Segregation of black pupils increased at a faster rate in Maryland's public schools than in those of any other state between 1980 and 1984, and the state's school system is the fourth most segregated in the country, according to a University of Chicago study released this week.

The reason for the state's high ranking is that while its black population has been growing in Baltimore and Prince George's County, where black pupils already were in the majority, the demographic changes have not been met by regional desegregation plans, the study said.

"We are not trying to lay blame or suggest that the segregation is intentional, just that there is real reason for concern," said political science professor Gary Orfield, one of the authors of the study with two other researchers at the university's National School Desegregation Project. "All our research shows that there is a very strong relation between racial segregation and economic segregation, dropout rates, low test scores, college entrance rates and other factors that have real consequences in an adult's life."

The study found that Maryland ranked fourth in two out of three categories the researchers used to measure segregation: It found that while blacks make up 37.2 percent of the total public school population, 79 percent of the state's black students attend mostly black schools. At the same time, white students made up 26.6 percent of the student body at schools attended by typical black students.

Orfield added that one reason Maryland led all states in increasing segregation was that most areas did not experience substantial changes in the 1980s, while black populations in the Washington suburbs and particularly Baltimore have been rapidly growing.

Between 1980 and 1984, the percentage of black pupils attending predominantly white schools in Maryland dropped from 33 percent to 21 percent. In the Baltimore area, the percentage of whites attending school with blacks dropped from 24.3 percent to 15.8.

Maryland school officials and education experts met the study's results with a combination of concern and skepticism. They acknowledged that while there is room for improvement, traditional methods of integration, such as busing, can go only so far in school districts that are predominantly black.

James McPartland, director of the Center for the Social Organization of Schools at Johns Hopkins University, said that while Maryland probably ranked in the top quarter of the most segregated school systems, he did not believe the problem was as severe as Orfield's study suggested.

"He picked an index that is sensitive to the racial proportion in the state. Maryland's minority population {at 25 percent} is the 13th highest nationally, so it makes sense that its schools would have a higher proportion of blacks," McPartland said. "You could also define a desegregated school system as one where each school looks like the average percentage of blacks and whites in the state."

Prince George's County school officials, who two years ago embarked on a voluntary school desegregation plan involving magnet schools as an alternative to busing, also took exception to the report.

They noted that the data used in the study only went up to 1984, the year the plan took effect. "Segregation can't be considered a Prince George's County problem any longer," said Superintendent John Murphy. "We have effectively corrected the problems in most of our schools and are confident that the rest will be racially balanced within the next five years."

"The number of white students is not the criteria by which we judge our schools," said school spokesman Brian J. Porter. "We would be proud to say that we had the state's highest test scores and we're predominantly black -- so what?"

Of 32 states surveyed, Illinois had the most segregated schools, followed by Michigan and New York.

Virginia had the 12th highest percentage of white students. The study found that that white students made up 47.6 percent of the student body at the school attended by the typical black student in the state, as compared to 26.6 in Maryland.