Abstract:In order to explore the effects of different organic material types and different shapes of same organic materials on the binding form and composition of soil humus in primary saline and alkaline land, the field experiment was carried out for three consecutive years in the primary saline and alkaline land in the western area of Jilin province, and field sampling and indoor analysis were carried out in this study. The experiment was conducted with five treatments, which were granular straw (KL), normal corn straw (JG), grass (MC), sheep manure (YF) and CK. The experimental results showed that:(1) Compared with the CK treatment, the application of different organic materials increased the soil humus content of the original saline-alkali soil, and promoted the increase of humus content in various combined forms in the soil. There was no significant difference in the content of loosely combined humus among the KL, MC and YF treatments, while the difference was significant in comparison with CK. Organic materials had a great influence on the content of conjugated humus in the combined state, and the difference was significant among the treatments. There was a significant difference in the content of stable combined humus between KL treatment and other treatments, and there was no significant difference among the JG treatment, MC treatment and YF treatment, but the difference was significant compared with CK treatment. The tightly bound humus content of the treatments applied organic materials were significantly different with that of CK, and the difference between KL treatment and JG treatment was significant, but there was no significant difference between other treatments. (2) Different organic materials all could improve the loose/tight ratio and the loose/stability ratio, which was conducive to the renewal of humus and the improvement of soil fertility. (3) There were significant difference in H/F ratio between the treatments applied organic materials and CK, and the increase of H/F ratio indicated that the further condensation of FA into HA with a high degree of aromatization and complex structure, and increased the content of HA, and promoted both the polymerization degree and the humification degree of soil humus. Organic materials could increase the humus content of the original saline-alkali soil and increase the content of humus in combined forms. The effect of different forms of the same organic material was significant difference. In this experiment, the effect of granular straw (normal corn straw was crushed under high temperature and pressure, 2 cm long, 0.5 cm diameter cylindrical particles) was much better than other treatments.