A combination of trade, wage and agricultural factors points to continued high levels of illegal immigration from Mexico and possibly a gradual increase in numbers over the next five to 10 years, experts predict.

• A growing stream of agricultural imports into Mexico could displace more farm workers and encourage them to head for the U.S. border.

• As more farm workers arrive, agricultural pay scales will decline -- making it harder for the new arrivals to keep up economically.

• In California's San Joaquin Valley, the state's agricultural heartland, nine of every 10 farm workers are Mexican-born -- and welfare-dependency rates are in the double digits.

• Economist Edward Taylor and Phil Martin, both of the University of California-Davis, have found that for every 100 farm jobs added, 139 more people living in poverty are added.

The situation has led Taylor to warn that the U.S. "risks recreating rural poverty via immigration."

Some 150,000 Mexicans enter the U.S. illegally each year, in addition to a large number who migrate legally. The Immigration and Naturalization Service reports that 160,000 arrived here legally in 1996.

It estimates that 2.7 million Mexicans may be in the U.S. illegally -- 2 million of whom are in California.