Water dispersible colloids and factors influencing their dispersibility from soil aggregates

Molecular Speciation of Phosphorus Present in Readily Dispersible Colloids from Agricultural Soils

“…Masses of colloids were determined gravimetrically by placing 40-mL aliquots of non-ultracentrifuged samples in tared Teflon beakers and drying at 100°C to constant weight (Seta and Karathanasis, 1996). Colloidal TP (TP coll ), molybdate-reactive P (MRP coll ), molybdate-unreactive P (MUP coll ), total organic C (TOC coll ), Fe coll , Al coll , and Ca coll were measured as the difference between their concentrations in the non-ultracentrifuged (<1 mm) and ultracentrifuged (truly dissolved fraction) samples.…”

Review on subsurface colloids and colloid-associated contaminant transport in saturated porous media

“…Besides the well-documented effects of clay mineralogy (e.g. Seta and Karathanasi [34]) and solution ionic strength and pH [27,41] on colloid dispersion, total clay content [94], soil moisture conditions [95], soil management [96] and interactions among these properties have also been shown to affect colloid dispersibility. Actually, interparticle forces such as vander Waals attraction and electrolytic repulsion determine colloidal fines stability.…”

Aggregate Stability in Soil with Humic and Histic Horizons in a Toposequence under Araucaria Forest

“…In soil profiles with lower soil organic matter (SOM) content, the main aggregation agents are Fe and Al oxides. The effect of these minerals on aggregate stability has been attributed to structural cementation, and is a subject extensively explored in the literature (Goldberg et al, 1988;Seta and Karathanasis, 1996;Pinheiro-Dick and Schwertmann, 1996;Barthès et al, 2008;Igwe et al, 2009). However, in soils with lower clay and Fe oxide content, aggregate stability is related to SOM (Six et al, 2002).…”