Soil bacterial community composition under different crop-residue managements and long-term field fertilization

The bacterial community structure and diversity changes due to crop-residue management and long-term field fertilization was evaluated using the 16S rRNA marker gene (region V3-V4) using high throughput sequencing. Three different agricultural soil management were used: 1) all crop residue incorporated by conventional tillage each crop cycle, new beds formed after each crop; 2) Wheat and maize straw burned, permanent beds reshaped as need for each crop; 3) both wheat and maize straw chopped and left in place, permanent beds reshaped as needed. All three practices were under two nitrogen field fertilization regimes: 0 kg-urea/ha and 300 kg-urea/ha.