生物炭对植烟土壤理化特性和真菌群落的影响

Effect of Biochar on Physico-Chemical Properties and Fungal Communities of Tobacco-Planted Soils

为探究生物炭对植烟土壤理化性质和微生物群落的影响,以休耕(FL)和单施化肥(CK)为对照,设置1.5 t/hm^(2)(B1.5)、15 t/hm^(2)(B15)两种生物炭添加量,分析不同用量生物炭对植烟土壤理化性质和真菌群落特征的影响。结果表明:生物炭处理显著提高了土壤pH、含水率、有机质含量和≥0.25 mm团聚体比例,显著降低了土壤容重;团聚体平均重量直径(MWD)、微生物量碳(MBC)和微生物量氮(MBN)含量随着生物炭用量的增加而升高;总体上B15处理的土壤理化性质优于B1.5处理。添加生物炭对土壤真菌多样性指数无显著影响,改变了真菌主要菌门相对丰度,其中B15处理的子囊菌门(Ascomycota)、被孢霉门(Mortierellomycota)和毛霉菌门(Mucoromycota)的相对丰度较CK均显著提高;生物炭的添加还提高了赤霉菌属(Gibberella)、被孢霉属(Mortierella)和球腔菌属(Plectosphaerella)的相对丰度,改变了土壤真菌群落结构,两种生物炭添加量的土壤真菌群落结构相似;冗余分析(RDA)及Mantel检验结果说明,土壤pH、有机质、微生物量氮和≥0.25 mm团聚体是影响植烟土壤真菌群落的主要因素。综上,生物炭添加量为15 t/hm^(2)更有助于土壤生产力的综合优化和可持续发展。

In order to investigate the effects of biochar on physicochemical properties and microbial community of tobacco-planting soil,1.5 t/hm^(2)(B1.5) and 15 t/hm^(2)(B15) biochar additions were set with fallow(FL) and single fertilizer(CK) as the control,and the effects of different amounts of biochar on the physical and chemical properties and fungal community of tobacco-planting soil were researched.The results showed that biochar amendment significantly increased soil pH,moisture content,organic matter content and the proportion of ≥0.25mm aggregates,as well as significantly reduced soil bulk density.The mean mass diameter(MWD),microbial biomass carbon(MBC) and microbial biomass nitrogen(MBN) contents of aggregates increased with the increase of biochar addition.In general,the physical and chemical properties of soil treated with B15 were better than those treated with B1.5.The addition of biochar had no significant effect on the soil fungal diversity index,but changed the relative abundance of major fungal phyla.The relative abundance of Ascomycota,Mortierellomycota and Mucoromycota of B15 was significantly higher than that of CK.The addition of biochar also increased the relative abundance of Gibberella,Mortierella and Plectosphaerella.The soil fungal community structure was changed by biochar,but it was similar at two biochar amendment levels.The results of redundancy analysis(RDA) and Mantel test showed that soil pH,organic matter,MBN and aggregates(≥0.25 mm) were the main factors affecting the fungal community in tobacco-planting soil.In conclusion,the addition of biochar of 15 t/hm^(2) is more conducive to the comprehensive optimization and sustainable development of soil productivity.