The Greenbelt City Council last week amended it ethics ordinance to include two state-required provisions.

In March, the council passed its original ethics law, which governs the behavior of elected and appointed city officials. The state later found that the ordinance lacked two necessary provisions, a city spokesman said.

One of the two new clauses requires higher ranking as well as lower ranking city officials to declare gifts. The second requires lobbyists who plan to spend more than $100 a year in the city to register.

In other business, the council considered a zoning variance that would allow a local woman to operate a day-care center in her home.

Several persons at the meeting testified in behalf of Elizabeth Sonnenfeld's request to operate the center during before- and after-school hours. Opponents expressed concern that the center would increase traffic in the Lakeside Drive area and might endanger the lives of local children because the neighborhood has no sidewalks.

The council also approved naming a pedestrian overpass across the Baltimore-Washington Parkway in honor of Gladys Noon Spellman, the former congresswomen from Maryland's 5th District. Spellman suffered a heart seizure while campaigning for reelection in November 1980 and remains in a coma.