Changes at the top of two of the State Department's regional bureaus have brought a series of shifts among senior aides.

Rozanne L. Ridgway, the new assistant secretary for European and Canadian affairs, is bringing in a new front office team. Among the new faces are William M. Woessner, former deputy chief of mission in West Germany, who will be principal deputy assistant; deputy assistant secretaries Charles H. Thomas (formerly deputy chief of mission in Belgium) and M. James Wilkinson, who was Ridgway's deputy when she was ambassador to East Germany. Don J. Donchi, former counsel general in Zagreb, Yugoslavia, is the new public affairs chief for the Bureau of European and Canadian Affairs.

Over at the Inter-American Affairs Bureau, new Assistant Secretary Elliott Abrams (formerly head of the Human Rights Bureau) has moved William G. Walker from his post as deputy chief of mission in Bolivia to be the new deputy assistant for Central America. Walker's new assistant is Richard H. Melton, formerly deputy chief of mission in Uruguay.

Robert S. Gelbard, former director of the Office of Southern Africa Affairs, has been named deputy for South America and Paul D. Taylor, former deputy chief of mission in Guatemala, is the new deputy assistant for Latin American economic affairs.

Two new Central American ambassadors also are heading for their posts this week: John Ferch, former head of the U.S. interests section in Cuba, is the new envoy to Honduras; and Edwin Corr, former ambassador to Bolivia, was sworn in Friday as ambassador to El Salvador.

And Thursday the White House announced that President Reagan intends to name three more ambassadors.

Robert G. Houdek, deputy chief of mission in Kenya, was nominated to be ambassador to Uganda, replacing Allen Clayton Davis. Jean Broward Shevlin Gerard, U.S. permanent representative to UNESCO in 1981, was nominated to be ambassador to Luxembourg, succeeding John E. Dolibois. And Michael Sotirhos was nominated to be ambassador to Jamaica. Sotirhos, who would succeed William Alexander Hewitt, is chairman of the board of Ariston Interior Designers Inc. of New York.

-- Spencer Rich, Don Oberdorfer and Joanne Omang