稻鳝种养模式对土壤氨氧化微生物群落多样性和结构的影响OA北大核心CSTPCD

Research on the composition,structure,and diversity changes of soil ammonia-oxidizing microbial communities under the rice-eel breeding model is needed to gain in-depth insights into the impact on key microbes involved in soil nitrogen cycling.In this study,Illumina MiSeq high-throughput sequencing was systematically employed to analyze the community structure and diversity of ammonia-oxidizing microbes[ammonia oxidizing archaea(AOA),ammonia oxidizing bacteria(AOB)and complete ammonia oxidizer(Comammox)]in the rice-eel breeding model.Two treatments were established:conventional rice field and rice-eel breeding treatments.Samples were collected from the central area and the edge of the ditch in each treatment,namely:conventional fertilization in the central area of rice fields(CCS),conventional fertilization in the ditch edge area of rice fields(CMS),rice-eel breeding model in the central area(ICS),and rice-eel breeding model in the ditch edge area(IMS).The results showed that:compared to conventional rice field treatment,the rice-eel breeding model significantly reduced soil pH and decreased the difference in soil organic matter(SOM)and soil total N(TN)contents between the central and edge areas of the rice field,and increased soil potential nitrification rate(PNR);In comparison to the conventional rice field treatment,the rice-eel breeding model markedly increased the abundance of AOA and Comammox Clade-A and Comammox Clade-B,while significantly decreasing the abundance of AOB.Meanwhile,IMS significantly enhanced the community diversity index of AOA,but reduced the community diversity index of AOB.AOA and Comammox promoted soil nitrification rates,while AOB did the opposite;Soil pH,SOM,and available nitrogen(AN)were identified as key environmental factors influencing ammonia-oxidizing microorganisms(P<0.05);The rice-eel breeding model altered the structure of the ammonia-oxidizing microbial community and enhanced communication among these microorganisms,resulting in a more tightly connected internal network.The rice-eel breeding model,by altering soil environmental factors,especially soil pH,SOM,and AN content,significantly influences the composition,structure,and diversity of soil ammonia-oxidizing microbial communities.It enhances interactions among ammonia-oxidizing microbes and exerts a significant impact on key microbes involved in soil nitrogen cycling.