BEIJING — To hear Tibetans tell it, a rising tide of Han Chinese migrants is flooding into their homeland, diluting its character and taking many of the jobs.
They say that anger over the "Han invasion" has inflamed tensions and prompted protesters in the Tibetan capital of Lhasa earlier this month to set scores of Han Chinese shops ablaze in a spasm of rioting.
Authorities offer a different story. They say that Tibetans looking to stir up trouble are exaggerating the magnitude of the Han Chinese migration. They say that ethnic relations in Tibet are harmonious, and that political motives underlie the March 14 rioting. Even if more Han Chinese are moving to Tibet, they say, it's lifting the fortunes of the whole region.
"Their business activities have greatly enriched and promoted Tibet's economic development," said Tanzen Lhundrup, a scholar with the government-financed China Tibetology Research Center in Beijing.
The demographic issue is turning into a major point of dispute in explaining why peaceful protests by monks that began March 10 in Lhasa flared a few days later into bloody rioting and sparked demonstrations in at least 40 other areas across a vast swath of southwest China.
The unrest is now thought to be bigger in scale and more widespread than the late 1980s social strife that led to the declaration of martial law in Tibet.
More than nine out of 10 of China's 1.3 billion people are ethnic Han.
Han migration into Tibet began early in the decade and speeded up in 2006 with completion of a $4.2 billion railway across permafrost on the Tibetan Plateau that linked the remote "Land of the Snows" with the rest of the nation for the first time.
"It's been accelerating at a dramatic rate since 2000," said Ronald Schwartz, a Tibet scholar at Memorial University in St. John's, Canada. He said that Han Chinese stayed in urban areas. "If you go out to the villages, you won't see Chinese people. You only see them in Lhasa, Shigatse and the cities."
Lhundrup, speaking at a news conference earlier this week set up by the State Council, said that a census in 2000 showed that 92 percent of the population was of Tibetan ethnicity in the Tibet Autonomous Region, a Himalayan plateau that's about one-eighth the total area of the nation. Ethnic Tibetans also live outside that area.
He said that supporters of the Dalai Lama, the exiled spiritual leader of Tibetan Buddhists, had latched on to the migrant issue as one of their banners for independence.
"The issue of migration into Tibet is an excuse by the Dalai clique to serve its own political purposes," Lhundrup charged.
Schwartz noted, though, that the majority of Han settlers and merchants in Tibet retain residences elsewhere, so they aren't tallied in official numbers.
He estimated that "maybe two-thirds" of Lhasa's population is now Han, and that "it's dramatically changed the complexion of the city within a few short years."
"The only area that is really Tibetan is the Old City," he said, referring to an area of central Lhasa that may have a population of about 550,000.
Tibetans in exile say that the flood of migrants dilutes Tibet's distinct cultural identity. They say the ethnic Han bring development but also new lifestyles that weaken — and even defile — values in the Tibetan capital, which brims with monasteries and temples.
"Lhasa is a holy place. You never heard about these brothels, karaoke bars and discotheques before," said Tashi Choephel, a researcher at the Tibetan Center for Human Rights and Democracy in Dharamsala, India, the seat of Tibet's government in exile.
While commerce draws Han Chinese to Tibet's cities, Beijing also has pumped billions of dollars into the region, creating new government jobs.
Tibetans say they're strongly disadvantaged in getting those jobs because they don't speak Mandarin Chinese well, and that creates resentment against the Han.
"They are not tied into economic networks. They don't have contacts to get the jobs that have dropped into Lhasa," Schwartz said.
With 56 minority groups spread across China, authorities preach ethnic respect and tolerance, often sweeping signs of discontent under the rug and repressing any group — such as the Muslim Uighurs in the far west — in which calls for independence emerge.
"The ethnic relations in China are very harmonious," Lhundrup said, adding that Tibetans who suggest otherwise are doing so "to achieve the goal of splitting the motherland."