TY - JOUR

T1 - Forest fragmentation impacts the seasonality of Amazonian evergreen canopies

AU - Nunes, Matheus Henrique

AU - Camargo, José Luis C.

AU - Vincent, Gregoire

AU - Calders, Kim

AU - Oliveira, Rafael S.

AU - Huete, Alfredo

AU - de Moura, Yhasmin Mendes

AU - Nelson, Bruce

AU - Smith, Marielle

AU - Stark, Scott C.

AU - Maeda, Eduardo Eiji

PY - 2022/2/17

Y1 - 2022/2/17

N2 - 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.

AB - 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.

KW - Ecological modelling

KW - Ecosystem ecology

KW - Phenology

KW - Tropical ecology

U2 - 10.1038/s41467-022-28490-7

DO - 10.1038/s41467-022-28490-7

M3 - Article

C2 - 35177619

VL - 13

JO - Nature Communications

JF - Nature Communications

SN - 2041-1723

IS - 1

M1 - 917

ER -