FOR seven years, farmer Yang Yufu has remade shoes, fixed appliances, and sold glasses and plastic buckets to scratch out a living in the city.
In the best of months, he earns almost $100 to rent two rooms and support his mother, brother, and sister. Only his father remains at home to farm the tiny family plot in Zhejiang Province and maintain the family's claim to the land.
"The main problem in our county is there is so little land, but the population is growing," said Mr. Yang, who lives in Shandong's provincial capital without a permanent registration.
He left his home in Zhejiang because the family could not live on the meager farm income, and job opportunities nearby were scarce.
Millions of poor rural Chinese are on the move, flooding fast-growing coastal provinces and eroding government control of the country's huge population.
This "floating population," including job-seekers, tourists, and students, has helped fuel the prosperity sweeping China's eastern seaboard, the vanguard of market-style economic reforms.
Their presence in the cities, now allowed on a temporary basis of up to one year, reflects looser social controls in China, where residency registration has been a cornerstone of Communist power. Each Chinese is registered to live in a certain place, and until now was not allowed to relocate without official approval.
"Migration is like the law of nature. It is nothing to be afraid of," says Governor Zhao Zhihao of Shandong, where migrants registered as temporary state workers increased 18 percent to 1.6 million last year.
The unprecedented magnitude of the rural migrant tide, with many shifting between countryside and cities and among provinces without steady jobs or official permits, is raising alarm.
Urban unemployment is on the rise, crime is spreading, birth rates among the migrants increase outside the bounds of official controls, and worries of social unrest grow as unemployed rural migrants swamp the cities.
According to figures from the State Statistical Bureau published in the Chinese press, more than 50 million rural migrants now live in 23 large cities.
With the surplus labor force in the countryside estimated at more than 120 million people and growing, the exodus of rural workers is projected to increase at an annual rate of 10 million people during this decade, according to a report from the Chinese Academy of Social Sciences, a government think tank.
"Government control over people's movements is breaking down along with control over travel, what jobs they hold, and how many kids Chinese can have," says a Western economist in Beijing.
For farmers, the migration to the cities mirrors the worsening problem of unemployment in the villages, where the government first began to dismantle Marxist economies 14 years ago.
Recently, the Ministry of Agriculture said 19 million township enterprises, which already account for one-third of China's industrial output and are reaching the limits of growth, will have to absorb 200 million surplus rural laborers by the turn of the century.
At that time, China is projected to have a half-billion farmers, many of whom face bewildering difficulties. The amount of cultivated land fell 1.5 percent last year as towns and cities requisitioned farmland for economic development zones or cash-strapped farmers let land lie fallow.
Despite four years of record crops, the income of many farmers has dropped and burdens of higher costs and fees and taxes paid to local governments have increased. As a result, Chinese newspapers report, the seasonal influx of rural job-seekers to the cities during the Chinese New Year in late January was larger than normal.
Chinese and Western analysts say that rural residents are also fleeing to the cities to escape oppressive implementation of family planning by local officials. According to a report in Wenhui Daily, a Shanghai newspaper, one-eighth of births beyond family planning targets in China are attributed to rural migrants.
The lure of the cities, with higher incomes and flashy consumer products, is so great that Chinese newspapers report cases of permanent urban residence registration being sold by corrupt officials for more than $1,000 in Zhejiang.
The migrants also are stirring urban resentment because the job market in the cities is tightening. Lacking jobs, gangs of beggars from poor provinces are being organized in Beijing, Shanghai, Guangzhou, and Shenzhen and are creating public-order problems, according to the New China News Agency.
"The labor situation is balanced now, but in the future, there will be more job applicants than recruiters, because many work units have financial problems and can't even afford to pay their regular workers," said Liu Dong, as job-seekers scrutinized ads for cooks, maids, waitresses, and mail room workers posted on a board outside his employment agency office in Jinan.
But Chinese and Western observers predict it will be difficult to stop the exodus. On Nanmen Bridge in Jinan, clusters of farmers sell floor coverings and hire themselves out for carpentry and other home improvements.
Wang Hongfeng came with 15 others from his village in Anhui Province. Last year, pests destroyed the village cotton crop and plunged many families into debt, forcing the men to seek work in Jinan. Living in three rented rooms, the men will soon have to return home, because their temporary residence registration is running out and crops need to be planted. "But we will come again next year," says Mr. Wang.