Abstract

Ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB) are ammonium oxidising prokaryotes that can drive soil nitrification in wetlands. During the restoration of wetlands, different types of land use soils (agricultural soil [AS], restored wetland soil [RS], and natural wetland soil [NWS]) are present. However, studies on the effects of changes in the types of land use in wetlands during restoration on nitrification and the community composition of AOA and AOB are still not well understood. In this study, the differences in the potential nitrification rate (PNR) and community composition of AOA and AOB in AS, RS, and NWS were compared and discussed. The results indicated that the PNRs in the AS, RS, and NWS were on the same order of magnitude. Nitrification was mainly driven by AOB. High-throughput sequencing results showed that the genus Nitrososphaera of AOA and unclassified_o_Nitrosomonadales of AOB were only detected in the AS. Redundancy analysis (RDA) results indicated that the community composition of AOA was mostly influenced by pH, while TC was the most influential variable on the community composition of AOB. Our study provides a basis for distinguishing the roles of ammonium-oxidising prokaryotes in nitrification and further understanding the changes in nitrifying activity in wetlands during restoration.

摘要

氨氧化古细菌（AOA）和氨氧化细菌（AOB）是铵氧化原核生物，可以驱动湿地中的土壤硝化。在湿地恢复期间，存在不同类型的土地利用土壤（农业土壤[AS]，恢复的湿地土壤[RS]和天然湿地土壤[NWS]）。但是，关于恢复过程中湿地土地利用类型的变化对硝化作用以及AOA和AOB群落组成的影响的研究仍不太清楚。在这项研究中，比较并讨论了潜在硝化率（PNR）以及AS，RS和NWS中AOA和AOB的群落组成的差异。结果表明，AS，RS和NWS中的PNR处于相同的数量级。硝化作用主要由AOB驱动。仅在AS中检测到AOA的亚硝基球菌和AOB的未分类亚硝基鸟。冗余分析（RDA）结果表明，AOA的群落组成主要受pH值的影响，而TC对AOB的群落组成影响最大。我们的研究为区分铵氧化原核生物在硝化中的作用和进一步了解恢复过程中湿地硝化活性的变化提供了基础。