Abstract
The characteristics of natural organic matter (NOM) released from a representative forest soil under acidic, neutral and basic conditions were investigated based on their physicochemical properties and activated carbon adsorbability. For physicochemical properties, it was found that as the releasing condition changed from acidic to basic, NOM components possessing larger UV absorbing capability and larger molecular weight were released into water. The DOC concentration of NOM released under basic condition was tens of times larger than that under either acidic or neutral condition. On the other hand, based on the batch adsorption experiments and isotherm data analysis with a modified Freundlich isotherm model, the differences in the adsorbability of the released NOM were also demonstrated. Compared to the NOM released under either neutral or basic condition, the NOM released under acidic condition was less adsorbable, and NOM components with larger molecular weight seemed to be more preferentially adsorbed.
