Vol. 12, Issue 4 (2023)

Author(s):
SP Kale, BD Bhakare and HK Kausadikar

Abstract:
Humic substances are the major fractions (nearly 80%) of soil organic matter, constituting humic acid (HA) and fulvic acid (FA) extracted from soils of different land use patterns viz., agriculture land, forest land, fallow land, pasture land, salt affected land, horticulture land and agroforestry land under varied agroclimatic zones of western Maharashtra (India) were evaluated for their individuality and properties through E4/E6 ratio and functional groups. The HA and FA were extracted from soils and further studied for their functional groups. It was observed that the total acidity (7.92 and 6.85 meq total acidity g^-1 HA and 9.35 and 8.58 meq total acidity g^-1 FA) and functional groups of humic acid and fulvic acid viz. CO₂H group (7.82 and 6.87 meq g^-1 HA and 9.82 and 8.86 meq g^-1 FA), Alcoholic group (7.88 and 6.95 meq g^-1 HA and 8.32 and 7.45meq g^-1 FA) and Phenolic group (6.96 and 5.97 meq g^-1 HA and 7.96 and 6.98 meq g^-1 FA) were recorded higher in soil under Mahabaleswar forest as compared to other land use patterns i.e. conventionally cultivated and fallow land at depths 0-15 and 15-30 cm, respectively. In both humic fractions, carboxylic groups contributed a higher amount of total acidity than phenolic groups. E4/E6 ratio was recorded higher in FA then HA. Soils from fallow land showed lower total acidity than forest land.