Interaction-based biogeographic patterns of bacteria, archaea and microeukaryotes across complex subtropical coastal waters
Marine bacteria, archaea, and microeukaryotes are key cooperative mediators of global biogeochemical cycles. Recent studies have revealed microbial biogeography in marine ecosystem, however, understandings on biogeographic patterns in the context of taxa interactions covering three domains are scarce and challenging. Using a dense sampling strategy and SSU rRNA genes amplicon sequencing, we investigated the intra-domain and inter-domain interactions and the interaction-adjusted biogeography of bacteria, archaea, and microeukaryotes across subtropical coastal waters with multiple environmental gradients in northern Zhejiang, China. More significant partitioning trends of zone-specific microbial communities were captured by Taxa INteraction-Adjusted (TINA) metric than abundance-based Bray-Curtis. The biogeographic patterns of three microbial domains were highly similar based on TINA. Meanwhile, the topological features of intra-domain networks revealed similar geographic patterns for three microbial domains that the strongest interactions generally occurred in the intermediate disturbed areas. Furthermore, our results found that bacteria-archaea associations dominated the inter-domain network and Thaumarchaeota Marine Group I taxa formed the core nodes essential for the three-domain interactomes. Two distinct microbial modules dominated the ecological networks of inshore and offshore areas. Overall, these findings expand current understanding of the three-domain microbial biogeography and assemblageÂ in subtropical coastal marine ecosystems by taking into account the complex network of potential interactions among microbes.