In freshwater ecosystems, submerged macrophytes, as key primary producers, regulate ecological balance through a series of feedback mechanisms and play a critical role in maintaining the clear-water steady state and protecting biodiversity. In recent years, human activities and climate change have intensified global eutrophication, leading to frequent harmful algal blooms that severely threaten submerged macrophyte communities. Algal blooms often cause a rapid decline in the biomass and diversity of these foundational species, thereby impairing the ecosystem services provided by lakes.

Understanding how biodiversity and community functional traits maintain the multidimensional stability of lake ecosystems under global environmental change is essential for safeguarding the vital ecosystem services on which human societies depend.

Recently, a joint research group from the Institute of Hydrobiology (IHB) of the Chinese Academy of Sciences and Yunnan University revealed the key roles of submerged macrophyte species diversity and community phosphorus stoichiometric homeostasis (H_P) in multidimensional stability under algal bloom disturbances, and provided a new perspective for predicting the responses of submerged macrophyte-dominated lake ecosystems to the increasingly frequent algal bloom events today. This study was published online in Journal of Ecology.

To address this research gap, the study employed an internal nutrient loading gradient experiment and integrated three years of seasonal monitoring data (before, during, and after algal blooms) on submerged macrophyte communities in Lake Erhai. It systematically explored how species diversity and functional traits (i.e., H_P) influence multiple dimensions (temporal stability, resistance, resilience, and recovery capacity) and multiple aspects (function, composition, diversity, and functional traits) of submerged macrophyte community stability after algal blooms. Three key findings emerged:

1, Species diversity and community HP showed positive correlations with the temporal stability, resistance, and recovery capacity of community function and composition. This indicates that ecosystems with higher species diversity and community HP exhibit greater resistance and stability against external algal bloom disturbances.

2, No positive correlation was observed between species diversity/community H_P and resilience—negative correlations were even detected in some cases. This suggests that high-biodiversity ecosystems dominated by species with high HP may not facilitate rapid recovery from disturbances.

3, Among the four stability dimensions, there was a strong positive correlation between functional stability and compositional stability. In contrast, the relationship between species diversity stability and the stability of key functional traits (H_P) was complex, implying significant challenges in maintaining stability across multiple dimensions and aspects simultaneously.

This study emphasizes the key roles of species diversity and community stoichiometric homeostasis in driving the stability of lake ecosystems under algal bloom disturbances, and highlights the necessity of prioritizing mechanisms and processes that independently regulate different dimensions and aspects of stability. The findings enhance our understanding of the mechanisms maintaining ecosystem stability against the backdrop of global environmental change and provide crucial empirical evidence for the complex ecological topic of the biodiversity-stability relationship.

(Editor: MA Yun)