Coral gardening has become a promising technique for restoring reefs worldwide in the Anthropocene era. The microbiome plays an important role in enhancing adaptive resilience in situ nursery propagation of corals. However, little is known about the response patterns of bacterial community dynamics, co-occurrence networks and assembly processes of different species in coral restoration nurseries over time. Here, we collected two Acropora coral samples from transplanted fragments and source colonies at 1-month and 3-month post-transplantation (May and July 2022) in an upwelling-affected fragmented reef. Full-length 16S rRNA gene sequencing revealed that bacterial communities of coral fragments in nurseries exhibited consistent temporal shifts compared to those of the source colonies. High host specificity was observed in the bacterial community and network structure associated with source colonies. In contrast, for the two coral species within nurseries, there were no differences in bacterial diversity, composition and core microbiome. Stochastic assembly processes were identified as the primary drivers of bacterial communities in all May samples, whereas deterministic processes played a more prominent role in July. Seawater properties (e.g., temperature and ammonium concentration) partially explained the compositional changes in the bacterial communities of these coral samples. Our findings suggested that coral nurseries contributed to the homogenization of bacterial communities in different Acropora corals, despite the apparent temporal dynamics of bacteria. These results enhance our understanding of the coral microbiome, ecological interactions and assembly principles in different host within in situ nurseries.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |