Soil-Water Retention Curves From Point to Catchment Scales in the Shale Hills Critical Zone Observatory.

Quantification of soil hydraulic functions is essential to catchment hydropedologic and biogeochemical studies.  Soil water retention was investigated as a function of soil type, landform unit, and soil depth in the forested Shale Hills catchment located in central Pennsylvania.  Soil water matric potential and volumetric moisture content were collected in 2004-2010 at 62 sites throughout the catchment and at depths of 10, 20, 40, 80, 100 cm.  These data were fitted with the van Genucthen and Gardner soil water retention equations.  Fitted parameter values from the retention curves at each site and depth were up-scaled from point to watershed-scale using a hierarchical Bayesian modeling approach.