Humic Substances Under Varied Agro-Ecological Units of Jammu and Kashmir

A study was carried on soils developed under varied agro ecological units of J&K under different climatic conditions. The physicochemical properties of the soils were determined and organic matter fractionation was carried out following standard methods. The micronutrient cat ions and their complexation with Humic and fulvic acids were also carried out. Humic and fulvic acids were subjected to IR studies. The result revealed that there was a distinct effect of major environmental factors namely rainfall and altitude on the distribution of soil humus into humic acids and fulvic acids fraction as well as the HA:FA ratio. Soil humus fractions decreased with increasing depth of soil irrespective of the agro climate zone studied. Humic substances had relatively high conc. of oxygen containing functional groups per unit weight. The total acidity Carboxylic and phenolic hydroxyl groups of Humic and fulvic acids showed more or less similar content in the soils of different agro climatic conditions. The potentio-metric titration curves of all the Humic and fulvic acids showed sigmoidal nature with two inflection points showing their weak acidic nature.