Different organic resources influence combined forms of humus in black soil aggregation

摘要

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. In this paper, the pot experiment was conducted to study the effect of the different organic materials on the combined states of humus in black soil. The results showed as follow: Compared with control treatment(CK), application of organic materials significantly increased content of loosely combined in>2mm and content of stably combined, but there was markedly differences among organic materials. Woody residues made loosely and unitedly and stably combined forms of humus in 1-0.5mm aggregates higher than others, at the same time, unitedly and stably combined in 0.5-0.25mm of woody residues were the highest. Animal excrement significantly increased unitedly and stably combined in 2-1mm. And herb residues enhanced stably combined in >2mm obviously. Use of animal remnant resulted in significant increase of tightly combined, whereas markedly decreased tightly combined in 2-1mm. Optical property combined forms of humus varied among organic materials.