper measurements.

Type:	Article de revue scientifique
Informations complémentaires:	© 2022. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Mots-clés ou Sujets:	Peat, hydraulic conductivity, Ksat, pedotransfer function, von Post, dry bulk density
Unité d'appartenance:	Centres institutionnels > Centre de recherche en géochimie et géodynamique (GEOTOP) Centres institutionnels > Groupe de recherche interuniversitaire en limnologie et en environnement aquatique (GRIL) Faculté des sciences > Département des sciences de la Terre et de l'atmosphère
Déposé par:	Marie Larocque
Date de dépôt:	09 nov. 2022 12:01
Dernière modification:	09 nov. 2022 12:01
Adresse URL :	http://archipel.uqam.ca/id/eprint/16114

Modifier les métadonnées (propriétaire du document)

Statistiques