Wefer-Roehl, A., The Blaustein Institute for Desert Research, Ben Gurion University of the Negev, Sde Boker 84990, Israel
Graber, E.R, The Volcani Center, Inst. of Soil, Water and Environ. Sci., Agric. Research Organization, P.O. Box 6, Bet Dagan 50250, Israel
Borisover, M.D., The Volcani Center, Inst. of Soil, Water and Environ. Sci., Agric. Research Organization, P.O. Box 6, Bet Dagan 50250, Israel
Adar, E., The Blaustein Institute for Desert Research, Ben Gurion University of the Negev, Sde Boker 84990, Israel
Nativ, R., Department of Soils and Water, Agriculture Faculty, the Hebrew University, Rehovot 76100, Israel
Ronen, Z., The Blaustein Institute for Desert Research, Ben Gurion University of the Negev, Sde Boker 84990, Israel
Graber, E.R, The Volcani Center, Inst. of Soil, Water and Environ. Sci., Agric. Research Organization, P.O. Box 6, Bet Dagan 50250, Israel
Borisover, M.D., The Volcani Center, Inst. of Soil, Water and Environ. Sci., Agric. Research Organization, P.O. Box 6, Bet Dagan 50250, Israel
Adar, E., The Blaustein Institute for Desert Research, Ben Gurion University of the Negev, Sde Boker 84990, Israel
Nativ, R., Department of Soils and Water, Agriculture Faculty, the Hebrew University, Rehovot 76100, Israel
Ronen, Z., The Blaustein Institute for Desert Research, Ben Gurion University of the Negev, Sde Boker 84990, Israel
Sorption capability of bedrock components from a fractured chalk province was evaluated using ametryn, phenanthrene, m-xylene, 2,4,6-tribromophenol, and 1,2-dichloroethane. Sorption isotherms for the four aromatic compounds were nonlinear on gray (unoxidized) chalk. Over the studied solution ranges, the distribution coefficient decreased by factor of 3 for phenanthrene and m-xylene, a factor 4 for ametryn, and by an order of magnitude for 2,4, 6-tribromophenol. In contrast, 1,2-dichloroethane displayed a linear isotherm. The importance of polar interactions for ametryn sorption was evaluated by normalizing sorption to an "inert" solvent, n-hexane, n-Hexane-normalized sorption of ametryn was much greater than that of phenanthrene, presumably due to ametryn participation in hydrogen bonding interactions. In sharp contrast to sorption to gray chalk, sorption to white (oxidized) chalk is 100- to 1000-fold lower at any given solution concentration. The much greater sorption on gray chalk cannot be explained by specific surface area, clay content, or organic matter content; thus, the nature of the organic matter is considered to control sorption in the chalk samples. Gray chalk sorption capacity estimates for ametryn and 2,4,6-tribromophenol are similar, which, together with evidence of competition for sorption sites, suggests that the limited capacity sorption domain for both compounds is similar. © 2001 Elsevier Science Ltd. All rights reserved.
