Caatinga
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Caatinga is in the northeastern part of Brazil. The name "Caatinga" is a Tupi word meaning "white forest" or "white vegetation" (kaa = forest, vegetation, tínga = white). It covers about 700,000 km2. The Caatinga has a semi-arid climate with average annual temperatures of about 28 °C. The area has a very hot and dry winter and a hot and rainy summer. The rivers of the Caatinga only run during the rainy summers and in some places the streams are interrupted during the dry winters. The vegetation consists mainly of open shrubs that are resistant to drought.
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Location
Caatinga covers the northeast portion of Brazil. It is located between 3°S 45°W and 17°S 35°W, lying upon eight provinces of Brazil near the east coast by the Atlantic Ocean: Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagôas, Sergipe and Bahia. The caatinga is closest to the larger cities of Fortaleza, Recife and Salvador. The southern half of the caatinga is perforated with some areas of humid tropical forest.
Climate
Caatinga has only two distinguishable seasons. These are the winter, when it is very hot and dry, and the summer when it is hot and rainy. During the dry winter periods there is no foliage or undergrowth. The vegetation is very dry and the roots begin to protrude through the surface of the stony soil. They do this in order to absorb water before it is evaporated. All leaves fall off the trees to reduce transpiration in order to lessen the amount of water that is lost in the dry season. During the peak periods of drought the Caatinga's soil can reach temperatures of up to 60 °C. With all the foliage and undergrowth dead during the drought periods and all the trees having to leaves the Caatinga has a grey, desert-like look.
The drought ends at the end of the year and it begins to rain in the new year. With the coming of rain, the grey, desert-like landscape starts to transform into a much greener land. Small plants start growing in the now moist soil and trees grow back their green leaves. At this time the waters in the rivers start to fill up and the streams begin to flow again. The parts of the river that were dried out now have flowing water again.
People
People use many plant species from the Caatinga region. Palms are very important to the economy in northeast Brazil. People from this area are greatly dependant on extraction from babassu, carnaúba, tucúm and macaúba, from which lauric and oleic oils are made from. Many trees are also used for lumber in this area, including these species: Anadenanthera macrocarpa, Ziziphus joazeiro, Amburana cearensis, Astronium fraxinifolium, Astronium urundeuva, Tabebuia impetiginosa, Tabebuia caraiba and Schinopsis brasiliensis, Cedrela odorata, Dalbergia variabilis, Didymopanax morototoni and Pithecellobium polycephalum. Some plants are also used for medical purposes.
The poorest population in Brazil lives in the northeast, which also happens to be the most densely populated part of the country. Over 60 million people survive on the minimal vegetation of the Caatinga. A very large part of the population depends on agricultural or forest industries for over half of their income. Harvesting of the caraiba woodland for lumber has reduced its size. This reduction may have contributed to the endangerment of the Spix's Macaw (cyanopsitta spixii).
Agriculture
In some places the Caatinga has very fertile soils. Inhabitants plant fruits in the fertile soil to process and eat, sell and export. Some regions are being irrigated, most notably the São Francisco River. This is very good news for farmers, although salinization of the soil is becoming a threat since the land is irrigated with saline water. If there is a surplus in goods as a result of the new irrigation this area will start exporting a lot more products outside of Brazil. The São Francisco River is currently exporting grapes, papayas and melons and may become a real competitor in the world marketplace.
Having and using all these resources has some negatives. Intensive agriculture, along with excessive grazing by cattle and goats is affecting the population structure of some of the more important plant and animal species. Deforesting for industrial uses like fuel and charcoal destroys the vegetation. The combination of drought and misuse of the land are becoming a major threat. If these practices continue at the current rate, desertification is possible.
Vegetation
The Caatinga can be separated by vegetation types into eight different areas. The Caatinga forest has deciduous tropic broadleaved trees. The forest canopy covers about 60% of the ground. This type of vegetation is present in wetter areas with more rainfall. The arborescent area is an area mainly of shrubs with some trees with less than 60% coverage. Aborescent-shrubby closed Caatinga is forest with closed shrub and three coverage less than 60%. Aborescent-shrubby open Caatinga is similar but with more shrubs and cacti. In the shrubby closed Caatinga scrub is more common. The shrubby open Caatinga areas occur on shallow soils and rocky outcrops; this area contains trees, cacti and bromeliads. The Caatinga savanna is areas with some trees and some scrub. The rocky Caatinga savanna contains less than 10% coverage of tropical scrub; these plants are protruding from cracks in rocks and pavements.de:Caatinga