A wave of poor minorities is about to come of age in Boston, dominating the city’s workforce, raising children, and flooding “many spheres of life in this city,’’ according to a new study of blacks in Boston.

About a third of all blacks and Latinos in Boston are 17 or under while only about 13 percent of whites are in that age group, the report found. But many of those young minorities face educational and socioeconomic disadvantages, sparking concern among community leaders that they will not be equipped for the responsibilities that await them.

Unless policy makers, business leaders, and community-based organizations collaborate on ways to prepare them, the community leaders say, Boston will have a labor pool of unemployed, underemployed, or unemployable adults.

“We need to invest in them to make sure they have the skill set and competencies in order to effectively drive the engine or apparatuses to make this city work,’’ said Darnell L. Williams, president of the Urban League of Eastern Massachusetts, which commissioned the report with the Boston NAACP and the William Monroe Trotter Institute at the University of Massachusetts Boston.

The 49-page report, “The State of Black Boston’’ by James Jennings, a Tufts University professor of urban environmental policy, analyzed 2006-2008 census data to provide a demographic snapshot of Boston’s black community.

The picture included some findings that highlighted long-recognized issues in Boston — significant disparities in jobs, income, housing, and education, adding up to what the report called “vast inequalities reflected in the life experiences of blacks and other people of color compared to whites.’’

The report said that in general, the large number of young minorities on the cusp of adulthood has gone largely unnoticed.

“It might not be melodramatic to exclaim that black and Latino children are spearheading a quiet demographic revolution in this city, with many kinds of social and economic implications,’’ Jennings wrote in his report.

The report found that about a quarter of Boston residents are black, and that about a third of those are foreign-born. Blacks had the highest rates of unemployment of any group, and half the household income of whites.

Particularly alarming, Jennings said, were the vast segments of minority youth living in families so poor that they received federal assistance to buy food — half of all school-aged blacks, a third of black kindergartners, half of Latino kindergartners.

“What shocked me is the number of black and Latino children in kindergarten who are on food stamps,’’ he said. “What are we doing today to make sure these children have opportunity to, as the old saying goes, move up the socioeconomic ladder?’’