Forests Caatinga

Tall caatinga forest Low caatinga forest Caatinga forest Patchy scrub on sandy dunes Campo rapestre... 

Lower montane rain forest Upper montane rainforest Lower montane araucaria rain forest Upper montane araucaria rain forest Lowland seasonal semideciduous forest Submontane seasonal semideciduous forest Lower montane seasonal semideciduous forest Upper montane seasonal semideciduous forest Lowland seasonal deciduous forest Submontane seasonal deciduous forest Lower montane seasonal deciduous forest Upper montane seasonal deciduous forest Caatinga Carrasco... 

FIGURE 7.10 Venn diagrams extracted from the checklists showing the number of tree species shared by seasonal forests in different geographical regions of eastern South America (left side), and by seasonal forests, caatingas, cerrados and chaco forests (right side). 

Uhl, C, C. F, Jordan, K. Clark, H. Clark, and R. Herrera. 1982. Ecosystem recovery in Amazon caatinga forest after cutting, cutting and burning and bulldozer clearing treatments. Oikos 38 313-320. 

Klinge, H., and R. Hetreia. 1983. Phytomass structure of natural plant communities on spodosols in southern Venezuela the tall Amazon caatinga forest. Vegetatio 53 65-84. 

These species are distributed over five main types of biomas the cerrado savannahs, the Mata Atlantica rain forest, the Amazon forest, pantanal wetlands, and caatinga semiarid scrublands, as can be seen in Fig. (1). In spite of all this wealth, the first two are among the ecosystems regarded as hotspots in South America [5]. 

From the perspective of conservation, endemism may be more important than diversity (Gentry, 1995). High-diversity forests may be composed of wide-ranging species that merit less conservation focus than local endemics. From the evolutionary perspective, endemics are also interesting. Some areas of dry forest are clearly much richer in endemics than others. The Bolivian chiquitano (only three woody endemics Killeen et al.. Chapter 9) and seasonal forests of the Atlantic coastal forests of Brazil (Oliveira-Filho et al.. Chapter 7) are relatively poor in endemic species, whereas some inter-Andean valleys of Peru (Linares-Palomino, Chapter 11), Ecuador (Lewis et al. Chapter 12), Bolivia (Wood, Chapter 10), the Brazilian caatingas (Oliveira-Filho et al. Chapter 7 Queiroz, Chapter 6) and Mexican dry forests (Lott and Atkinson, Chapter 13) show higher endemism. This has considerable implications for both conservation prioritization and inference of history as discussed in the sections below. 

The cerrado as a whole is surrounded by very distinct neighbouring biomes the semi-arid caatinga (to the north-east), the wet pantanal (to the south-west), the moist and hot Amazonian forest (to the north-west) and the somewhat drier and cooler Atlantic forest (to the south-east). The cerrado flora is influenced by all these surrounding ecosystems and characteristic ecotonal vegetation occurs. Elements derived from the neighbouring biomes become non-endemic, so-called accessory species in the cerrado flora and this process has consequently produced contrasting regional variation in its flora (see Meio et al 2003 and Ratter et al Chapter 2). 

Species of the Caatinga Extending to the Atlantic Rain Forest... 

The caatinga constitutes the largest and most isolated nucleus of the SDTF. Historically, it has been considered as having a low number of species, and as poor in endemism at both the generic and the specific levels (Rizzini, 1963, 1979 Andrade-Lima, 1982). Following this view, it was proposed that the caatinga does not have an autochthonous flora, and that most of its elements were derived from the chaco and the Atlantic rain forest (Rizzini, 1963, 1979 Andrade-Lima, 1982). 

Brejo forest Dense to open, mostly shrubby caatinga... 

Studies of floristic similarity were carried out using 43 areas selected as representing the major biomes of north-eastern Brazil Atlantic rain forest (mata atldnticd), savannas cerrados), upland rocky fields compos rupestres) and caatinga. In the case of the caatinga, areas that were different based on physiognomy, type of substrate and occurrence in different geomorphological units were included (Table 6.1). An additional criterion for selection of an area was the availability of voucher specimens to check identification. In addition to the species cited in the published checklists, other... 

Tall Caatinga forest Low Caatinga forest Brejo forest... 

---