Effects of the Different Organic Materials on the Structure and Elemental Composition of Humus in Black Soil

Abstract

Elemental Analyzers and Infrared Spectrometer was used to study the effects of the different organic materials on the structure and elemental composition of humus in black soil. The results showed as follow: Compared with control treatment (CK), application of organic materials decreased aliphatic compounds of humic acid(HA) and fulvic acid(FA), and the role of plant residues was the most obvious. In humin linked to clay (HMc), all the organic materials could increased aliphatic compounds, at the same time, decreased content of aryl-groups C＝C. After five years, used of organic materials decreased content of hydroxyl and saccharide in humin linked to iron(HMi), but increased aliphatic compounds. Compared with CK, after five years, application of organic materials resulted in significant decrease of C and H content, and the role of herb residues was the most obvious. Apart from animal excrement, others organic materials significantly increased N content of HA, and there was significant differences among different treatments. Application of herb residues increased N of FA. The order of C content was: animal remnant>animal excrement>CK>woody residues>herb residues, and no significant differences were observed for this parameter among different treatments. Use of organic materials resulted in significant decrease of C and H, but enhanced O content of HMi , and the role of herb residues was the most obvious, at the same time, herb residues decreased N of HMi. After application of animal excrement and woody residues，the C and N content of HMc were enhanced, and H content of HMc was decreased. Compared with CK, application of organic materials resulted in significant decrease of H content of HMc, and there was significant differences among different treatments.