COLUMN ONE : Plunder of Earth Began With Man : Exploding myths of a pre-industrial paradise, researchers say even the oldest civilizations have pillaged the Earth. They urge us to learn from the mistakes of Easter Islanders and the Maya.

When Dutch explorers landed on Easter Island in 1722, there was not a single tree.

Most ecologists assumed that the isolated Pacific island, now known as Rapa Nui, had always been barren. Recent studies, however, reveal that it once was covered with lush forests that were slashed and burned when humans moved there about AD 500.

The rape of Rapa Nui, archeologists are now discovering, is not unique. Whereas environmentalists and historians once believed that early humans lived in harmony with their environment, growing evidence reveals that people have plundered the Earth wherever and whenever they have lived.

From the first civilizations along the Tigris and Euphrates rivers--in what is now Iraq--to the Mayan empire of Central America, experts are beginning to agree, people have pillaged natural resources, denuded forests and sterilized fields with unwanted salt. Environmental devastation, it would seem, has been an almost inevitable companion of civilization.

And today, as society faces environmental problems ranging from deforestation and loss of biodiversity to salinization of farmland, many archeologists believe society can profit by studying where these civilizations went wrong. “We can look to the past to see the future,” said Charles L. Redman of Arizona State University.

This new environmental awakening is bringing archeologists such as Redman down from their ivory towers, where they have chronicled early humans, and thrusting them into the hurly-burly of activism and ecological prophecy.

“The hallmark focus of this generation is a redefining of archeology” from a rather abstract pursuit to one that has direct impact on day-to-day concerns, Redman said.

“We have to make the point that archeology is more than just an indulgence of a rich society,” said Don S. Rice of Southern Illinois University. “We really do have something to say to future generations.”

One impetus for the new approach is the deforestation of Central and South America and the accompanying loss of biodiversity--a broad and complex abundance of species in such wilderness areas. Ecologists argue that biodiversity must be maintained because it provides a potential source of drugs, foods and other products that will be invaluable to future generations.

In planning biological preserves, Rice argues, archeological data is crucial to demonstrating how many people regions could support in the past and what the outcomes were. “It’s hard to do this with short-term data,” he said. “It’s a little easier with a millennium of data from archeology.”

Another important issue facing the United States and other nations is the degradation of soil quality, which ultimately threatens a society’s ability to feed itself. Many earlier societies collapsed simply because of erosion.

Emerging recognition of the unintentional destructiveness of past civilizations is blasting apart “the escapist idea of the primordial paradise,” that pre-industrial societies were composed of great environmentalists who lived in harmony with their surroundings, Redman said.

One key to destroying these myths is the relatively new science of paleolimnology, the study of lake sediment. As silt from rivers and streams collects in lake bottoms, it carries pollen, ashes, eroded soil and other characteristic markers that provide a time-ordered history of a region.

By studying pollen in sediment dating from a particular period, for example, researchers can tell what types of vegetation grew naturally and what was raised by farmers. The disappearance of tree pollen is a strong indicator of deforestation. Another is the supplanting of wood ash by ash from animal dung, which is commonly burned when wood is unavailable. Large quantities of ash from the burning of buildings is a marker for warfare or environmental catastrophe, such as volcanic eruptions.

These kinds of studies “have revolutionized our understanding of the past,” said Patrick V. Kirch of UC Berkeley.

Kirch and colleague David W. Steadman have developed a 3,500-year chronology from a crater lake on Rapa Nui, which is about 1,400 miles from the nearest land and is famous for its large stone heads. Before Polynesians settled there, the pollen record shows, Rapa Nui had “radically different vegetation,” including lush forests and broad savannas, Kirch said.

Within 700 years, he said, the population of the minuscule island had grown to 10,000 and the landscape was “virtually treeless.” Traditional archeological techniques, including fossil excavation, showed that many animals had been killed off as “a direct result of human actions, “ he said. Among 30 species of sea birds, they found, only eight survived, while none of six types of land birds survived.

Artifacts excavated from dwellings show that as resources dwindled, the islanders fell into brutal warfare fighting for what little was left, until eventually there was little of anything for anybody. In sediments, thick deposits of ash from burned buildings and fields also suggest widespread warfare. Kirch found the same pattern on islands throughout Polynesia.

“We need to (free) ourselves of the old assumptions that early societies had little impact on their environment,” he said. “And the most critical message is the inevitable effects of population increase.”

A world away, in the gray North Atlantic, the Norse colonized their offshore islands around AD 800 in a pattern that Thomas Amorosi of the City University of New York calls “rape, ruin and starve.” They overpopulated the islands, overgrazed the fields and introduced agricultural practices that promoted soil erosion.

Recent silt studies have shown that food production was down, erosion had reached disastrous levels and the Norse were barely clinging to the islands when the Little Ice Age struck in the 1370s; it proved to be their death knell. Norse populations of Greenland and Vinland died out by 1500 and Iceland’s fell dramatically. Only the indigenous Inuit tribes, who adapted their lifestyles to hunting and fishing in the colder climate, persisted.

The destruction of earlier civilizations as a result of poor farming practices provides a strong argument for changes in current soil-management policies, Amorosi said. Erosion is a growing problem in the U.S. Midwest, Redman noted, with large quantities of fertile soil being washed downstream to the Mississippi Delta.

