Fig. 5

Co-occurrence correlation network of the bacterial communities associated with rhizosheath–root system and bulk sand in contrasting seasons. a Visualization of co-occurrence bacterial networks of rhizosheath–root system and bulk sand in summer and winter. Large modules with ≥ 3% of nodes are shown in different colours, and smaller modules are shown in grey; colours are assigned randomly. Network topological attributes are listed in Table 4. b Degree of connection of nodes within each network; results are visualized at the bacterial class level and expressed as Log-transformed average. c Betweenness centrality of nodes calculated for each co-occurrence network; results are visualized at the bacterial class level and expressed as Log-transformed average. d Visualization of the first 20 keystone species identified based on the sum of degree, closeness centrality and betweenness centrality for each node in the four networks; results are visualized at the bacterial class level and expressed as Log-transformed average