Response of soil bacterial community to different fertilization patterns in young oasis farmland

Fertilization in farming systems should not only optimize crop yields and soil fertilizer but also maintain soil biodiversity and functions. In young oasis farmland, knowledge regarding soil bacteria respond to fertilization strategies is very limited. We performed a 12-year field experiment to evaluated the effects of organic manure, mineral fertilizer and their combination on a typical young oasis farmland in Northwest China, and quantified soil bacterial diversity and composition by using high-throughput DNA sequencing on the Illumina MiSeq platform. Our results showed that maize yield was highest in the pure organic manure treatment and significantly higher than that of the low mineral fertilizer treatment. Organic manure application significantly increased soil nutrient content, while the organic manure level also positively influenced soil nutrient content. Soil bacterial diversity was more sensitive to the application of organic manure than mineral fertilizer. The PERMANOVA results confirmed that bacterial community composition changed along an organic manure level gradient, which was not observed for mineral fertilizer. Organic manure application promoted the abundance of the copiotrophic group, while the environment resistant group were abundant in the only mineral fertilizer treatments. The present study indicated the critical role of organic manure application for increasing crop yield, soil fertility, and soil bacterial diversity while optimizing the community composition of soil bacteria, emphasizing the contribution and importance of organic manure application to overall soil health.