College of Agriculture, University of Calcutta, Calcutta
* Present Address: Member, National Commission on Agriculture, Vigyan Bhavan Annexe, New Delhi.
The optical densities and the behaviour towards electrolytes of humic acids obtained by successive extractions from the humin fraction of soil were studied. The optical densities decrease and the coagulation threshold values increase with the successive extractions. The sorption and desorption of Na-humates of successive extractions on and from clay were also studied.
Humic acids, spectral properties
