Effect of extreme acid and alkali treatment on surface properties of soils

Abstract

Effects of natural or anthropogenic soil acidification and alkalization on chemical or biological properties have been studied extensively while little is known about changes in physicochemical characteristics, such as surface area or adsorption energy. To investigate this, samples of six Polish soils (Inceptisols, Mollisols) and three Korean soils (Alfisols, Ultisols) of different origin and mineral composition were acidified and alkalized with elevated concentrations of hydrochloric acid and sodium hydroxide ranging from 0.001 to 1 mol dm—3. Surface properties of these soils were studied. The surface area and average adsorption energy decreased in general in both treatments. The treatments induced the decrease in amount of high and medium energy centers, however the fraction of low energy centers increased. The behavior of surface properties differed from the above at treatments at highest reagent concentrations, especially for Korean soils, rich in clay and iron oxides. The general pattern of the adsorption energy decrease observed in most of the soils indicates that the overall water binding forces become lower after treatments. In this case the soil water may be more available for plants, despite its amount decreases.

Reaction of soil water repellency to artificially induced changes in soil pH

“…In order to affect the soil pH measurement, the soil must store added acid or base, some of which may lead to chemical modifications of soil organic matter and mineral surfaces (Jozefaciuk et al, 2000), which could modify their wetting characteristics.…”

Surface and micropore properties of saline soil profiles

“…From the distribution function one can easily derive an average adsorption energy that characterizes global energetic character of the surface. Surface area and energetic properties of soil surface are highly sensitive indicators of various processes occurring in soils: organic matter accumulation, leaching and oxidation, soil acidification, alkalization, silica accumulation, wetting-drying cycles and many others (Sokolowska, 1989;Chiou et al, 1990;Wilczynski et al, 1993;Pachepsky et al, 1995a;Pennell et al, 1995;Sequi and Aringhieri, 1977;Balard et al, 1997;Tombacz et al, 1998;Hoffmann et al, 1999;Jozefaciuk and Bowanko, 2002;Coradin and Livage, 2003;Sokolowska et al, 1993aSokolowska et al, ,b, 1997Sokolowska et al, , 2000Jozefaciuk et al, 1995Jozefaciuk et al, , 1996Jozefaciuk et al, , 2000Jozefaciuk et al, , 2001.…”