Caatinga

Caatinga is a type of vegetation, and an ecoregion characterized by this vegetation 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 between 700,000 km² and 1,000,000 km² (depending on the source), over 10% of the Brazil's territory.

Caatinga is a xeric shrubland and thorn forest, which consists primarily of small, thorny trees that shed their leaves seasonally. Cacti, thick-stemmed plants, thorny brush, and arid-adapted grasses make up the ground layer. Many annual plants grow, flower, and die during the brief rainy season.

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Caatinga covers the northeast portion of Brazil. It is located between 3°S 45°W and 17°S 35°W, extending across eight states of Brazil: Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe, Bahia, and parts of Minas Gerais. The Caatinga includes several enclaves of humid tropical forest, known as the Caatinga enclaves moist forests.

The Caatinga is bounded by the Maranhão Babaçu forests to the northwest, the Atlantic dry forests and the Cerrado savannas to the west and southwest, the humid Atlantic forests along the Atlantic coast to the east, and by the Atlantic Ocean to the north and northeast.

Caatinga is pronounced 'ca-tin-gaa'. The Caatinga is a very dry place in Brazil. Despite its semi-arid climate, it's inhabited by about 15 million people. There are little drinkable water sources and harvesting gets difficult because of the irregular pluviosity. Droughts occur frequently in Caatinga.

However, many critics have said the poor life of most inhabitants of Caatinga is more due to the lack (or insufficient existence) of public politics and irrigation projects in this region, argueeing that most of the region has agricultural or touristical potential. In fact, there are many successful agricultural lands that became productive after being irrigated, especially in the regions near to the São Francisco river valley [ [http://www.valedosaofrancisco.com.br/Economia/Potencialidades-SolosparaIrrigacao.asp Vale do São Francisco - Economia - Potencialidades - Solos para Irrigação ] ] . Irrigation policies are, however, concentrating land and water in the hands of major companies, while the small farmers who depend on agriculture for their basic subsistence are not profiting as much from it. Critics of the government's irrigation plans believe the current irrigation policies are centralizing the property of water, while endangering long-term survival by draining the existing water resources. One of the alternatives they propose is a de-centralized system of small local water cisterns and tanks to catch rain water during the rainy season and conserve it for use during the dry season. In this way, interference with the natural flow of rivers would be avoided and water would no longer be a power-factor used by politics and industry.

Climate

The 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, thus lessening 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 no leaves the Caatinga has a yellow-grey, desert-like look.

The drought usually ends in December or January, when the rainy season starts. Immediately after the first rains, the grey, desert-like landscape starts to transform and becomes completely green within a few days. Small plants start growing in the now moist soil and trees grow back their green leaves. At this time, the rivers that were mostly dry during the past 6 or 7 months, start to fill up and the streams begin to flow again.

Flora

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 tree 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.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 dependent 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. Also, plant experts have said to have found a new cacti called the Columna Chollang. The plant is said to be pink with black thorns in a small ball shape. It is found in foliage in the hotter parts of the caatinga.It has been said that, different from man, Caatinga vegetation has adapted itself completely to its conditions. While man is trying to fight against the yearly recurring system of about 5 months of rain followed by 7 months of drought, nature has learned to cohabit with it. The idea of fighting the yearly "rain-drought" system by irrigation has been compared to the idea of Scandinavans fighting the yearly snow season (in which nothing grows, just like in the Caatinga's dry season) by promoting Global Warming. Some people believe that the best solution for human life in the Caatinga should be in finding smart ways of cohabiting with the "rain-drought system" instead of fighting drought through irrigation. Caatinga vegetation's enormous creativity in finding solutions for the regular lack of water can serve as an example to man, they believe.

:"See also: "List of plants of Caatinga vegetation of Brazil

Fauna

The Caatinga is home to several endemic species of birds, including Lear's Macaw or Indigo Macaw "(Anodorhynchus leari)", Spix's Macaw or Little Blue Macaw "(Cyanopsitta spixii)", and Moustached Woodcreeper "(Xiphocolaptes falcirostris)."

People

Around 15 million people live in the Caatinga region [http://portal.mec.gov.br/setec/arquivos/pdf/07tabpnad.pdf] , and are regarded as belonging the poorest inhabitants of Brazil. 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.

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. While this is very good news for some farmers, it has also had serious consequences for people who have always depended on the natural flow of the river. Big dams have brought an end to the high tides in the rainy season, which used to spread fertile mud over the fields creating a rich ground that could be used for agriculture during the dry season. Also, salinization of the soil is becoming a threat since big parts of the land are irrigated with saline water, thus sterilizing the soil. The irrigated farms along the São Francisco River are currently exporting grapes, papayas and melons.

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 maybe unavoidable.

ee also

*Sertão

References

External links

* [http://www.worldwildlife.org/wildworld/profiles/terrestrial/nt/nt1304_full.html Caatinga (World Wildlife Fund)]
* [http://www.ibama.gov.br/ecossistemas/caatinga.htm IBAMA]
* [http://www.brazilnature.com/caatinga.html Brazil Nature]
* [http://www.agronline.com.br/artigos/artigo.php?id=81 Caatinga: Brazilian national heritage threatened]
* [http://www.birds-caatinga.com Birds of the Caatinga] The Avifauna of the Interior of Ceará, Brazil