Effects of Successive Planting of Eucalyptus Plantations on Tree Growth and Soil Quality

The ultra-short-cycle successive planting of Eucalyptus plantations has caused environmental and social problems, changing the rotation cycle is a very good option to solve this issue. However, effects on growth soil quality after cultivation period are unclear. This study evaluated growth, nutrients, bacterial fungal community structure with an eight-year period. different succession generations (first, second third generation) were selected, tree height diameter at breast measured. Ten indicators nutrients in layers (0–20 cm 20–40 cm) measured, bacteria fungi sequenced high throughput. Results show that there upward trend three generations, reaching highest timber yield third-generation plantation. Soil also showed changes, 0–20 layer, decreased TN, NH4+-N, NO3−-N AK increased AP, particularly for OM TP content. In content NH4+-N slightly soil’s OM, TP, TK significantly. diversity communities significantly, composition changed. Bacterial structures mainly driven by pH, AP factors factors, respectively. Thus, plantings eight years conducive trees. Some returned, microbial increased. Successive brought efficiency economic benefits while maintaining fertility.