The impact of vegetation on hydraulic conductivity of sandy soil

Abstract

The objective of this study was to assess the impact of vegetation on the hydraulic conductivity of sandy soil at the locality Mláky II at Sekule (southwest Slovakia). The measurements were taken on the surface of a meadow (Meadow site), a 30-year old Scots pine (Pinus sylvestris) forest (Forest site) and a glade (Glade site). In the glade, the measurements were also taken in the depth of 50 cm (Pure sand) to reduce the influence of vegetation on the soil properties. It was found that the unsaturated hydraulic conductivity k<sub>r</sub>(−2 cm) as reduced due to the soil water repellency increased in the same order: Forest soil < Glade soil ≈ Meadow soil < Pure sand, similarly as decreased the water drop penetration time t<sub>p</sub>: Forest soil > Glade soil ≈ Meadow soil > Pure sand, which could refer to an inverse proportionality between the capillary suction and hydrophobic coating of the soil particles. The saturated hydraulic conductivity K<sub>s</sub> increased in the following order: Meadow soil < Glade soil ≈ Forest soil < Pure sand; more than two-times higher K<sub>s</sub> at both the Forest and Glade sites than that at the Meadow site could be the result of both the patchy growth of vegetation with some areas of bare soil at the Glade site and the macropores (dead roots) in more homogeneous humic top-layer at the Forest site. The share B<sub>r</sub> of flux through the pores with radii r longer than approximately 0.5 mm decreased in the order: Forest soil » Meadow soil > Glade soil » Pure sand, revealing the prevalence of preferential flow through macropores (dead roots) in the Forest site and a negligible share of macropores in the Pure sand.

Vegetation impact on the hydrology of an aeolian sandy soil in a continental climate

“…It was more than two times greater in the forest and glade sites that had patchy growth of vegetation than the grassland site. There were some areas of bare soil at the glade site and thinner humic top layer at the forest site in comparison with that at the grassland site (Lichner et al , 2007b).…”

“…Temperatures of 50 °C on the surface of bare soil during a hot summer lasted about 5 h a day. More comprehensive weather data for 2005 and 2006 were presented elsewhere (Lichner et al , 2007b).…”

Linking surface and subsurface properties of biocrusted and non-biocrusted habitats of fine-grained fluvial sediments (playas) from the Negev Desert

“…In contrast to loose sand that does not produce runoff and is therefore characterized by deep infiltration (Hillel and Tadmor, 1962;Kidron, 1999), these fine-grained playa surfaces do not facilitate deep infiltration while readily generating runoff (Blackburn, 1975;Kidron et al, 2012b;Kidron, 2014a). While runoff may take place in humid regions following water repellency (Cerdá, 1997;Lichner et al, 2007), this is not the case in NRS, where runoff is produced following surface pore clogging (Kidron, 2014a).…”

Hydrological responses and soil erosion potential of abandoned cropland in the Loess Plateau, China

“…These changes caused significant responses in hydrological function and soil erosion. Enhanced evapotranspiration (Zhang et al, 2001), soil hydraulic conductivity (Lichner et al, 2007), infiltration (Thompson et al, 2010) and improved soil resistance to erosion were also the consequences (Liu, 1997;Zhu et al, 2010), concurrently with the revegetation. In addition, the connectivity of runoff and sediment source areas was reduced (Molina et al, 2009).…”