The timing of autumn senescence is affected by the timing of spring phenology: implications for predictive models

Abstract

Autumn senescence regulates multiple aspects of ecosystem function, along with associated feedbacks to the climate system. Despite its importance, current understanding of the drivers of senescence is limited, leading to a large spread in predictions of how the timing of senescence, and thus the length of the growing season, will change under future climate conditions. The most commonly held paradigm is that temperature and photoperiod are the primary controls, which suggests a future extension of the autumnal growing season as global temperatures rise. Here, using two decades of ground- and satellite-based observations of temperate deciduous forest phenology, we show that the timing of autumn senescence is correlated with the timing of spring budburst across the entire eastern United States. On a year-to-year basis, an earlier/later spring was associated with an earlier/later autumn senescence, both for individual species and at a regional scale. We use the observed relationship to develop a novel model of autumn phenology. In contrast to current phenology models, this model predicts that the potential response of autumn phenology to future climate change is strongly limited by the impact of climate change on spring phenology. Current models of autumn phenology therefore may overpredict future increases in the length of the growing season, with subsequent impacts for modeling future CO uptake and evapotranspiration.

Evaluation of the Quality of NDVI3g Dataset against Collection 6 MODIS NDVI in Central Europe between 2000 and 2013

“…Tropical regions and other land areas (e.g., the boreal region in some studies) were recognized as important players in the changing global terrestrial net primary production and carbon balance [5,6]. Changes in onset and cessation of the growing season are interacting with the carbon cycle [3,7,8], thus accurate estimation of plant phenology is essential [9][10][11][12][13]. All of these studies clearly demonstrate the…”

Relationships between Wood Formation and Cambium Phenology on the Tibetan Plateau during 1960–2014

“…However, previous authors found that an earlier leaf flushing resulted in an earlier senescence in two tree species of pedunculate oak (Quercus robur L.) and European beech (Fagus sylvatica L.) in Belgium [22]. The timing of autumn senescence was related to the timing of spring bud-burst by using two decades of ground and satellite-based observations of temperate deciduous forest phenology in the northeastern US [23]. A positive correlation between the SOS and EOS was detected from a satellite-observed normalized difference vegetation index over 1982-2011 in the southwestern TP [42].…”

Temperate and boreal forest tree phenology: from organ-scale processes to terrestrial ecosystem models

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