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Forest fragmentation impacts the seasonality of Amazonian evergreen canopies.

ABSTRACT: Predictions of the magnitude and timing of leaf phenology in Amazonian forests remain highly controversial. Here, we use terrestrial LiDAR surveys every two weeks spanning wet and dry seasons in Central Amazonia to show that plant phenology varies strongly across vertical strata in old-growth forests, but is sensitive to disturbances arising from forest fragmentation. In combination with continuous microclimate measurements, we find that when maximum daily temperatures reached 35 °C in the latter part of the dry season, the upper canopy of large trees in undisturbed forests lost plant material. In contrast, the understory greened up with increased light availability driven by the upper canopy loss, alongside increases in solar radiation, even during periods of drier soil and atmospheric conditions. However, persistently high temperatures in forest edges exacerbated the upper canopy losses of large trees throughout the dry season, whereas the understory in these light-rich environments was less dependent on the altered upper canopy structure. Our findings reveal a strong influence of edge effects on phenological controls in wet forests of Central Amazonia.

SUBMITTER: Nunes MH

PROVIDER: S-EPMC8854568 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Forest fragmentation impacts the seasonality of Amazonian evergreen canopies.

Nunes Matheus Henrique MH Camargo José Luís Campana JLC Vincent Grégoire G Calders Kim K Oliveira Rafael S RS Huete Alfredo A Mendes de Moura Yhasmin Y Nelson Bruce B Smith Marielle N MN Stark Scott C SC Maeda Eduardo Eiji EE

Nature communications 20220217 1

Predictions of the magnitude and timing of leaf phenology in Amazonian forests remain highly controversial. Here, we use terrestrial LiDAR surveys every two weeks spanning wet and dry seasons in Central Amazonia to show that plant phenology varies strongly across vertical strata in old-growth forests, but is sensitive to disturbances arising from forest fragmentation. In combination with continuous microclimate measurements, we find that when maximum daily temperatures reached 35 °C in the latte ...[more]

PMID: 35177619

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Dataset Information

Forest fragmentation impacts the seasonality of Amazonian evergreen canopies.

Publications

Forest fragmentation impacts the seasonality of Amazonian evergreen canopies.

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