Effects of Humic Acid and Different Tillage Measures on Carbon Pool and Microbial Community Structure in Saline Alkali Soil
Rainfall or irrigation crusting at seedling stage of saline alkali soil crops is the main cause of soil environment deterioration.In order to clarify the effects of applying humic acid and cultivation measures at seedling stage on the carbon pool and microbial community of saline alkali soil,three treatments of rotary tillage+humic acid(HA),rotary tillage+shallow loosening at seedling stage+humic acid(QHA),rotary tillage+suppression at seedling stage+humic acid(ZHA)were set through field experiments,and rotary tillage without applying humic acid was used as the control(CK),by measuring soil pH,EC,organic carbon,inorganic carbon and bacterial and fungal community structure,the change rules were revealed.The results showed that the application of humic acid could effectively reduce soil pH,slightly reduce soil inorganic carbon(SIC)content,and increase soil TOC content,and the increase rate of shallow loosening treatment was the most significant,reaching 40.36％.Increasing humic acid application could lead to a small decrease in soil MBC,while shallow loosening and suppression will further increase the decrease;Increasing the application of humic acid could significantly increase K+,increase K+/Na+,greatly reduce Na+damage,and improved the salt tolerance of crops.Correlation analysis showed that microorganisms were closely related to environmental factors,among which Gemmatimonadetes,Planctomycetes,Mortierellomycota and Rozellomycota were significantly positively correlated with soil pH;Acidobacteria,Mortierellomycota,Glomeromycota and Mucoromycota were significantly positively correlated with SIC;Rozellomycota was positively correlated with pH and SIC;Firmicutes and Ascomycota were significantly positively correlated with TOC,Verrucomicrobia was extremely significantly positively correlated with MBC,and Chytridiomycota was significantly positively correlated with active organic carbon.Through comprehensive analysis of various indicators,it was found that the carbon pool and microbia community structure of saline alkali soil were the best under the treatment of increasing humic acid and shallow loosening(QHA)at seedling stage.
Humic acidSaline-alkali soilCarbon poolMicrobial community structure
NETL
NSTL
万方数据
