The Assembly Process of Free-Living and Particle-Attached Bacterial Communities in Shrimp-Rearing Waters: The Overwhelming Influence of Nutrient Factors Relative to Microalgal Inoculation

Abstract

The ecological functions of bacterial communities vary between particle-attached (PA) lifestyles and free-living (FL) lifestyles, and separately exploring their community assembly helps to elucidate the microecological mechanisms of shrimp rearing. Microalgal inoculation and nutrient enrichment during shrimp rearing are two important driving factors that affect rearing-water bacterial communities, but their relative contributions to the bacterial community assembly have not been evaluated. Here, we inoculated two microalgae, Nannochloropsis oculata and Thalassiosira weissflogii, into shrimp-rearing waters to investigate the distinct effects of various environmental factors on PA and FL bacterial communities. Our study showed that the composition and representative bacteria of different microalgal treatments were significantly different between the PA and FL bacterial communities. Regression analyses and Mantel tests revealed that nutrients were vital factors that constrained the diversity, structure, and co-occurrence patterns of both the PA and FL bacterial communities. Partial least squares path modeling (PLS-PM) analysis indicated that microalgae could directly or indirectly affect the PA bacterial community through nutrient interactions. Moreover, a significant interaction was detected between PA and FL bacterial communities. Our study reveals the unequal effects of microalgae and nutrients on bacterial community assembly and helps explore microbial community assembly in shrimp-rearing ecosystems.

Inoculation of microalgae distinctly shapes the structure and enhances the stability of eukaryotic plankton community in shrimp rearing water

“…Our previous studies have shown that microalgae are able to influence the diversity of bacterial communities in shrimp rearing water (Shi et al 2023). In this experiment, the eukaryotic plankton community structure in the cultured water body changed significantly after inoculation with microalgae (Fig.…”

“…1). We speculate that the formation of community differences may be linked in some way to the inoculation of microalgae, and related studies have shown that both T. weissflogii and N. oculata reduce nutrient in shrimp rearing water (Yang et al 2018a;Shi et al 2023), thus putting at risk the reproduction of large-sized community adapted to live at high nutrient levels, and conversely, small-sized community adapted to low nutrient levels reproduce rapidly (Maraóón et al 2007;Li et al 2023). These results suggest that microalgae and nutrient are key factors in shaping the structure of eukaryotic plankton community in shrimp rearing water (Cao et al 2023).…”

“…Ternary plots and heatmaps were employed to elucidate the relative relationships and distributions of dominant species among the three treatments using the 'ggtern' and 'edgeR' packages (Shi et al 2023). The software packages 'edgeR' and 'indicspecies' were used to screen for dominant species in the three treatment groups.…”

“…In our previous study, we uncovered the disparate effects of microalgae inoculation and nutrients on bacterial communities in shrimp rearing water (Shi et al 2023), whereas information regarding eukaryotic plankton is fragment. Consequently, in this study, we inoculated N. oculata and T. weissflogii into the water of Litopenaeus vannamei rearing systems to further study (1) the temporal patterns of nutrient factors, microalgae, and eukaryotic plankton communities in rearing water and (2) the responses of the composition, structure, assembly processes and stability of eukaryotic plankton communities to nutrient factors and microalgae.…”

Microalgae Inoculation Significantly Shapes the Structure, Alters the Assembly Process, and Enhances the Stability of Bacterial Communities in Shrimp-Rearing Water

“…In the previous study [26], we found the unequal effects of microalgae inoculation and nutrients on bacterial communities in water during a 10-day experiment. To validate this phenomenon, we conducted a long-term experimental study.…”