为了探究互花米草入侵影响下闽江河口湿地土壤中氨氧化微生物的群落结构及多样性特征，利用高通量测序技术对闽江河口互花米草不同海向入侵阶段湿地(BF:入侵前的光滩;SA M:入侵1～2年的互花米草湿地;SAM:入侵6～7年的互花米草湿地)土壤中的氨氧化古菌(AOA)和氨氧化细菌(AOB)的群落结构及多样性进行了分析。结果表明:互花米草入侵影响下湿地土壤中AOA的OTUs、Chao1指数和Shannon指数均显著高于AOB。互花米草海向入侵降低了土壤中AOA的群落丰富度(OTUs和Chao1指数)和AOB的群落多样性(Shannon指数)，但增加了 AOA的群落多样性和AOB的群落丰富度。不同入侵年限土壤中的奇古菌门(Thaumarchaeota)均是AOA的绝对优势菌门，但AOB在BF和SA M 土壤中均以泉古菌门(Crenarchaeota)占优(＞90％)，而在SAM中以变形菌门(Proteobacteria)占优;不同入侵年限土壤中的Nitrosopumilus均是AOA的优势菌属(＞98％)，而未分类菌属均是AOB的优势菌属(＞90％)。互花米草入侵增加了样本间微生物的空间异质性(尤其是AOB)，这主要与互花米草较强的拦沙促淤能力增加了环境因子的空间异质性有关。互花米草海向入侵影响下AOA对湿地土壤氨氧化过程起着主导作用。互花米草海向入侵主要通过显著改变土壤pH、EC等理化因子以及氮养分条件而间接影响氨氧化微生物的群落结构及多样性。
Effects of Spartina alterniflora invasion on ammonia-oxidizing microbial communities in marsh soils of the Min River estuary
To explore the differences in community structure and diversity of ammonia-oxidizing archaea(AOA)and ammonia-oxidizing bacteria(AOB)in marsh soils at different invasion stages of Spartina alterniflora,the mudflat(BF,before invasion)and the S.alterniflora marsh after seaward invasion for 1～2 years(SA M)and 6～7 years(SAM)in Shanyutan of the Min River estuary were investigated by the high-throughput sequencing method.Results showed that,as affected by S.alterniflora invasion,the richness and diversity(represented by OTUs,Chao 1 index and Shannon index)of AOA in marsh soils were significantly higher than those of AOB.The seaward invasion of S.alterniflora reduced the richness of AOA(represented by OTUs and Chao1index)and the diversity of AOB(represented by Shannon index),but increased the diversity of AOA and the richness of AOB in marsh soils.The AOA in soils of different invasion stages was predominated by Thaumarchaeota.Differently,the AOB in soils of BF and SAM were predominated by Crenarchaeota(＞90％),while those of SAM was predominated by Pseudomonadota.Nitrosopumilus was the dominant bacterial genus in AOA and its relative abundance in soils of different invasion stages exceeded 98％.By comparison the unclassified bacterial genera were the dominant bacterial genus in AOB and its relative abundance in soils at different invasion stages exceeded 90％.The seaward invasion of S.alterniflora increased the spatial heterogeneity of microbial community composition among samples in marsh soils(especially AOB),which was primarily due to the increased spatial heterogeneity of environmental factors caused by strong siltation of S.alterniflora.This study found that the AOA predominated the process of ammonia oxidation in soils of different seaward invasion stages of S.alterniflora.The seaward invasion of S.alterniflora altered the physio-chemical properties(e.g.,pH and EC)and N nutrient conditions in marsh soils,which greatly influenced the structure and diversity of ammonia-oxidizing microbial communities.
ammonia-oxidizing microorganismshigh-throughput sequencingcommunity structureSpartina alternifloraMin River estuary
万方数据
维普
