Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswa Vidyalaya, Kalyani, (W. B.)
The interaction of urea and ammonia with humic and fulvic acids was studied. It was found that a considerable amount of nitrogen had been fixed by fulvic acids and more fixation occurred in the case of urea treated material. The carboxyl acidity is reduced by this interaction. The nitrogen containing reaction products had higher negative charges and higher electrophoretic mobilities than the original ones. Urea treated humic acid fixed much greater amount of metal ions than the untreated and ammonia treated humic acids.
Humic and fulvic acids, interaction with urea and ammonia, metal ions