One of the chief lessons to be learned from early societies, Redman noted, is that farmland deteriorated when agriculture was centrally controlled by the government--as is the case today in Russia, China and some developing countries--rather than by local farmers who knew how to maintain soil quality.

Soil salinization caused by extensive irrigation also played a major role in the downfall of several societies, beginning with one of the earliest, Mesopotamia in the Middle East. Salinization is caused by the accumulation of mineral salts when irrigation water evaporates. As the concentration of the toxic salts increases, farming becomes more difficult.

By 2000 BC, the Ur III dynasty was flourishing in the southern half of Mesopotamia, which comprised cities with tens of thousands of inhabitants. The society invented laws, developed writing and nourished itself with wheat and other winter-cultivated cereals, and sheepherding.

As the soil became more saline, recent sediment studies have shown, agriculture shifted from wheat to the more salt-tolerant barley; by 1700 BC, “there was no more barley,” Redman said. The society became dependent on imported grains before collapsing under the burden of overpopulation. One of the last written records from Ur, Redman said, is a plaintive message from the king to one of his functionaries in the hinterlands: “Where is my shipment of grain?”

“These were a gifted, intelligent people, the pinnacle of the past,” Redman said. “If they couldn’t handle their interactions with their environment, that is a serious condemnation of human organization.” Even today, the Mesopotamian lands lie fallow, choked by plant-killing salt.

Salinization and deforestation--as well as over-hunting--were villains in the U.S. Southwest as well. When people first arrived in North America around 12,000 BC, the Southwest was like the Serengeti plain of Africa, said Redman, teeming with a bewildering variety of large animals--the so-called mega-fauna, which included saber-toothed tigers, woolly mammoths and monstrous bears three times the size of those today.

But by 10,000 BC, as scientists discovered long ago, the bulk of those animals were extinct, leaving behind only buffalo, elk and other modern species.

Salinization spelled the doom of the Hohokam, who lived in central Arizona, in the area centered on present-day Phoenix, from the time of Christ until about 1400. Conventional studies have recently shown that the Hohokam constructed elaborate irrigation canal systems, according to Glen Rice of Arizona State University. Their civilization collapsed, like that in Mesopotamia, when the soil became too salty to support agriculture--a condition that persists today.

“This sounds painfully like what is going on today in California and many other farming regions around the world,” Don Rice said. Salinization can be countered by reducing irrigation and by growing crops that require less water. Such changes are not being made, he said, because short-term profits still outweigh long-term environmental consequences.

North of Phoenix, the Chaco Canyon area was magnificently forested in the pre-industrial era. The Anasazi built five-story buildings with 40-foot rooms spanned by timbers from huge trees. “But there is not a tall tree in the area today,” Redman said.

As population and wealth grew, so did demands on the local forest for firewood and building materials, he said. And as the trees and their extensive root systems disappeared, the thin soil eroded quickly, sediment studies show.

“This was a really complex society that is simply gone,” he said. “This is not a matter of a great drought or some other external force. The society fell of its own internal weight from systematic deforestation.”

Perhaps the greatest romance has surrounded the Central American societies of the Aztecs, Teotihuacan and Maya--complex societies that created their own written language, built massive temples and architecturally sophisticated cities, perfected intensive agriculture and developed astronomy. They flourished for more than a millennium until, one by one, they mysteriously collapsed, with the Maya being the last to fall, around AD 900.

A team headed by Sarah L. O’Hara of the University of Sheffield in England studied more than 4,000 years of sediment cores from Lake Patzcuaro, west of Mexico City, and found three distinct periods of erosion. A minor episode occurred 3,900 to 3,250 years ago, when the site was first occupied. More serious erosion occurred from about 2600 to 1350 years ago, when classical civilizations thrived in the region.

But by far the most destructive era was from about 1200 to the arrival of the Spanish in the 16th Century, a period when the region was occupied by a people known as the Purepecha. O’Hara’s team reported last year that the erosion totaled as much as 85 tons of soil per acre per year, an amount she called “staggeringly high.”

The demise of the Maya, who once dominated large regions of what are now Mexico, Guatemala and El Salvador, has been particularly intriguing. A variety of recent evidence suggests that internal warfare played a major role in the collapse, but many researchers believe that environmental problems were at the root of that warfare.

Recent studies by Don Rice have shown that the Maya had destroyed more than 80% of the region’s forests by the time of their demise in the 1600s. Loss of forest, in turn, speeded erosion, slashing farming productivity and reducing the ability of individual city-states to be self-sufficient. By the time the Spanish invaded, the Maya had lost 75% of their population.

The remaining people were slaughtered by the Spanish or succumbed to disease inadvertently introduced by the invaders. Ironically, the Spanish conquest proved to be a remarkable stimulus to the environment.

Freed from the burdens of overpopulation, vegetation exploded, producing rain forests that had not existed during the time of the Maya. Only recently, Don Rice said, have researchers recognized that these forests are a new phenomenon.

But the picture painted by archeologists is not entirely gloomy. “The upside is that many societies, like the Maya, were around for a very long time,” Redman said. “Some did strikingly well for hundreds of years. We need to learn from them.

“But, more important, we need to find out why people have repeatedly adopted short-term strategies with dire long-term consequences.”