ENSO and frost co-determine decade-long temporal variation in flower and seed production in a subtropical rain forest

Flower and seed production of plants can be greatly influenced by both natural climatic oscillations and local weather extremes. However, owing to the rarity of long-term monitoring studies conducted at a sufficient temporal scale to capture climatic oscillations and the unpredictability of extreme weather events, evidence that demonstrates how these two external forcings act in concert to drive plant reproduction remains scarce. In addition, considerable variation in species’ phenological responses to the external climatic forcings was often observed. Phylogenetic relationships may mediate this inter-specific variation, but previous studies yielded inconsistent results when testing this hypothesis. We monitored the flower and seed production in a subtropical rainforest, Fushan, Taiwan (24°45'N, 121°35'E), for over ten years (since September 2002). In March 2005, a record low temperature (-1.3°C) occurred at Fushan and caused great frost damage to plants. We used weekly phenological rec...