By Mario Osava
MANAOS, Brazil, Apr 18 1998 (IPS)

Brazil’s Amazon region is facing an immediate threat of fires, worse than those that ravaged forests earlier this yerar, as a result of the weakening of forests produced by the El Nino weather phenomenon.

Amazon forests also have been weakened by the less visible but equally destructive fragmentation of forest ecosystems, environmentalists warn.

Forest fires, that affected the northern state of Roraima between January and March of this year, served as a warning for a potentially greater catastrophe that could hit this June in the southern and eastern portions of the worlds largest forest reserve, they added.

The use of controlled burnings to clear lands for agriculture are a traditional practice on Brazil’s agricultural frontier which is fast encroaching on forest lands in the states of Para, Maranhao, Mato Groso, Rondonia and Acre – that comprise the so-called arc of deforestation. These take place every year primarily between June and September, the driest months of the year.

But forecasts for 1998 are alarming because the El Nino phenomenon has gone on for more than 12 months, and has been more intense this year. The umidity in the region decreased, with less rain and the growth of drier vegetation, easily combustible in the burn-offs, which thusd could turn into uncontrollable fires, like those in Roraima.

Several sources have emitted warnings – from United Nations agencies and the World Bank to the Institute for Research and Analysis of Amazonia, a Brazilian non-governmental organization that works in the region.

The Brazilian government recognized the risk and decided to take action against this possible catastrophe, after receiving harsh criticisms for its inaction in Roraima. Some 13 million dollars have been appropriated for the training of 100 community fire- fighting brigades, prevention systems and supervision, greater monitoring and envir onmental education campaigns.

In Roraima the fires covered 3.3 million hectares, most of which were savanna, grasslands and agricultural areas, according to the National Institute for Amazonian Research (INPA). Almost one third of the land affected, 925,470 hectares, were forests. The area now threatened in the south and east of Amazonia is much larger. It comprises five states which have greater demographic pressures, from both logging companies and expanding agriculture.

Beyond the more visible deforestation on its borders, Amazonian forests also under attack that could affect the heart of the ecosystem. The fragmentation produced by highways, logging and small deforested areas have a larger impact that is not immediately visible.

The Biological Dynamics of Forest Fragments Project, developed through an agreement between INPA and the Smithsonian Institute of the United States, has been investigating the loss of biomass that results from human alterations in the heart of Amazonia for the past 18 years.

One of the results of the project has been to confirm the existence of the edge effect, which show the ways in which the effects of deforestation, however small, penetrate the forest as a result of changes in the availability of light, wind and humidity.

Fragmentation, moreover, exacerbates the effects of droughts, like that produce d by El Nino this past year, given that even during normal years, fragmented fo rests suffer greater tree mortality, according to U.S. biologist William Laurence, coordinator of some of the research projects in the region.

Fragmentation is the most alarming risk factor for the forests because its exte nds throughout Amazonia, warned Laurance. He also fear that government plans to pave the highway between Manaos and Porto Velho,900 kilometers to the south, will lead to deforestation and fires like those seen in Roraima and to the north of Manaos.

Manaos, the capital of the state of Amazonas, in the center of the region, was covered by smoke last year for the first time, as were the areas of the agricul tural frontier to the south and east of the region. END/IPS/tra-esp/mo/mg/98) = 04162026 ORP118

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