Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.2136/vzj2004.0111
Titel (primär) Mini suction cups and water-extraction effects on preferential solute transport
Autor Köhne, J.M.
Quelle Vadose Zone Journal
Erscheinungsjahr 2005
Department BOPHY
Band/Volume 4
Heft 3
Seite von 866
Seite bis 880
Sprache englisch
Abstract Soil water suction cups used in laboratory solute transport studies may cause undesired perturbations of the flow field. The twofold objective of this study was to test mini suction cups, and to assess the effects of pore water-extraction rate and cup size on preferential water flow and bromide (Br-) breakthrough. Porous ceramic cups of 0.25-cm outer diameter and 1-cm length could extract 1 cm(3) of pore water 17 (34, 38) min from 100% (85%, 70%) saturated loam soil by applying 0.1 (0.3, 0.5) bar suction. The corresponding sampling times for larger cups (0.6-cm diam., 2-cm length) were 3.3, 4.6, and 5.7 min. The smaller cups were subsequently tested for solution extraction of 1-cm(3) samples every 20 min out of the matrix and preferential path (PFP) of a large soil column (24-cm diam., 80-cm high) during a Br- transport experiment. Numerical simulations were used (i) to describe the Br- transport experiment and (ii) to evaluate how preferential Br- transport would be affected by pore solution extraction at different locations in the matrix and the PFP of a loam soil block (20 by 20 by 20 cm3) subject to wet and dry initial conditions. Three-dimensional water flow and solute transport were simulated using the Richards and convection-dispersion equations. The experimental and simulation results revealed a dilemma: while fast solution extraction using larger cups altered the flow field and preferential Br- breakthrough for wet and particularly for dry initial conditions, slower solution extraction using small cups caused negligible perturbation of the flow field, but yielded insufficient resolution of the preferential Br- breakthrough. Sampling in the matrix did not considerably affect Br- transport, and gave sufficient resolution of the matrix Br- peak. This study
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=3535
Köhne, J.M. (2005):
Mini suction cups and water-extraction effects on preferential solute transport
Vadose Zone J. 4 (3), 866 - 880 10.2136/vzj2004.0111