Abrupt shifts in phenology and vegetation productivity under climate extremes

摘要: Amplification of the hydrologic cycle as a consequence global warming is predicted to increase climate variability and frequency severity droughts. Recent large-scale drought flooding over numerous continents provide unique opportunities understand ecosystem responses climatic extremes. In this study, we investigated impacts early 21st century extreme hydroclimatic variations in southeastern Australia on phenology vegetation productivity using Moderate Resolution Imaging Spectroradiometer Enhanced Vegetation Index Standardized Precipitation-Evapotranspiration Index. Results revealed dramatic wet extremes dynamics, with abrupt between year changes phenology. Drought resulted widespread reductions or collapse normal patterns seasonality such that many cases there was no detectable phenological during years. Across full range biomes examined, found semiarid ecosystems exhibit largest sensitivity variations, exceeding arid humid ecosystems. This result demonstrated vulnerability potential loss resilience future mega-drought events. A skewed distribution aridity biogeochemical significance because it suggests current drying trends regions will reduce suppress large carbon sink has been reported recent periods (e.g., 2011 La Nina).