桂北地区石灰性土壤和红壤中微生物群落结构及功能的差异性研究OA

To elucidate the characteristics of microbial diversity in different forest soil types within the subtropical monsoon region,this study investigated O/A(0～10 cm)and AB(10～30 cm)horizons of limestone soils(LS)and red soils(RS)under forest vegetation in Northern Guangxi.Combining 16S rRNA amplicon sequencing with soil physicochemical property analysis differences in microbial community structure,functional potential,and co-occurrence networks between soil types and horizons are explored.The results showed that:1)Both soil types were dominated by Proteobacteria,Actinobacteria,and Acidobacteria.Compared with limestone soils,RS exhibited higher relative abundance of Acidobacteria.Archaeal communities were predominantly Thaumarchaeota(>76％)in both soils.2)Bacterial and archaeal richness indices were higher in limestone soils and red soils,respectively,though overall alpha diversity showed no significant difference.The O/A horizon displayed higher bacterial richness and diversity than the AB horizon,whereas archaeal richness was greater in the AB horizon.3)Limestone soils bacterial and archaeal networks exhibited higher modularity and information transfer efficiency,while red soils networks demonstrated enhanced node complexity and robustness,reflecting adaptive mechanisms to acidic environments.4)Soil pH,organic carbon(SOC),total nitrogen(TN),and available phosphorus(AP)indirectly regulated microbial functional divergence by modulating resource availability.5)Limestone soils bacteria showed stronger carbon-nitrogen metabolic functions(e.g.,nitrification,aromatic compound degradation),whereas red soils bacteria exhibited enhanced nitrogen fixation capacity.Archaeal functional prediction revealed significantly higher aerobic ammonia oxidation activity in limestone soils and greater methanogenic potential in AB horizons of both soils.