River Ecology to Be Altered by Dam

FROM deep inside a darkened tank streaked black with mildew, a sound floats upward like a soft whisper.Inside, "Qiqi," (pronounced chi-chi), the only Yangtze River dolphin in captivity, exhales through his blowhole and waves his long beak, pacing his shallow home with sonar as he has done for 11 years. To the few Chinese scientists trying to save the species from extinction, Qiqi's breath sounds more like a sigh every day. China's leadership next month will consider building a dam on the Yangtze that would hasten the steady drift of the river dolphin toward extinction. The Yangtze dolphin population has shrunk by a third since the International Union for the Conservation of Nature and Natural Resources declared it one of the world's 12 most endangered animals in 1986. Only about 200 of the silver cetaceans remain. "If we don't take further steps, the dolphin will completely die out," says Cao Wenxuan, an ichthyologist at the Institute of Hydrobiology in Wuhan. The threat to the dolphin is one example of how the world's largest dam would damage the environment in the world's most densely populated river basin. Beijing will base its decision on building the dam on two studies claiming that gains in flood control, hydropower, and shipping would far outweigh the injuries to man and the environment caused by the dam, Chinese and foreign scientists say. The studies, one conducted by China and the other by a consortium of Canadian companies in the mid-1980s, are flawed, the scientists say. According to them, the studies are too superficial to enable Beijing to make a valid environmental assessment. Critics charge that the dam would harm the environment for man, the river dolphin, and other species in several ways.

Fishing disrupted Most notably, the dam would disrupt the rhythmic rise and fall of the river, causing losses for some 75 million people who eke out a living downstream from the dam site, the scientists say. The losses to fishermen and farmers will be especially severe because China lacks the money to shepherd them into a comparable livelihood, says Joseph Larson at the University of Massachusetts, Amherst. There is "no excuse" for Beijing's failure to "factor the losses for these people into the costs of the dam," says Dr. Larson, a professor of wildlife biology and director of the university's Environment Institute. Moreover, the dam would likely curtail the river's capacity to flush out pollution and replenish nutrients downstream, observers say. The gigantic structure would probably reduce the volume and quality of water for city dwellers and peasants, and increase soil erosion and sedimentation. Finally, the dam could threaten an array of wildlife, including the Siberian crane, Chinese sturgeon, and the dolphin, according to the scientists. The possible changes to the environment would be so far-reaching and complex that they defy accurate prediction, they say. "The scale of the Three Gorges project is so vast that there is no way that anyone will be able to figure out how to classify the social and ecological impact of it," says Baruch Boxer, head of the department of human ecology at Rutgers University. The uncertainties highlight a paradox reminiscent of Frankenstein: Mankind's awesome power to control nature exceeds its ability to comprehend the myriad consequences resulting from the exercise of such power. Chinese environmentalists opposed to the dam can draw on the ancient example of the legendary hydroengineer, Yu the Great. According to legend, Yu's father, Kun, toiled for nine years to repress China's rivers with dikes and embankments. He failed and the emperor had him executed. But Yu believed man should seek harmony with nature. He assumed the imperial post of his father and spent 13 years dredging riverbeds and allowing the rivers to follow their natural course to the sea. In the view of Chinese and foreign environmentalists, China should learn from the folly of Kun's effort to conquer nature. But advocates of the dam maintain that China must place further demands on nature to meet the needs of development. "Some people like to talk about ecological problems, but the ecological system has to serve the masses," says Chen Jisheng, director of the Yangtze River Scientific Research Institute, a leading booster of the dam. The dam and reservoir at the Three Gorges would defile scenery that for centuries has inspired some of China's richest folklore and most moving poetry. From out of swirling mists, sheer cliffs of white granite fall hundreds of feet into the river, dwarfing boatmen on sampans who rhythmically lean into their oars. Lacking funding and political leverage, the successors to Yu are engaged in a rearguard effort to save the most besieged wildlife on the Yangtze from the proposed dam and more immediate menaces. For example, scientists at the Institute of Hydrobiology in Wuhan have obtained from the government only half the funding they need for modest attempts to prevent the Yangtze River dolphin from sliding into extinction. "The dolphin is much more threatened and much smarter than the panda, but we receive far too little money to protect it," says the institute's Dr. Cao. The Three Gorges dam would speed the demise of the dolphin by removing much of the silt and sand from the river's flow. The comparatively clear and swift water would erode the sandbars and spits that form the foundation of the dolphin's habitat and spawning ground for the fish that make up a dolphin's diet, Cao says. The dam would also dramatically increase shipping, already a leading killer of the dolphin on the Yangtze, he says. The institute hopes to breed river dolphins at the research base now tending Qiqi but it has received only about half the $1.1 million it needs, says Chen Peixun, a dolphin specialist at the hydrobiology institute.

Dolphin reserve planned The institute also aims to prepare a small spur of the Yangtze as a dolphin reserve. But again, the government has opened its purse only part way, providing only half the $1.9 million necessary, according to Dr. Chen. The conservationists have enough funds only to pay 15 wardens to urge ships to give way to the dolphins along a 120-mile stretch of the river near Honghu, she says. "In China we have many problems to solve and so the government can't make the dolphin the No. 1 priority," Chen says. But the government has put the dolphin and other Yangtze wildlife so low on its list of concerns that it apparently considers them expendable. "Even if the dolphin would become extinct because of the Three Gorges Dam, this would not stop the project," says Wang Jiazhu, chief engineer of the dam.