**3.1 Dense Rainforest**

112 The Dynamical Processes of Biodiversity – Case Studies of Evolution and Spatial Distribution

Adapted from: MMA (2011) and Roderjan et al. (2002).

Brazil. Numbers are related to sites presented in Table 1.

Fig. 1. Location of the 58 sites in the Atlantic Forest types in the state of Paraná, Southern

The Dense Rainforest, or Atlantic Forest *sensu stricto* (Oliveira-Filho & Fontes, 2000), is characterized by the dominance of large trees (25-30 m height) associated with many other biological forms, mainly epiphytes and woody lianas, that gives it its tropical appearance (Klein, 1979). Evergreen trees dominate the dense canopy (Veloso et al., 1991; IBGE, 1992).

Different plant communities of this forest type are found from the beach ridges near the Atlantic Ocean to the upper montane ridges of the Serra do Mar (Sea Mountain Range) and its western slopes towards the ecotone with Araucaria Rainforest (Figure 1). The altitudinal gradient ranges from 1 to 1887 m a.s.l., resulting in this region in a decrease of 0.54 °C for every 100 m increase in altitude (Roderjan & Grodski, 1999). While the coastal plain formations are in soils derived from Cenozoic (mainly Quaternary) marine sediments, alkali granites, embedded in high-grade metamorphic terrains, form the mineral soil horizons of the upper portions of the landscape. According to Mineropar (2001), intrusive igneous rocks from Serra do Mar were originated nearly 550 million years ago in the Upper Proterozoic to Cambrian. Faults from the Brasiliano (or Pan African) Cycle (events of the end of the late Proterozoic) and the Ponta Grossa Arch, cut the landscape in the NE-SW and NW-SE axes, respectively. Therefore, the soils of the Dense Rainforest have a high variety in parent material, genesis, depth, horizons, layers, structure, texture and organic matter.

The climate of the lower portions of the Dense Rainforest gradient, up to the transition between the Submontane and Montane formations, 600 - 800 m a.s.l. (Blum, 2010), can be classified as Cfa, or meso-thermic, according to the Köppen classification system. Daily mean annual temperature is 21 ºC, the mean temperature in the coldest month is about 16 ºC and, in the warmest month is higher than 22 ºC, with hot and wet summers (December-March), and a no-pronounced dry season. Maack (2002) considered the region as having a transitional tropical climate (Af). The climate of upper portions, above 700 m a.s.l., is classified as Cfb (humid subtropical, meso-thermic, with cool summers, frequent frosts and no pronounced dry season). The mean temperature of the coldest month (July) in the region is less than 16 ºC (reaching 12.5 ºC) and of the warmest month (February) is less than 22 ºC (20.5 ºC). Measurements in the coastal region exceed 2000 mm of rain per year, and on the slopes of the mountains these values reach 3500 mm of rain per year (Caviglione et al., 2000; Maack, 2002).

As a result of the high environmental variety the Dense Rainforest is the most heterogeneous, complex and rich forest ecosystem of Southern Brazil (Leite & Klein, 1990).

A compiled list of the tree flora of the Dense Rainforest of Southern Brazil, using data of the botanical collection of the Barbosa Rodrigues Herbaria, revealed 708 species. More than 50% of those species occur exclusively in this type of Atlantic Forest (Leite & Klein, 1990).

Dense Rainforest communities in the advanced stages of succession cover an area of 3937.5 km2 or 51,5% of the original distribution area as interpreted from satellite images from 1999 (Pires et al., 2005).

Forward we present the five cattegories of the Atlantic Rainforest.
