My destination was a tiny area in the midst of the Amazon basin, a few hectares of land in the middle of a preserve called the Tapajos National Forest, 67 km south of Santarem in the Brazilian state of Para. After a tooth-loosening ride along a cratered, flooded jungle road and a short but slippery hike into the 25-year-old preserve, I finally got to my goal-a surreal scene in the heart of the rain forest. As far as the eye could see, transparent plastic tents covered the forest floor, which was crisscrossed by a complicated network of trenches and pits. I lowered myself to the bottom of one of the holes and discovered that despite the intermittent downpours that sweep the region, the earth was relatively dry. The plastic tarps and the trenches were designed to carry almost all rainfall out of this patch of forest. As a result-and according to plan-the Brazil nut, tropical cedar and other great trees of the affected zone were beginning to suffer from thirst, even as rainwater doused the leafy forest canopy.
This deliberate tree murder-call it selvacide-was the very purpose of the Christo-like covering of the rain-forest floor. The eerie area was the center of a $700,000, U.S.- and Brazil-financed experiment to slowly starve a patch of rain forest of life-sustaining moisture and see what happens as a result. The seemingly sadistic effort was a controlled version of what biologists fear happens periodically all across the Amazon, the precursor of a disaster that could be only a few years, or even months, away.
The man behind the bizarre experiment is Daniel Nepstad, 42, a personable and laconic American ecologist who divides his time between the Woods Hole Research Center in Massachusetts and the Amazon Institute for Environmental Research (ipam), based in Belem, near the mouth of the Amazon. The 16th century philosopher Francis Bacon wrote that nature best reveals her secrets when tormented; Nepstad is doing just that to help save 150 million hectares-an area three times the size of France-that are in imminent danger of destruction by firestorms that would dwarf anything ever seen before. "For the first time," says Nepstad, "we can see the ingredients for the beginning of the end of the Amazon."
There is plenty of evidence to support Nepstad's concern. Almost every year, more and more of the rain forest is going up in smoke. In 1998, in the wake of the weather shifts brought on by El Niño's warming the Pacific waters off South America, some 40,000 sq. km of the Brazilian Amazon was scorched. Smoke-related ailments killed 700 people, put more than 10,000 in the hospital, according to ipam, and afflicted tens of thousands of others who did not show up in official statistics. The following year, when Brazilian President Fernando Henrique Cardoso tried to become the first chief executive in 30 years to visit the northwestern state of Acre, the forest was burning again. Cardoso was forced to cancel his trip. Now Nepstad estimates that fully one-third of the remaining dense forest in the Brazilian Amazon will be vulnerable in the near future. The deforested area could grow big enough to swallow Alaska and California combined. And soon: during the past two decades, El Niños, which set the stage for fires, seem to have become stronger, more frequent and longer lasting. If this pattern holds, the next powerful El Niño is not far in the future.
The dry soil at the bottom of the Tapajos pit is one clue to the nature of this potential catastrophe. Rain-forest trees suck moisture from as deep as 18 m beneath the fragile surface of the land. During periodic droughts, such as occurred during 1998's El Niño, vegetation can rapidly deplete this groundwater, desiccating trees and turning them into potential torches. El Niño provides the tinder, but humans provide the match. Human penetration of the Amazon, rather than lightning or other natural phenomena, sparks most of the huge fires, and that penetration is increasing, along with deforestation and slash-and-burn agriculture. Fire, deforestation and roads are linked in an unholy trinity. In 1998, Brazilian authorities found themselves battling enormous fires in the states of Para (where 40% of the southeastern forests burned), Roraima and Mato Grosso. Most blazes started near roads as settlers burned accessible forest to clear land for farms. The only reason even bigger stretches of the dense forest around Tapajos did not go up in flames is that no paved roads penetrate the most vulnerable areas. But they are coming.
Around the world, scientists have found that roads are the single best (but not infallible) predictor of tropical deforestation. In the Brazilian Amazon, roughly 75% of the deforestation that has taken place has occurred within 50 km of a paved road. In the 26 years after the 1965 paving of the slender highway between the Amazon city of Belem and Brasilia, 58% of the forests disappeared in a 100-km swath on either side of the road. The paving of 1,460 km of highway BR-364 between the city of Cuiaba in Mato Grosso and Porto Velho in Rondonia caused the disappearance of a third of the forest bordering the highway in just 15 years.
