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Title: Herbarium records provide reliable phenology estimates in the understudied tropics
Plant phenology has been shifting dramatically in response to climate change, a shift that may have significant and widespread ecological consequences. Of particular concern are tropical biomes, which represent the most biodiverse and imperiled regions of the world. However, compared to temperate floras, we know little about phenological responses of tropical plants because long-term observational datasets from the tropics are sparse. Herbarium specimens have greatly increased our phenological knowledge in temperate regions, but similar data have been underutilized in the tropics and their suitability for this purpose has not been broadly validated. Here, we compare phenological estimates derived from field observational data (i.e., plot surveys) and herbarium specimens at various spatial and taxonomic scales to determine whether specimens can provide accurate estimations of reproductive timing and its spatial variation. Here we demonstrate that phenological estimates from field observations and herbarium specimens coincide well. Fewer than 5% of the species exhibited significant differences between flowering periods inferred from field observations versus specimens regardless of spatial aggregation. In contrast to studies based on field records, herbarium specimens sampled much larger geographic and climatic ranges, as has been documented previously for temperate plants, and effectively captured phenological responses across varied environments. Herbarium specimens are verified to be a vital resource for closing the gap in our phenological knowledge of tropical systems. Tropical plant reproductive phenology inferred from herbarium records are widely congruent with field observations, suggesting that they can (and should) be used to investigate phenological variation and their associated environmental cues more broadly across tropical biomes.  more » « less
Award ID(s):
1754584
NSF-PAR ID:
10354820
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
bioRxiv
Volume:
2022.08.19.504574
ISSN:
2692-8205
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Herbarium specimens are increasingly used as records of plant flowering phenology. However, most herbarium‐based studies on plant phenology focus on taxa from temperate regions. Here, we explore flowering phenologic responses to climate in the subtropical plant genusProtea(Proteaceae), an iconic group of plants that flower year‐round and are endemic to subtropical Africa.

    Methods

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