Effects of Long-term Fertilization on Bacterial Diversity and Community Structure Succession in Red Soil
A long-term field experiment was conducted in corn mono-cropping system at the National Agro-Ecosystem Observation and Research Station in Yingtan to investigate the effects of fertilization treatment and year on bacterial diversity and community structure in an upland red soil,in which the treatments included CK(no fertilizer),N(chemical fertilizer)and NSM(chemical fertilizer with straw and manure).Soil samples were collected in the 1st year(Y2011),the 3rd year(Y2013),and the 7th year(Y2017),and high-throughput sequencing technology was used to determine bacterial diversity and community structure.The results showed that the contents of soil organic carbon(SOC),total nitrogen(TN),total phosphorus(TP),and available phosphorus(AP)were significantly increased under fertilization treatments.NSM showed a better effect on soil fertility than N,and the effect became more significant with the increase of fertilization history.Bacterial α-diversity was significantly improved in Y2013 and Y2017 compared with Y2011,and was significantly higher under N and NSM than CK.Principal coordinate analysis and cluster analysis based on Bray-Curtis distance consistently showed that bacterial communities were clustered together primarily through the fertilization year.There was no significant difference in bacterial community structure between different fertilization treatments in the same fertilization year.TP was the most critical factor driving variations in the bacterial diversity and community structure.This study provides the scientific proof for the enhancement of red soil fertility and ecosystem health under organic fertilization from the viewpoint of promoting microbial diversity.
Dryland red soilFertilization historyStraw returningBacterial diversityBacterial community structure