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Threatened ecosystems: Brazilian Cerradohttp://www.biodiversityhotspots.org/xp/Hotspots/cerrado/
The Cerrado spreads across 1,783,200 km² of the central Brazil plateau, in the southeastern part of the country. The second largest of Brazil's major biomes, after Amazonia, the hotspot accounts for a full 21 percent of the country's land area. With a pronounced dry season, it supports a unique array of drought- and fire-adapted plant species. Jaguar, giant anteater, giant armadillo, and maned wolf are still found in the Cerrado but are competing with the expansion of Brazil's agricultural frontier.
EcosystemThe most extensive woodland/savanna region in South America, the Cerrado is also the only hotspot that consists largely of savanna, woodland/savanna and dry forest ecosystems. Within the region, there is a mosaic of different vegetation types, including tree and scrub savanna, grassland with scattered trees, and occasional patches of a dry, closed canopy forest called the Cerradão. Gallery forests are found throughout the region, although they are technically not considered part of the typical Cerrado formations.
Despite the grassy, scrub-like vegetation, the hotspot actually receives abundant rainfall, although almost all of this rain falls between October and April. The rest of the year is characterized by a pronounced dry season, and many plant species in the hotspot are well adapted to drought conditions as a result. Much of the vegetation is also adapted to fire, which is an important part of the ecology of the Cerrado. Adaptation to fire maintains a balance between grasses and woody vegetation and assists in nutrient recycling and germination. It is estimated that about 356,634 km² , or 20 percent of the original vegetation, remains intact today.
Soya boom threat to South America
The spiralling foreign demand for soya beans could mean the loss of millions of hectares of forest and savannah in South America, conservationists warn.
WWF, the global conservation group, says nearly 22 million hectares (54m acres) could be destroyed by 2020. But WWF says much of this land could be spared if soya farmers could agree to share their land with cattle ranchers. It says the demand for soya exports, used mainly in animal feed, is expected to more than double within 20 years. Gone beyond recall A WWF report, Managing The Soy Boom: Two Scenarios Of Soy Production Expansion In South America, says the area cultivated for soya in countries like Argentina, Bolivia, Brazil, and Paraguay has more than doubled since 1994. It says soya plantations contributed to the near disappearance of the Atlantic Forest in southern Brazil and eastern Paraguay.
The report says millions of hectares of Argentine's Chaco and Brazil's Cerrado - the world's most diverse savannah, home to animals found only in South America, like the anteater, jaguar and maned wolf - have also been converted into soya plantations. Onwards and upwards WWF says demand from the European Union and China for soya beans to feed cattle, pigs and chickens is stimulating the export trade. The demand, it believes, is expected to increase by 60% in the next 20 years, imperilling a further 16m ha (40m acres) of savannah and 6m ha (15m acres) of tropical forests in the region.
But WWF says this could be reduced to an estimated 3.7m ha (9m acres) if soya producers leased pasture land from cattle ranchers and integrated their crops with cattle ranching in rotation. Squaring the circle It says field tests it has funded have shown rotation means improved soils, higher yields and increased stock density. "The study shows that it is possible to achieve higher production of soya without destroying nature," said Matthias Diemer, head of WWF's Forest Conversion Initiative.
"The development of more intensive and efficient land use along existing roads and near important population centres will reduce the need to clear virgin habitats."
But for this to work, WWF says, soya producers, investors, buyers, and regulators will have to support more sustainable practices, including encouraging the effective enforcement of environmental and land use regulations. It says it is also urgent to adopt sourcing criteria and develop producer guidelines. In Switzerland the Coop supermarket chain and WWF are now establishing criteria for sustainable soya bean production. Matthias Diemer said: "WWF will look for other companies to follow. As soya is one of the most sought-after crops in the world, it is crucial that consumers can eventually buy a product that does not contribute to the destruction of South America's natural wealth." |