BRASILIA A number of animal and plant species in Brazil could die out as rising world temperatures cause more droughts, disease and rainstorms in areas like the Pantanal wetlands and Amazon rainforest, according to studies released on Tuesday.
"All our efforts to protect our biodiversity could be lost," Environment Minister Marina Silva said at an event to publicize the new research coordinated by the ministry and carried out by university, private and government scientists.
Brazil is believed to be home to roughly a fifth of all plant and animal species and the government has invested $142 million (300 million reais) since 2003 to preserve vast swathes of land in areas like the Amazon, Environmental Secretary Joao Capobianco said.
But rising global temperatures could undermine conservation efforts.
The broadest study, conducted by Brazilian space agency INPE, found that temperatures in the Amazon -- the world's largest remaining tropical rainforest -- could rise as much 8 degrees Celsius (14 F) this century.
Other studies predicted fish species could die out if rising ocean levels flood southern islands and estuaries with salt water. Further inland, the Pantanal wetlands could dry up and turn to savannah as hotter temperatures affect rains.
Prime agricultural areas in southern and southeastern Brazil are already suffering more intense downpours after temperatures rose almost 1 degree Celsius (2 F) in the last century, the INPE study said.
Extreme weather events could increase in general, INPE said, citing the example of Hurricane Catarina. Catarina became the first hurricane to form off Brazil's coast in at least half a century -- more than a year before Katrina flooded the U.S. city of New Orleans.
Brazil's human population could also suffer if warmer weather accelerates mosquito breeding cycles, increasing the chances of disease outbreaks like malaria and dengue.
And while the south could be pounded by heavier rains, drier weather is likely to hit sensitive northern areas like the humid Amazon and the already drought-stricken northeast.
This month, global climatologists released their latest report predicting average world temperatures could rise several degrees this century as heat-trapping carbon gases from burning fossil fuels clog the atmosphere.
Brazil emits less carbon gas than most countries its size partly because of its rainforest cover and partly because nearly half its passenger car fleet runs on sugar-cane ethanol.
President Bush will visit Brazil next week to discuss ethanol cooperation among other matters.
Bush is encouraging ethanol use to reduce U.S. dependency on oil and to lower its carbon emissions. The United States is the world's single largest producer of atmospheric carbon gas, and Bush was widely criticized for refusing to sign the global Kyoto protocol to cut emissions in 2001.
"I haven't spoken to President Lula, but all of humanity needs President Bush to show more commitment to reducing greenhouse gases," Silva said.
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