Included here is the area based on Brazil’s Provinca de la Caatinga and includes the highlands of northeastern Brazil. It extends from Turiacu south to the southern boundary of the state of Espirito Santo. Caatinga is a term that was used by indigenous people to describe open forest or white forest. Several different types are recognised.

Caatinga Tall Forest

These tall, dry, largely draught deciduous forests can reach heights of up to 30 m and have a least three distinct strata. They are mainly associated with eutrophic soils derived from basic rocks. Common tree species include Astronium urendeuva, Cavanillesia arborea, Pterogyne nitens, Schinopsis brasiliensis, Tabebuia avellandae and the endemic Cereus jamacuru (Cactaceae). Cavanillesia arborea with its huge bloated trunk is a conspicuous species that has a distribution extending in to Western Amazonia. Other characteristic species that may be encountered include Anadenanthera macrocarpa and the endemic Aspidosperma pyrifolium (Apocynaceae) and Bursera leptophloeos (Burseraceae).

Caatinga Medium to Low Forest of Crystalline Rocks

These forests show considerable variation and can be divided in to several community types. The trees rarely exceed about 15 m in height and commonly include Astronium urundeuva and Schinopsis brasiliensis. Smaller trees typically comprise Caesalpinia bracteosa and the endemic Caesalpinia pyramidalis (Fabaceae). Other relatively common species are Amburana cearensis, Anadenanthera macrocarpa, Cnidoscalus phyllacanthus and Piptadenia zehntneri. Among the endemic species are Aspidosperma pyrifolium (Apocynaceae) found in the hotter less humid areas; Spondias tuberosa (Anacardiaceae) found on lighter soils with good drainage, and Ziziphus joazeira (Rhamnaceae) found in some of the wetter areas. Cacti are also a fairly important but have scattered distributions. Typical species include the endemic Cereus jamacaru and Opuntia palmadora (Cactaceae). At ground level the vegetation is very sparse and virtually devoid of grasses. The main under shrubs and herbs include species of Bromelia, Cassa, Melochia, Portulaca and Sida. In places the endemic Auxemma oncocalyx (Boraginaceae) is one of the dominant species especially in the State of Rio Grande de Norte and Ceará.

Caatinga Low Forest of Sandstone

This distinctive form of Caatinga is confined to highly permeable sandy soils derived from sandstone, which severely limits the amount of water available. Some of the most characteristic trees include Acacia bahiensis, Anadenanthera macrocarpa, Piptadenia obliqua, Poeppigia procera and the endemic Bursera leptophloeos (Burseraceae) and Dalbergia cearensis (Fabaceae). These range in height from 5-7 m but often emerging above the canopy are the distinctive blackish branches of Pilosocereus piauhiensis. Characteristic shrubs include Cassia acuruensis, Mimosa verrucosa, Pilosocereus tuberculatus and the endemic Cratylia mollis (Fabaceae) and Waltheria ferruginea (Sterculiaceae). The ground layer is typically poor in both herbs and grasses but of interest is the endemic Hohenbergia caatingae (Bromeliaceae). It has an adaptation for storing water in its leaf-base, which provides a convenient water supply for the local fauna.

References

Andrade-Lima, D. de. 1981. The caatinga dominium. Revista Brasileira De Botanica, 4: 149-153.

Andrade-Lima, D. de. 1982. Present-day forest refuges in northeastern Brazil. In: Biological Diversity in the Tropics. Ed. G. T. Prance. Columbia University Press.

Anon. 1996. Habitats of South America. Institute of Terrestrial Ecology and Intitut Royal Des Sciences Naturelles De Belgique.

Bucher, E. H. 1982. Chaca and Caatinga - South American Arid Savannas, Woodlands and THickets. In: Ecology of Tropical Savannas. Eds. B. J. Huntley & B. H. Walker. Springer-Verlag.

Daly, D. C. & Mitchell, J. D. 2000. Lowland vegetation of tropical South America – an overview. In: Imperfect Balance: Landscape Transformations in the pre-Columbian Amercas. Ed. D. Lentz. Columbia University Press, New York.

Leal, I. R., Da Silva, J. M. C., Tabarelli, M. & Lacher, T. E. 2005. Changing the course of biodiversity conservation in the Caatinga of northeastern Brazil. Conservation Biology, 19: 701-706.

Paganucci de Queiroz, L. 2006. The Brazilian Caatinga: Phytogeographical Patterns Inferred from the Data of the Leguminosae. In: Neotropical Savannas and Seasonally Dry Forests. Plant Diversity, Biogeography, and Conservation. Eds. R. T. Pennington, G. P. Lewis and J. A. Ratter. Taylor & Francis.

Reis, A. M. S., Araújo, E. L., Ferraz, E. M. N. & Moura, A. N. 2006. Inter-annual variations in the floristic and population structure of an herbaceous community of “caatinga” vegetation in Pernambuco, Brazil. Revista Brasileira De Botanica, 29: 497-508.

Sampaio, E. V. S. B. 1995. Overview of the Brazilian caatinga. In: Seasonally Dry Tropical Forests. Eds S. H. Bullock, H. A. Mooney & E. Medina. Cambridge University Press.