TY - JOUR
T1 - Saturated Hydraulic Conductivity in Northern Peats Inferred From Other Measurements
AU - Morris, P. J.
AU - Davies, M. L.
AU - Baird, A. J.
AU - Balliston, N.
AU - Bourgault, M. A.
AU - Clymo, R. S.
AU - Fewster, R. E.
AU - Furukawa, A. K.
AU - Holden, J.
AU - Kessel, E.
AU - Ketcheson, S. J.
AU - Kløve, B.
AU - Larocque, M.
AU - Marttila, H.
AU - Menberu, M. W.
AU - Moore, P. A.
AU - Price, J. S.
AU - Ronkanen, A. K.
AU - Rosa, E.
AU - Strack, M.
AU - Surridge, B. W.J.
AU - Waddington, J. M.
AU - Whittington, P.
AU - Wilkinson, S. L.
N1 - Funding Information:
We are grateful to Bryn Davies, Myles Gould, and Nik Lomax (University of Leeds) for helpful early suggestions about data analysis. We acknowledge funding from a variety of sources, which supported the collection of many of the data reported herein: The Canadian Foundation for Climate and Atmospheric Sciences (awarded to J. M. Waddington); Countryside Council for Wales (now part of Natural Resources Wales; Cors Fochno Hydrological Research and Management Study awarded to A. J. Baird); the Environment Agency of England and Wales (Contract 12078, awarded to A. J. Baird); the European Union LIFE Program (Freshabit LIFE IP project LIFE14/IPE/FI/023, awarded to A.‐K. Ronkanen, who led the University of Oulu's contribution to that project); the European Union Water Joint Programme Initiative (WATERPEAT project, awarded to B. Kløve); the Finnish Cultural Foundation (awarded to M. Menberu); Fonds de recherche du Québec (Groundwater Partnership Research Grant 2010‐HO‐137058 awarded to M. Larocque); Ministère de l'Environnement et de la Lutte contre les changements climatiques (Groundwater Knowledge Acquisition Project grant awarded to M. Larocque); the Natural Environment Research Council of the United Kingdom (NE/S007458/1 awarded to R. E. Fewster; NE/J007609/1, NER/I/S/2001/00712, and NE/G00224X/1 awarded to J. Holden); the Natural Sciences and Engineering Research Council of Canada (RDCPJ 51342‐17, RGPIN 250117‐2003, and RGPIN‐2015‐06744 awarded to M. Larocque; and multiple grants awarded to S. J. Ketcheson, M. Strack, and J.M. Waddington); and the Ouranos Consortium (Grant 5540007 awarded to M. Larocque).
Publisher Copyright:
© 2022. The Authors.
PY - 2022/11
Y1 - 2022/11
N2 - 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.
AB - 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.
KW - K
KW - dry bulk density
KW - hydraulic conductivity
KW - peat
KW - pedotransfer function
KW - von Post
UR - http://www.scopus.com/inward/record.url?scp=85142882302&partnerID=8YFLogxK
U2 - 10.1029/2022WR033181
DO - 10.1029/2022WR033181
M3 - Journal Article
AN - SCOPUS:85142882302
SN - 0043-1397
VL - 58
JO - Water Resources Research
JF - Water Resources Research
IS - 11
M1 - e2022WR033181
ER -