Hydraulic properties of rooted soils from Salix sp. pot experiments

¹ Technical University of Denmark, Department of Environmental and Resource Engineering, Building 118 Kgs. Lyngby, Denmark
² Technical University of Denmark, Department of Environmental and Resource Engineering, Building 115 Kgs. Lyngby, Denmark

^* Corresponding author: ireroc@dtu.dk

Abstract

Salix sp. plays a significant role in the natural vegetation succession and may be particularly valuable in the slope stabilization of coastal dunes ecosystems of northern Europe, including Denmark. This study aimed to assess hydraulic properties of rooted soils a 0.18 - 0.5 mm diameter clean quartz sand as a substrate and Salix sp., contributing to understanding of ecological benefits and its potential applications in coastal management. Salix sp. plants were established using cuttings measuring 18 cm in length and 1.0-1.4 cm in diameter, placed in plastic PVC pipes that were 25 cm high and 10 cm in diameter, with fitted lids at the base to retain water during growth. The cuttings were cultivated for four different durations: 30, 60, 90 and 180 days, with four experimental replicates for each date. Hydraulic conductivity was measured by constant head tests. The average hydraulic conductivity values observed at 30, 60, 90 and 180 days were 2.2 x 10^-4 m/s, 1.6 x 10^-4 m/s, 1.8 x 10^-4 m/s, and 1.6 x 10^-4 m/s respectively. This showed a general decrease albeit the values remained within the same order of magnitude. This finding offers valuable insights into the reinforcement mechanisms in coastal systems as they evolve over time.