Effects of aluminum on the structure formation of clayey soils evaluated by soil consistency
1998
Karube, J. (Ibaraki Univ., Ami (Japan). Faculty of Agriculture)
The effects of hydroxy-aluminum on the structure formation of Hachirogata and Kasumigaura hedoro, lake-bottom mud, were evaluated by examining the soil consistency. Aluminum was found to accelerate the coagulation of soil to form a bulky sediment. Under sedimentation, aluminum-added soil showed negative shear-rate thixotropy, suggesting a flocculative structure. The plot in the plasticity chart changed downward by the addition of aluminum, indicating the increase of entrapped water in newly formed soil aggregates without changing water content. The addition of aluminum to fresh soil was more effective for aggregation compared to air-dried soil. During shrinkage, air entered the pores of aluminum-added soil at a higher water content, indicating the formation of larger pores resistant to shrinking pressure, and resulted in a bulky dry soil. Greater effects were found when aluminum was added to humic soil. The addition of aluminum had a stronger effect on Hachirogata hedoro, a montmorillonitic clay, than on Kasumigaura hedoro, a halloysitic clay
Mostrar más [+] Menos [-]Palabras clave de AGROVOC
Información bibliográfica
Este registro bibliográfico ha sido proporcionado por Agriculture, Forestry and Fisheries Research Information Technology Center