Spectral diversities of chromophoric dissolved organic matter in paddy field water adjacent to black soil regions of Northeast China

, with DOM dominated by humic acid and protein-like substances. The peak of the EEM spectrum has an average frequency shift difference of about 20 nm compared to non black soil areas. CDOM content is higher in rice paddy water than in irrigation channels and natural paddy water, influenced by microbial degradation, soil processes, and human inputs. These research results are conducive to optimizing irrigation management, improving water quality and enhancing the level of rice cultivation in the black soil. This combined detection and correlational analysis method effectively identified CDOM sources, offering valuable insights into DOM dynamics in agricultural irrigation systems.