沼渣施肥对桉树人工林土壤氨氧化古菌丰度和群落结构的影响

Effects of Biogas Residue Fertilization on Abundance and Community Structure of Ammonia-oxidizing Archaea in Eucalyptus Plantation Soil

针对沼渣在桉树集约化经营中的合理利用,为了解桉树人工林种植在氮素生物地球化学循环中的作用,在尾巨桉人工林地布设了沼渣、桉树专用肥和对照CK共3组施肥试验,采用实时荧光定量和变性梯度凝胶电泳方法研究沼渣施肥对桉树人工林土壤氨氧化古菌(ammonia-oxidizing archaea,AOA)丰度和群落结构的影响。结果表明,尾巨桉人工林土壤施用沼渣后对AOA的丰度和群落结构均产生了一定的影响。施用沼渣显著促进了AOA的生长,土壤总氮、有机碳和硝态氮含量均与AOA丰度呈显著正相关(P﹤0.05),与土壤pH和铵态氮以及尾巨桉树高、胸径和材积相关不显著(P﹥0.05)。施用沼渣的尾巨桉人工林土壤AOA的群落结构多样性要比施用桉树专用肥的AOA的群落结构多样性好。

In order to rationally utilize biogas residue in the process of intensive management of Eucalyptus plantation and understand the role of Eucalyptus plantation in the nitrogen biogeochemical cycle,3 treatments,namely biogas residue,Eucalyptus-special fertilizer and an unfertilized control(CK)were carried out in the Eucalyptus plantation soils.The abundance and composition of ammonia-oxidizing archaea(AOA) of Eucalyptus plantation soils were determined using quantitative real-time polymerase chain reaction(qPCR) and denaturing gradient gel electrophoresis(DGGE).The results showed that the application of biogas residue in Eucalyptus plantation had a certain impact on the abundance and community structure of AOA.The application of biogas residue significantly promoted the growth of AOA.The AOA abundance was significantly correlated with the contents of soil organic carbon,total nitrogen and nitrate nitrogen(P < 0.05),and not significantly correlated with soil pH,ammonium nitrogen,tree height,breast diameter and timber volume of Eucalyptus urophlla×E.grandis(P > 0.05).The community structure diversity of AOA in the E.urophlla×E.grandis plantation soil treated with biogas residue was better than that of the AOA with the E.ucalyptus-special fertilizer.