Figure 2 Network visualization of bacterial and fungal communities from different ecosystems. The yellow and green dots indicate bacterial and fungal members, respectively. The yellow and green lines indicate positive and negative interactions, respectively. BB, BG, BS, BT, and BP indicate bacterial community of bare soil, grass, shrub, deciduous forest, and coniferous forest, while FB to FP indicate the corresponding fungal communities. P% indicates the positive interaction proportions while ID (interaction density) indicates number of interactions per unit node.
As shown in Fig. 2, the P% and ID from bacterial and fungal communities of different successional stages varied. The bacterial community P% showed a roughly increasing trend through the successional stages, lowest in grass (0.49) and highest in coniferous forest (0.60). While the fungal community showed a decreasing trend, highest in bare soil (0.60) and lowest in coniferous forest (0.48). Bacterial community ID displayed irregular variation through the different successional stages, ranging from 4.62 (deciduous forest) to 6.85 (coniferous forest). Meanwhile the fungal community ID showed a unimodal trend that was highest in shrub (5.54) and lowest in coniferous forest (4.76).