[en] Tropical forest phenology directly affects regional carbon cycles, but the relation between species-specific and whole-canopy phenology remains largely uncharacterized. We present a unique analysis of historical tropical tree phenology collected in the central Congo Basin, before large-scale impacts of human-induced climate change. Ground-based long-term (1937-1956) phenological observations of 140 tropical tree species are recovered, species-specific phenological patterns analyzed and related to historical meteorological records, and scaled to characterize stand-level canopy dynamics. High phenological variability within and across species and in climate-phenology relationships is observed. The onset of leaf phenophases in deciduous species was triggered by drought and light availability for a subset of species and showed a species-specific decoupling in time along a bi-modal seasonality. The majority of the species remain evergreen, although central African forests experience relatively low rainfall. Annually a maximum of 1.5% of the canopy is in leaf senescence or leaf turnover, with overall phenological variability dominated by a few deciduous species, while substantial variability is attributed to asynchronous events of large and/or abundant trees. Our results underscore the importance of accounting for constituent signals in canopy-wide scaling and the interpretation of remotely sensed phenology signals.
Kearsley, Elizabeth ; Computational and Applied Vegetation Ecology Lab, Department of Environment, Faculty of Bioscience Engineering Ghent University Gent Belgium ; BlueGreen Labs Melsele Belgium
Verbeeck, Hans; Computational and Applied Vegetation Ecology Lab, Department of Environment, Faculty of Bioscience Engineering Ghent University Gent Belgium
Janssens, Steven B; Meise Botanic Garden Meise Belgium ; Department of Biology, Leuven Plant Institute KULeuven Leuven Belgium
Yakusu, Emmanuel Kasongo; UGent-Woodlab (Laboratory of Wood Technology), Department of Environment, Faculty of Bioscience Engineering Ghent University Gent Belgium ; Service of Wood Biology Royal Museum for Central Africa Tervuren Belgium ; Faculté de gestion des ressources naturelles renouvelables Université de Kisangani Kisangani Democratic Republic of Congo
Kosmala, Margaret; Department of Organismic and Evolutionary Biology Harvard University Cambridge Massachusetts USA ; CIBO Technologies Cambridge Massachusetts USA
De Mil, Tom ; Université de Liège - ULiège > TERRA Research Centre > Gestion des ressources forestières
Bauters, Marijn ; Isotope Bioscience Laboratory - ISOFYS, Department of Green Chemistry and Technology Ghent University Gent Belgium ; Research Group of Plants and Ecosystems (PLECO), Department of Biology University of Antwerp Wilrijk Belgium
Kitima, Elasi Ramanzani; Institut National pour l'Etude et la Recherche Agronomiques-INERA Yangambi Democratic Republic of Congo
Ndiapo, José Mbifo; Institut National pour l'Etude et la Recherche Agronomiques-INERA Yangambi Democratic Republic of Congo
Chuda, Adelard Lonema; Institut National pour l'Etude et la Recherche Agronomiques-INERA Yangambi Democratic Republic of Congo
Richardson, Andrew D ; Center for Ecosystem Science and Society Northern Arizona University Flagstaff Arizona USA ; School of Informatics, Computing and Cyber Systems Northern Arizona University Flagstaff Arizona USA
Wingate, Lisa; INRAE, UMR ISPA Villenave d'Ornon France
Ilondea, Bhély Angoboy; UGent-Woodlab (Laboratory of Wood Technology), Department of Environment, Faculty of Bioscience Engineering Ghent University Gent Belgium ; Service of Wood Biology Royal Museum for Central Africa Tervuren Belgium ; Institut National pour l'Étude et la Recherche Agronomiques Kinshasa Democratic Republic of Congo
Beeckman, Hans; Service of Wood Biology Royal Museum for Central Africa Tervuren Belgium
van den Bulcke, Jan; UGent-Woodlab (Laboratory of Wood Technology), Department of Environment, Faculty of Bioscience Engineering Ghent University Gent Belgium
Boeckx, Pascal; Isotope Bioscience Laboratory - ISOFYS, Department of Green Chemistry and Technology Ghent University Gent Belgium
Hufkens, Koen; Computational and Applied Vegetation Ecology Lab, Department of Environment, Faculty of Bioscience Engineering Ghent University Gent Belgium ; BlueGreen Labs Melsele Belgium ; INRAE, UMR ISPA Villenave d'Ornon France
BELSPO - Belgian Federal Science Policy Office UGent - Ghent University
Funding text :
Historical phenological observations and climatological measurements were made by researchers from the Institut National pour l'Étude Agronomique du Congo (INEAC) and archived by the Institut National pour l'Étude et la Recherche Agronomiques (INERA) at Yangambi. We thank Zooniverse for hosting the phenological data recovery project “JungleRhythms” and all citizen scientists for their combined efforts in transcribing data. Recent forest inventory data were obtained through the COBIMFO project funded by the Belgian Science Policy Office (Belspo; contract no. SD/AR/01A). The postdoctoral funding for EK was granted by the BOF Special Research Fund, Ghent University, Belgium. KH acknowledges funding through the Belgian Science Policy Office COBECORE project (BELSPO; grant BR/175/A3/COBECORE), the European Union Marie Skłodowska-Curie Action (project number 797668), and the NSF Macrosystems Biology program (Award Numbers EF-1065029).Historical phenological observations and climatological measurements were made by researchers from the Institut National pour l'Étude Agronomique du Congo (INEAC) and archived by the Institut National pour l'Étude et la Recherche Agronomiques (INERA) at Yangambi. We thank Zooniverse for hosting the phenological data recovery project “JungleRhythms” and all citizen scientists for their combined efforts in transcribing data. Recent forest inventory data were obtained through the COBIMFO project funded by the Belgian Science Policy Office (Belspo; contract no. SD/AR/01A). The postdoctoral funding for EK was granted by the BOF Special Research Fund, Ghent University, Belgium. KH acknowledges funding through the Belgian Science Policy Office COBECORE project (BELSPO; grant BR/175/A3/COBECORE), the European Union Marie Skłodowska‐Curie Action (project number 797668), and the NSF Macrosystems Biology program (Award Numbers EF‐1065029).
Commentary :
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