Research article2016Peer reviewedOpen access
Biological soil crusts cause subcritical water repellency in a sand dune ecosystem located along a rainfall gradient in the NW Negev desert, Israel
Keck, Hannes; Felde, Vincent John Martin Noah Linus; Drahorad, Sylvie Laureen; Felix-Henningsen, Peter
Abstract
The biological soil crusts (BSCs) in the NW Negev cause local water redistribution by increasing surface runoff. The effects of pore clogging and swelling of organic and inorganic crust components were intensively investigated in earlier studies. However, the effect of water repellency (WR) was not addressed systematically yet. This study investigates subcritical WR of BSCs in three different study sites in the NW Negev. For this purpose, three common methods to determine soil WR were used: (i) the repellency index (RI) method (ii) the water drop penetration time (WDPT) test and (iii) the Wilhelmy plate method (WPM). Furthermore, the potential influence of WR on local water redistribution is discussed and the applied methods are compared. We found the BSC to be subcritically water repellent. The degree of WR may only affect water redistribution on a microscale and has little influence on the ecosystem as a whole. The RI method was clearly the most appropriate to use, whereas the WDPT and the WPM failed to detect subcritical WR.
Keywords
Hydrophobicity; Reduced wettability; Surface runoff; Infiltration; Water repellency index
Published in
Journal of Hydrology and Hydromechanics
2016, Volume: 64, number: 2, pages: 133-140 Publisher: VEDA, SLOVAK ACAD SCIENCES
UKÄ Subject classification
Soil Science
Publication identifier
DOI: https://doi.org/10.1515/johh-2016-0001
Permanent link to this page (URI)
https://res.slu.se/id/publ/84999