In Washington's Chinatown, the ancient lilting melody of "Fishing Boats Singing in the Night" fuses incongruously with the drone of diesel construction trucks hauling still more earth from the site of the city's new convention center just a block away.

A wizened old man in slacks, a short-brimmed sailor's cap and a black quilted vest moves in a half-step shuffle toward his $40-a-month room above the Wah Shing Social Club building at Eighth and H Streets NW. His eyes are dim, but Henry Ng, 82, clearly sees the changes that threaten him and Washington's fragile Chinese community.

Chinatown, a pocket of turn-of-the-century row houses and shops bounded by Fifth, Ninth, G and I streets, sits in the path of the city's grand redevelopment plans -- the convention center to the west, proposals for new hotel and department store complexes to the north and south, existing government offices to the east and southeast, a new Metro stop set to open in the area.

In less than two years, the new convention center has displaced more than 60 of 487 -- about 13 percent -- of Chinatown's residents of Asian descent, sent property values skyrocketing and attracted the eye of developers -- all of this hastening Chinatown's already steady decline.

Most young Chinese have already left Chinatown for the newer housing and less crowded living conditions of the suburbs. The population of the area has dropped by more than half since 1960 and only three groups of Chinese remain today: the elderly who have lived for years in Chinatown and are afraid to leave; the Chinese businessmen, many of whom have supported the new convention center, arguing that it will increase business to restaurants and shops; and the newly arrived immigrants, many from Vietnam, who speak little English and find safety in the Oriental faces and traditions of the area.

To the elderly Chinese, redevelopment is a worrisome reminder of 1936, when Chinatown, then at Third Street and Pennsylvania Avenue NW, was demolished to make way for the maze of municipal and federal office and court buildings just south of Judiciary Square. Other old world ethnic communities along the base of Capitol Hill also fell to the wreckers' ball: Little Italy and Litte Athens. Only Chinatown regrouped, says Kim Hoagland of the Historic American Building Survey, in part because Chinese restaurateurs secretly hired a real estate agent to set up a deal to move them as a group to the 600 block of H Street. Today's Chinatown grew from there.

Chinatown has for decades been a city within a city, a bedroom and commercial hub influenced by ancient old world traditions, a world apart from federal and municipal Washington. Chinatown still has its own unofficial mayor, its own family and professional associations, credit unions, grocery stores, restaurants, shops and other ways to care for its own.

But that, too, is changing as the Chinese lose control over their community to the forces of urban renewal and high-stakes speculative development, as did the poor blacks of Capitol Hill and Shaw.

"The pressure is building," says Harrison Lee, whose last name is the same as many Chinatown residents who are unrelated. The "mayor" of Chinatown, Lee is a retired CIA employe, Fairfax resident and chairman of the Chinese Consolidated Benevolent Association, an umbrella group for 21 Chinese associations and organizations. "Not only have people been displaced by the convention center and the demolition of buildings around it, but Chinese people are concerned that . . . their culture and their cohesiveness will be dissipated."

One of the forces at work is the pressure for modern development in the area. "The only area where there is a significant amount of land for development in the future is the Chinatown area," says Richard Carr, head of acquisition for the Oliver T. Carr Co., the city's most aggressive downtown developer.

"Thee is virtually nothing left west of 16th Street," he says. "The next group of buildings to be developed will be along the Franklin Park area [near 14th and I streets NW] and Pennsylvania Avenue. Once the convention center is built, the focus will be around the Chinatown area. There is no question about redevelopment coming there."

Davis Lee, 74, past chairman of the On Leong Merchants Association and owner of the China Doll and Jade Palace restaurants on H Street, says he and other merchants get almost daily offers for their property -- offers that are becoming hard to refuse. The Chinese Consolidated Benevolent Society, for instance, was offered $280,000 last year for it aging row house at Eighth and H streets NW, for which the association had paid $20,000 in the 1950s. After much deliberation, the association refused.

