Study sites
This study was conducted in 30 permanently monitored forest sites
located in southeast Brazil (Figure 1). The largest distances among
sites are of 900 km (latitude) and 177 km (longitude). Altitudes vary
between 447 and 1490 meters above sea level, whereas mean annual
precipitation (MAP) varies between 763 and 1831 mm, and mean annual
temperature (MAT) between 17.1 and 25.4 °C. The data include three
forest types distinguished by deciduousness and climate (details in
Supplementary Material Table S1): (i) five evergreen forest sites, with
little to insignificant deciduousness and under the coldest and wettest
climate in the dataset (measured between 1995-2019); (ii) sixteen
semideciduous forest sites, with 20-50% of canopy deciduousness during
the dry season and under an intermediate climate in the dataset
(measured between 1987-2019); (iii) and nine deciduous forest sites,
with more than 50% canopy deciduousness during the dry season and under
the driest and hottest climate of our dataset (measured between
2002-2019). All sites are closed-canopy and mixed-age forests with
similar conservation statuses, with no indication of wood extraction or
fire occurrence.
Vegetation data were collected from 400 m² plots, distributed across
each site aiming to capture local heterogeneity reliably (total of 34
hectares sampled). Each site was measured at least twice, with an
inclusion criterion equal to or higher than 5 cm of quadratic mean
diameter at the reference height (1.30 m; dbh). All individuals that met
the inclusion criterion were tagged and their point of measurement (POM)
recorded. We used the POM as a reference for the subsequent
measurements. When the POM of a given stem needed to change between
measurements, we estimated stem diameter growth from the ratio between
the current and previous POMs (Talbot, et al. 2014). Tree identification
was performed by specialists in the field or by consulting herbaria.
Species names followed APG IV (Angiosperm Phylogeny Group, 2016) and
were standardised based on The Plant List (2020).
We extracted wood density values of all individuals from the global wood
density database (Chave et al., 2009; Zanne et al. 2009). When wood
density was not available at the species level, we used the average wood
density value of other species within the same genus or family. We
calculated each tree’s aboveground woody biomass (AGWB) with the
pantropical allometric equation proposed by Chave et al. (2014), with
package biomass (Réjou-Méchain, Tanguy, Piponiot, Chave, &
Hérault, 2017) in the R environment. We used the modified version of
this equation because information on tree height was unavailable. We
corrected the values of AGWB productivity with the CIC1 equation by
Talbot et al. (2014). We removed the productivity of recruited species
because individual AGWB is non-numeric. We calculated the average AGWB
(or average size) of each population based on their initial total
biomass (sum of AGWB of all individuals) divided by the total number of
individuals at the beginning of monitoring.
We considered as “locally extinct” those species which disappeared
from their original occurrence area, in one or more sites; as
“regionally extinct” those species which disappeared in all sites of
our dataset; and as “recruited” those species which were absent from
all areas in the first measurement, but met the inclusion criterion at a
certain point and remained in the dataset until the last measurement.