Effects Of Different Organic Materials On Humus Properties In Black Soil

The humic substances (HS) originated from microbial decomposition of plant and animal residues represent the most important component of SOM, is universally recognized to be essential for environment and productive soil, So it is one of the hot issues of international affairs. The amendment of soil with organic materials is an environmentally-friendly option, contributing to produces beneficial effects on the chemical, biochemical and physical quality of soil and its plant nutrition capacity. In this paper, the pot experiment was conducted to study the effect of the different organic materials on the combined states of humus, the structure of humus in black soil and combined forms of humus in black soil aggregation. The objectives of that was to provide evidences for diagnosis technique of organic materials and sustainable development of agriculture. The results showed as follow:(1) Compared with control treatment(CK), application of herb residues increased contents of loosely combined soil humus substances, and significantly higher than CK in the first year, after five years used of animal excrement increased the content of loosely combined markedly. The ratio of HA and FA of loosely combined was significantly difference in the first year. E4/E6of every treatment was also significantly difference in the first year. The content of unitedly combine humus of organic materials were all notable lower than CK in the first year, but significant higher than CK three year later, E4/E6indicated that obvious difference until the fifth year, among them, herb residues, animal remnant significantly higher than others, and there were no significant differences among them. There were no difference in the content of the stably combined, but the composition was different, Compared to CK, the content of tightly was increased visible after application of organic materials a year later. The ratio of loosely and tightly showed herb residues dramatically enhanced the ratio, woody residues and animal excrement was observably lower than CK in the first year, and there was no obvious difference with the time going on.(2)Differential thermal analysis(TG-DTA),Elemental Analyzers and Infrared Spectrometer was used to study the effects of the different organic materials on the property of humus in black soil. The results of TG-DTA showed Stability of aliphatic structure of herb residues-HA was the most strong, and stability of animal remnant was the lowest. Compared with control treatment (CK), apart from herb residues, other organic materials decreased condensation of aromatic ring of HA, and there was difference among different treatments. Stability of aliphatic structure of animal remnant-FA was the lowest, and herb residues increased aliphatic structure of FA, at the same time, stability of it was enhanced. Application of organic materials resulted in decrease of condonsation of aromatic ring of FA, but enhanced condensation degree of humin linked to clay (HMc), and there was difference among various treatments. Use of organic materials reduced stability of aliphatic structure of HMc, and the role of animal remnant was the most obvious. Elemental Analyzers showed compared with control treatment (CK), after five years application of organic materials resulted in significant decrease of carbon (C) and hydrogen (H), but enhanced condensation degree and content of nitrogen containing group, and the role of herb residues was the most obvious. Apart from animal excrement, others organic materials significantly increased nitrogen (N) of HA, The order of oxygen (O) content in different organic materials HA was: woody residues>herb residues>animal excrement>CK>animal remnant, and it was remarkable different among different treats. Application of organic materials reduced condensation degree of FA, and the role of herb residues was the most obvious, at the same time, it increased N of FA. The order of C content in different organic materials FA was:herb residues>woody residues>CK>animal remnant>animal excrement, the order of C content was:animal remnant>animal excrement>CK>woody residues>herb residues, and it was remarkable different among different treats. Use of organic materials resulted in significant decrease of C and H, but enhanced content of O of humin linked to iron(HMi), and the role of herb residues was the most obvious, at the same time, herb residues increased N of HMi. Aromaticity and Oxidation degree of humin linked to clay (HMc) was enhanced after application of organic materials. There were different effects on the elemental composition of humus due to application of different organic materials. Infrared Spectrometer showed 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 of humin linked to iron(HMi), but increased aliphatic compounds. Results showed there were different effects on the structure of humus due to different organic materials. Compared with CK,application of organic materials decreased aliphatic compounds of HA and FA, and the role of plant residues was the most obvious.For 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 HMi, but increased aliphatic compounds.(3) The interaction of soil aggregate with humic substances (HS) is important for fertility and soil carbon sequestration, So it is one of the hot issues of international affairs and Low-carbon Society. Compared with control treatment(CK), application of organic resources significantly increased content of loosely combined in>2mm and content of stably combined, but there were markedly differences among organic resources. Woody residues made loosely and unitedly and stably combined forms of humus in1-0.5mm aggregates higher than others, at the same time, unitedly and stably combined in0.5-0.25mm of woody residues were the highest. Animal excrement significantly increased unitedly and stably combined in2-lmm. And herb residues enhanced stably combined in>2mm obviously. Used of animal remnant resulted in significant increase of tightly combined, whereas markedly decreased tightly combined in2-lmm. There were different effects on optical property of combined forms of humus among organic resources, and significant relationship was observed between0.5-0.25mm and loosely combined forms of humus.