Study site
The Brazilian Atlantic Forest covers today only about 12% of its
original extension and is distributed in fragments (Ribeiro et
al. , 2009). Because it also presents high species richness and
endemism, the forest along the coast was classified as a hotspot for
biodiversity conservation (Myers et al. , 2000). The vegetation
closest to the beach, covering sandy soils, is called restinga .
It can vary from sparse herbaceous to forest communities (i.e.
white-sand tropical forest; Oliveira et al. , 2014). The low
altitude (< 10 m; Joly et al. , 2012) and high permeable
soil result in periodic water table flood, especially during the rainy
season. Microtopographic variation forms dry sandy cords between flood
channels, which, when dry, hold high quantities of organic matter
(Diniz, 2009). While some plant species are flood-tolerant, others are
restricted to the sandy cords (Oliveira et al. , 2014). Due to its
proximity to the beach, restinga communities are highly
threatened in Brazil by the real estate market (Alho et al. ,
2002).
In the present study, we collected data in a 1-ha, permanent plot (23°
21’ 22” S and 44° 51’ 03” W) installed at a protected restingaforest in the northern coast of the state of São Paulo, southeastern
Brazil. The restinga forest is composed of dense vegetation, but
light levels are high in the understory (Joly et al. , 2012),
resulting in developed shrub and herbaceous strata. Epiphytes and lianas
are also common (Fernandes and Queiroz, 2015). This forest was recently
formed from the downward movement of some species from the Atlantic
Forest of the interior of the state of São Paulo (Eisenlohr et
al. , 2013; Sanchez et al. , 2013).
The study plot was divided into 100 subplots of 10 m × 10 m (Jolyet al. , 2012). The regional climate is tropical humid, with mean
annual precipitation of 2634 mm and mean annual temperature around 22 ºC
(Morellato et al. , 2000). The plot presents 84 tree and palm
species, being Myrtaceae and Fabaceae the richest families, and
Myrtaceae, Arecaceae, and Euphorbiaceae the most abundant ones (Jolyet al. , 2012).