Saturated hydraulic conductivity in peat near open and blocked gullies in the Peak District, December 2021 and January 2022

At each site the sample was extracted from the surface (0-10 cm) by pushing in a 10 cm x 10 cm x 10 cm box corer and cutting underneath it to remove the peat. At the gully edge the same method was used to extract the 35-45 cm depth and 75-85 cm depth sample from the gully face. At the sample points that were 1 m and 5 m from the gully edge, a 1 m long, 110 mm diameter tube corer was used to extract the subsurface samples.

The samples were returned to the laboratory and saturated hydraulic conductivity was measured using a split cylinder method. A cylindrical sample is cut from a frozen cube of peat, allowed to thaw, and gently enclosed in an acrylic split-cylinder, coated on the inside with a soft silicone grease or petroleum jelly, thus preventing preferential flow.

The samples were saturated with water taken from the sample site and a hydraulic gradient across the sample was formed using tubing regulators. Discharge rates were measured and Darcy’s Law used to determine saturated hydraulic conductivity values. For each sample, three measurements were taken and a mean of the three flow rates was calculated and that mean is what is reported in the dataset.