Properties of soil humic substances in fractions obtained by sequential extraction with pyrophosphate solutions at different pHs

Properties of soil humic substances in fractions obtained by sequential extraction with pyrophosphate solutions at different pHs

“…The buried Andosol humic acids also tended to display the same characteristics as those of the Andosol humic acids. In Part I of this study (Fujitake et al 1998), it was indicated that in the four soils the proportion of the humic acid…”

“…at pH 3,5,7,9, 11, and 13). All the humic acids had been used in previous studies by Fujitake et al (1998). A full description of the procedures of extraction and purification of the humic acids was reported in the previous paper.…”

“…In our previous report (Fujitake et al 1998), suitable technique for obtaining a series of humic acids from soils by sequential extraction with pyrophosphate solutions at different pH values was described. This technique gave adequate yields of humic acids obtained with the extractants at pH values spanning from the acid to alkaline region, in order to compare the properties of individual humic acids.…”

Population of Humic Acid Degrading Microorganisms in Andosols under Different Vegetation Types and Grassland Management Regimens

“…The humic acid used in this study was extracted from buried Andosol by sequential extraction with pyrophosphate solution at pH 5, the same method as used in the report of Fujitake et al [12][13][14] . According to Fujitake et al 14) , this humic acid has a high aromatic rate. Yanagi et al 32) reported that humic acids with higher aromaticity have greater resistance to decolorization by a particular fungus.…”

“…Oginosen, Yazu, Tottori prefecture, Japan). Sequential extraction of the humic acid using a pyrophosphate solution (pH 5.0) was carried out according to the method of Fujitake et al 12) .…”