Most Chinese, however, do not have the luxury of keeping their property, says Harrison Lee, because only about 25 percent of Chinatown is actually owned by Chinese, leaving the future of many Chinese businessmen in the hands of absentee landlords.

But for all the fear about the impact redevelopment will have on Chinatown, some insist the boom will actually help the area, turning it into a thriving tourist haven of restaurants, boutiques and specialty stores.

"In the K Street area alone, from Vermont Avenue to 20th Street NW, there are about 18 Chinese businesses and even more that have spread out to the suburbs while Chinatown only has about 10 restaurants and Chinese businesses," says Phillip Lee, a Washington lawyer and immigrant from Hong Kong who was raised in New York City's Chinatown.

"My hypothesis is that when you have more commercial activity, more Chinese will want to live in Chinatown."

Not everyone agrees, and Harrison Lee says the most likely redevelopment to occur in Chinatown is commercial since it is more profitable than residential development. Carr says commercial development is likely because there is a great demand in the area for office and commercial space.

In an effort to keep some Chinese living in Chinatown, a local nonprofit Chinese development company this month will begin construction of a 152-apartment complex, the Wah Luck House at Sixth and H streets NW. The complex of mostly one-bedroom apartments is for the elderly and low income people, however, and it is clear that Chinatown will never again be the bustling family neighborhood it was in the 1940s and 1950s.

Already, Chinatown's elders complain that their now suburban grandchildren have adopted an American life style. Many Chinese youths cannot read Chinese and some cannot even speak the language, which means their heritage is slipping away. In a sense, success in America has been a detriment to maintaining that culture.

"I feel proud of my grandchildren -- three of them have already gone to college -- but they are losing their culture now and they don't speak much Chinese," says Davis Lee, who came to this country as a poor immigrant 63 years ago.

Like his father and grandfather before him, Davis Lee, named Lee Sun Wah before an American elementary school teacher changed his name to Davis Lee, was a member of an immigrant Chinese work force used in building railroads and doing other backbreaking work at the turn of the century. Although men were welcome to work, Chinese women were not allowed into the country until World War II.

Many of Chinatown's elderly, like Henry Ng and his roommate Lem Lee, 89, are bachelors who never saved enough money to return to China or bring wives here, even after the prohibition against Chinese women was lifted.

Davis Lee, a former cook for the U.S. Army, was one of few who did save enough to bring his family to the United States in 1947. But like others of Chinatown, he has had difficulty keeping his family together in traditional Chinese ways. Only three of his five children live in the Washington area -- in Hyattsville, Falls Church and Springfield. One of them, physician Toon Lee, practices in Chinatown and a daughter, Emma Lee, helps her father run the China Doll.

"I remember how the old Chinese used to sit out on the stairs," says Tom Lee, the manager of Chinatown Tropicals fish store and a frequent visitor to Chinatown from his Northwest home as a youth. "They would read their Chinese newspapers and play mah-jogging with ivory tiles and Chinese characters written on them.

"Most of the old Chinese want their sons to keep up the customs," he says, "but times have changed."

Yet, the culture lives on in the suburbs in innumerable little ways, says Charles Belanger, the non-Chinese manager of the Lee Funeral home in Chinatown.

"It is still the custom among Chinese to have funerals on Sunday, the only day when the old Chinese laundries were closed," says Belanger, called "Charley Brown" by Chinese friends. "Some of the Chinese request that when they die, the hearse be driven through Chinatown so they can pay their last respects."

As Henry Ng shuffles about his tiny community, hearing the drone of deisel construction trucks and passing the boarded-up buildings and newly vacant lots, he tells a visitor through an interpreter that the changes he has seen have reduced life in Chinatown to basic survival -- "a place to eat, a place to stay."

Ng, smiling faintly, says that he has been pushed and shoved many times in life. He is resigned to accept whatever comes. And as he slowly walks away from the doorway of the Wah Shing Social Club, the din of rush-hour traffic down H Street grows louder, and the drone of the diesel construction trucks goes on.