Effects Of Corn Straw Compost On Soil Physicochemical Characteristics,microbial Diversity And Rice Growth In Saline-alkali Soil

Soil salinization threatens agricultural production,affects crop yields,and causes serious obstacles to agricultural development.Straw is one of the most difficult farm materials to manage nowadays,and abandoning or burning straw waste causes environmental pollution and also wastes straw resources.In order to achieve saline-alkali land improvement while reasonably utilize straw,we sampled soda saline-alkali soil from multiple locations and applied selfprepared corn straw compost(CSC)to the saline-alkali soil at different ratios.Then we analyzed the effects of these soil on saline-alkali-resistant and-sensitive rice cultivates.The results showed that CSC had positive effects on saline-alkali soil restoration,not only by reducing the p H and conductivity,but also by increasing the soil nutrient contents and improving soil structure and microbial activity,providing favorable conditions for crop growth under saline-alkali conditions.Moreover,50% of CSC additive amount was the most effective,and the biomass and yield of rice increased significantly,indicating that CSC significantly promoted plant growth.The highthroughput sequencing results showed that Phyllobacterium thick-walled,Phyllobacterium anamorphicum,Phyllobacterium actinomycetemcomitans,and Phyllobacterium greenish curvilinear phylum became the dominant phylum in saline-alkali soil with different percentage of CSC.And Bacillus thermophilus,Bacillus thermophilus,Bacillus thermomonas and Bacillus became dominant genus,and their abundance increased as the amount of CSC increased.The main findings and conclusions are as follows:1.At rice maturation stage,compared with the untreated soil,the p H and conductivity of saline-alkali soil with CSC decreased,and the nutrient contents e.g.total phosphorus,total nitrogen,nitrate nitrogen,available potassium,total organic carbon and effective phosphorus increased.Except for ammonium nitrogen,the contents of soil nutrients increased with the increase of CSC.The most affected was available potassium,and the least affected was effective nitrogen.Ammonium nitrogen and nitrate nitrogen were not significantly affected.Effective nitrogen,effective phosphorus and total phosphorus,although were not significantly altered,increased with the increase of CSC.The effects on saline-alkali-resistant rice cultivate was significantly better than the sensitive one.2.The agglomerate structures of all soil samples were determined,and the four agglomerate structures of 0.25 mm,0.106 mm,0.053 mm,0.012 mm had relatively higher proportion,and the largest proportion was agglomerate structure of 0.106 mm,and the proportion increased with increase of CSC.3.The applying of CSC to saline-alkali soil with conductivity greater than 2,000 μs/cm had significant restoration effects,while little effect when conductivity was lower than 2,000μs/cm.The p H decreased with the applying of CSC,while urease and sucrase were enhanced.4.In conclusion,CSC had significant improvement effects on soil physicochemical properties,soil structure,microbial diversity and abundance,and significantly increased rice yield.Our results provide theoretical basis and technical support for the improvement of soda saline-alkali land,which is beneficial to the sustainable development of modern agriculture.