Responses of sequential and hierarchical phenological events to warming and cooling in alpine meadows.

Xine Li,Tsechoe Dorji,Lili Jiang,Yang Zhou,Amy M Iler,Mingyuan Du,Xinquan Zhao,Yaoming Li,Liang Zhao,Yingnian Li,Shujuan Cui,Caiyun Luo,Jichuan Duan,Haishan Niu,Qi Wang,Josep Peñuelas,Shiping Wang,Guojie Wang,Zhenhua Zhang,Lirong Zhang,Fanyu Meng ,Xiaoyu Bao

doi:10.1038/ncomms12489

Abstract

Organisms' life cycles consist of hierarchical stages, from a single phenological stage (for example, flowering within a season), to vegetative and reproductive phases, to the total lifespan of the individual. Yet phenological events are typically studied in isolation, limiting our understanding of life history responses to climate change. Here, we reciprocally transfer plant communities along an elevation gradient to investigate plastic changes in the duration of sequential phenological events for six alpine species. We show that prolonged flowering leads to longer reproductive phases and activity periods when plants are moved to warmer locations. In contrast, shorter post-fruiting leaf and flowering stages led to shorter vegetative and reproductive phases, respectively, which resulted in shorter activity periods when plants were moved to cooler conditions. Therefore, phenological responses to warming and cooling do not simply mirror one another in the opposite direction, and low temperature may limit reproductive allocation in the alpine region.

Highlights

Organisms’ life cycles consist of hierarchical stages, from a single phenological stage, to vegetative and reproductive phases, to the total lifespan of the individual
Plant growth and reproduction depend on the same internal resource pool[10,11], and plants allocate a small percentage of their total resources to sexual reproduction in arctic and alpine regions[12], presumably because they live in harsh environments with a short time window to complete their life cycles
Our results show that the temperature sensitivities of flowering duration to warming and post-fruiting leaf duration to cooling are greater compared with other phenological stages

Summary

Introduction

Organisms’ life cycles consist of hierarchical stages, from a single phenological stage (for example, flowering within a season), to vegetative and reproductive phases, to the total lifespan of the individual. Given the harsh abiotic environment in alpine habitats, we expect that warmer temperatures will reduce constraints on allocation to sexual reproduction, in which case we expect longer reproductive phases and activity periods. Our experiment provides insight into how plants may adjust sequences of hierarchical phenological events within the life cycle (Fig. 1) to warmer temperatures expected under future climate change in addition to temperature anomalies, such as short-term cooling events[18,19]. By examining plastic responses in phenological duration to both warmer and cooler temperatures, our study improves our understanding of the basic role of temperature in shaping the relationships among phenological events in the plant life cycle, a need that has been highlighted by the widespread effects of climate change on phenological events[20]. We find that warming significantly prolongs the duration of flowering, which is primarily responsible for longer

Methods

Results

Conclusion