Eutrophication is a serious environmental problem facing lakes worldwide. Phosphorus is a critical indicator and cause of eutrophication. Three alkaline phosphatase-encoding gene families related to phosphorus cycling, especially phoD, have been identified in freshwater ecosystems. However, the dynamic patterns of phoD communities remain underexplored, despite extensive studies on overall bacterial community in large eutrophic shallow lakes.

Researchers from Wuhan Botanical Garden analyzed the phoD community dynamics concerning 

seasonal and eutrophic conditions and the underlying mechanisms in Yilong Lake, which is a typical eutrophic and plateau lake primarily influenced by endogenous nutrient sources. 

In Yilong Lake, the dynamic patterns of diversity, composition, and community assembly of the phoD community exhibited significant seasonal shifts in eutrophication levels. The lake demonstrated a moderate eutrophic state during spring and summer and mesotrophic conditions in autumn and winter.

In water, the dominant genera of the phoD community were Streptomyces and Pseudomonas. Particularly, the relative abundance of Pseudomonas reached its highest level during the summer. The Shannon-Wiener index of phoD communities decreased during the summer but increased as eutrophication levels decreased.

It was noted that eutrophication increased the homogeneous selection process of phoD community assembly in water. The co-occurrence networks showed that the OTUs (Operational Taxonomic Units) in the eutrophic state were more interconnected in water but not in sediment, suggesting a delayed response of the phoD community to eutrophication in sediments. Moreover, pH and temperature were found to significantly influence the phoD community. 

The present study provides new insights into the dynamic patterns of phoD communities in lakes

with fragile ecosystems influenced by eutrophication. 

The research results were published in the Environmental Research under the title "Eutrophication-induced shifts cause diverse responses in thephoDcommunity of a plateau freshwater lake ” It was funded by the National Natural Science Foundation of China.