RESPONSE OF PHYSICAL CHEMICAL AND BIOLOGICAL PROPERTIES OF AEOLIAN SANDY RHIZOSPHERE SOIL TO SOFT ROCK.

It is of great significance to improve the aeolian soil in Mu Us Sandy Land by using soft rock for resource recycling and low-carbon environment development. In this study, four kinds of mixed soils with a volume ratio of 0:1 (CK), 1:5 (PS1), 1:2 (PS2) and 1:1 (PS3) were selected as the research objects. The soil comprehensive properties were studied by collecting rhizosphere soil after crop harvest. The results showed that the distribution of large aggregates appeared in the composite soil, and the number of large aggregates increased with the increase of the proportion of soft rock, and the large aggregates were mainly mechanically stable aggregates. The organic matter content of PS2 and PS3 increased by 59.02% and 48.54% compared with CK, and the change trend of soil available potassium was the same as that of organic matter. The content of available phosphorus in the mixed soil increased significantly, with an increase of 86.58%~345.57%. Actinobaciota, Proteobateria, Chloroflexi, Acidobacteriota and Firmicutes were the dominant bacteria in rhizosphere soil, accounting for about 85% of the total number of all microorganisms, and Actinobaciota shows absolute advantages at different classification levels. The diversity index and richness index were higher in PS1 and PS2, and the available potassium content promoted the increase of diversity. Therefore, when the proportion of soft rock is 33.33%, it can be used as a better choice to improve the sandy land, and the comprehensive properties of the soil are better. [ABSTRACT FROM AUTHOR]