Response of plant flowering phenology to nutrient enrichment: A meta-analysis

Abstract

Nutrients regulate plant phenology by affecting photosynthetic efficiency, carbon allocation, and ecosystem structure and function. However, the effects of nutrient drivers on shifts in flowering phenology under different environmental conditions remain unclear. Here, we conducted a meta-analysis of 101 published articles to evaluate the influence of different nutrient drivers including nitrogen (N), phosphorus (P) and potassium (K) additions on flowering phenology in experimental studies. The results showed that P and K additions significantly advanced first flowering and extended the duration of flowering, whereas N addition did not affect first flowering. Moreover, the effects of nutrient addition on flowering phenology notably differed under various environmental conditions. With increased aridity index (AI), the extension of N addition on flowering duration and the advancement of last flowering following K addition were more pronounced. Nutrient addition affected flowering phenology more significantly in croplands than in natural terrestrial ecosystems, and all three nutrient additions significantly extended flowering duration. Additionally, interactions P + N were frequently synergistic, whereas interactions P + K were primarily antagonistic. These findings provide new insights into the effects of nutrient drivers on plant flowering phenology and suggest that incorporating nutrient availability into models is crucial for accurately simulating flowering phenology.