And now the highway menace is coming to this part of Para. Brazil's ministries of planning and transportation have ignored or forgotten the trauma of 1998 and, without consulting the federal Ministry of Environment, have approved paving the last dirt stretch of BR-163, which runs 1,741 km north and east from Campo Grande in Mato Grosso do Sul to the city of Santarem in Para. The 700-km unpaved section runs directly past Tapajos National Forest and on through millions of hectares of the most vulnerable parts of the rain forest. Says Nepstad: "Brazilian scientists call this area the 'corridor of drought,' and it becomes kindling when El Niño roars through."
The unpaved stretch takes six days to drive in the rainy season. It would require less than a day on an all-weather surface. The decision to pave the highway is largely the product of vigorous lobbying by giant agribusinesses, which see the route as a more profitable way to export soybeans. (After the U.S., Brazil is the world's largest exporter of the crop.) A Brazilian-American consortium is planning to build an enormous dock-and-loading system in Santarem, the sleepy port that lies at the junction of the Tapajos and Amazon rivers, 700 km from the Atlantic Ocean. Exporting through Santarem might save agribusinesses $1 per 30-kg bag of soybeans.
Nepstad argues that the costs to the forest will far offset those gains. More settlers will flood in, and fires will follow the settlers. Moreover, fire begets fire in the Amazon. Dead trees provide the fuel for successive burnings, and cleared areas are often 12C hotter than the rain-forest floor, which has a leafy canopy that blocks and absorbs as much as 99% of incoming sunlight.
Indeed, if paving BR-163 goes ahead, the soybean exporters could become victims of their development plans by helping produce a drought. Through evaporation, the forest recycles 7 trillion tons of water annually from the ground back into the atmosphere-as much as 50% of all the moisture it receives from rainfall. A good portion of that water vapor is carried by air currents that bounce off the Andes and head southward to drop rain on farming regions in the southern states of Mato Grosso and Goias, both part of Brazil's breadbasket. In other words, no Amazon forest in Brazil's north, no rain in the south. The possibility of calamity threatens far more than isolated trees.
Scientists have long studied the horrendous impact that fire has on the rain forest. Alberto Setzer of the Brazilian space agency, inpe, shocked the world when he used satellite imagery to show the extent of the burning in 1988. Out-of-control burning first brought me to Brazil in 1989 when I wrote the cover story for the Sept. 18 issue of Time called "Torching the Amazon." I have made several trips to parts of this giant ecosystem in neighboring countries since then, but this was my first trip back to the Brazilian Amazon, and there was, amid the rising cause for concern, some good news to report.
A decade ago, for instance, few people would have predicted that in the year 2000, the huge state of Amazonas, next door to Para, would be the least deforested region in the ecosystem-especially since in earlier administrations the Governor, Amazonino Mendes, had offered to hand out chain saws to anyone wanting one, in order to spur land clearing. (In recent years, Mendes has adopted a slightly softer approach toward the forest.) Manaus, the capital of Amazonas, has grown rapidly in wealth and size in the past 10 years, but without massive tree cutting in surrounding areas. Local soils are notoriously bad, for one thing, which discourages agriculture, and besides, most immigrants can make more money in town.
There has also been a remarkable turnaround in Brazilian public opinion about the rain forest. In 1989, then President Jose Sarney was defensive and defiant about criticism of Brazil's failure to protect the Amazon; last June, by contrast, an outpouring of popular protest forced the Brazilian Congress to drop a plan to reduce from 80% to 50% the amount of forest to be set aside as nature preserves in future Amazonian development projects. Among the most vocal opponents of the rollback was Jose Sarney Filho, the federal Environment Minister and son of the pro-development former President. In Acre, the frontier state where environmental martyr Chico Mendes was assassinated in 1988 by ranchers angered by his efforts to halt deforestation, change is more drastic. The current Governor, Jorge Viana, was elected in 1988 in an explicitly environmentalist campaign. He has since shelved plans from the previous administration to pave 2,000 km of roads in the state. (Viana was chosen by Time in 1999 as one of its regional Leaders for the New Millennium.)
But some nightmares threatening the rain forest have grown worse. While Brazil's Congress has eliminated some subsidies that promoted indiscriminate cattle ranching and forest clearing and passed laws prohibiting new settlements in virgin forests, it has turned a blind eye to other forms of destruction. Politicians have encouraged some of the 10 million landless poor to migrate into the interior, torching forest as they go. Settlers persist in using fire to clear land for their subsistence farms because it is cheap and easy.