Application Of Biochar To Soil Improvement Of Maize Farmland In San Jiang Plain

Successive years of farming and irrational application of chemical fertilizer have weakened the soil ecological function and reduced the biodiversity in sanjiang Plain,and the protection and restoration of farmland ecosystem is imminent.Biochar,known as"black gold",has gradually entered the field of view of researchers.With its large specific surface area and porosity,biochar is beneficial to soil quality improvement and regulates the reproduction,vitality and diversity of microbial populations while regulating the physical and chemical properties of soil.In view of this,the establishment of one-dimensional moisture migration and vertical,horizontal infiltration test model parameters and simulation training laboratory soil column,according to 0%of the mass of soil（CK）,1%（B₁）,3%（B₂）and 5%（B₃）one-time add biochar,cultivate 90 d,in 15,30,60,and 90,respectively,to collect four periods of soil samples,The physicochemical properties of soil were measured,and the effects of biochar application with different supplemental levels on the structure of bacteria and fungi in the soil of corn farmland in Sanjiang Plain were studied by Illumina Miseq sequencing technology and redundancy analysis.The relationship between biochar and soil moisture,nutrients and other physicochemical factors as well as microbial community structure was analyzed.The main research results were as follows:（1）With the addition of biochar,soil p H value,organic matter and total phosphorus were significantly increased.In total k,available P and available K soil,alkali-hydrolyzable N（including nitrate N）was significantly decreased,while total N was not significantly changed.Soil original nitrification,nitrogen cycling and biochar addition had influence on soil.（2）Soil,biochar application in low proportion into the level（1%）improved soil bacteria flora diversity and richness,in high proportion into the level（3%～5%）on the contrary,Proteobacteria,Actinobacteria,Acidobacteria and Chloroflexi were the dominant bacteria,and the relative abundance of Proteobacteria and Actinobacteria decreased,while that of Acidobacteria and Chloroflexi increased with biochar input.Kd4-96,Subgroup＿6,Gemmatimonas,Haliangium and Bradyrhizobium were the dominant genera,and the relative abundance of KD4-96,Subgroup＿6 and Blastomonas was increased,while the relative abundance of Haliangium and Bradyrhizobium was decreased.With the increase of biochar content,the richness of soil fungal flora gradually increased and the diversity gradually decreased.Basidiomycota,Ascomycota and Mortierellomycota fungi were the dominant phyla,and biochar application increased the abundance of Basidiomycota while decreased the relative abundance of Ascomycota and Mortierellomycota fungi.Tausonia,Solicoccozyma,Humicola and Mortierella were the dominant genera,The relative abundance of Tausonia and Solicoccozyma increased with the increase of biochar content,while the relative abundance of Humicola and Mortierella decreased.（3）Redundancy analysis showed that soil bulk density,field capacity,p H,organic matter,total nitrogen,total phosphorus,saturation volumetric moisture content changes affect the soil microbial community,field capacity and the volume of saturated water content significantly affected the soil bacteria species abundance,soil bulk density,field capacity and p H significantly influence soil fungi species abundance.These results indicated that biochar application changed soil characteristics and indirectly droved the change of soil microbial community structure.（4）In this study,biochar application increased the abundance of beneficial bacteria genera,such as Haliangium and Bradyrhizobium,and decreased the abundance of common harmful fungi genera,such as Fusarium and Aspergillus.Therefore,the future research will focus on deeply explore the changes of plant functional bacteria and pathogenic bacteria after biochar addition,providing theoretical guarantee for agricultural production.