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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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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.
PY - 2022/11/30
Y1 - 2022/11/30
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 skilful 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, 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 skilful 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, 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 - Water Science and Technology
KW - Peat
KW - Hydraulic conductivity
KW - Ksat
KW - Pedotransfer function
KW - von Post
KW - Dry bulk density
U2 - 10.1029/2022wr033181
DO - 10.1029/2022wr033181
M3 - Journal article
VL - 58
JO - Water Resources Research
JF - Water Resources Research
SN - 0043-1397
IS - 11
M1 - e2022WR033181
ER -