Libraries might be open 12 fewer hours a week, parks might have to drop their day-care service and tree-trimming service might be abandoned under the city's pending layoffs and budget cuts, according to a city report issued Wednesday.

In a preliminary report to the City Council, Mayor Antonio Villaraigosa detailed the first 542 out of the 1,000 positions to be eliminated and the impact on those departments, as tempers flared between council members over the cuts.

Councilman Richard Alarcon said he wanted the council more involved in the decision making.

"I don't want the city administrative officer negotiating with department heads and then coming to us with a neat package on where cuts will be made," Alarcon said. "That's a decision that we should make as elected officials."

Council President Eric Garcetti chided Alarcon for a motion he brought that would have had the general managers appear before the council to discuss the budget cuts.

"The departments can't do this in 24 hours," Garcetti said. "This is what we should be doing in our committees and deal with these issues."

Alarcon, however, said he believed the entire council should be involved in the reviews.

The 1,000 layoffs were authorized as part of the effort to cover a $212 million shortfall in this year's $7.01 billion budget and a projected deficit of $484 million next year.

City Administrative Officer Miguel Santana said his office has played a more active role in analyzing the cuts because the council has asked for more care in targeting programs and services.

"You asked us to be surgical in the cuts, and that's why it is taking so long to report back to you," Santana said.

Deputy Mayor Matt Szabo said officials are taking a strategic view in evaluating the cuts for this year and the potential 4,000 for next year.

"The cuts are not going to be across the board," Szabo said. "Some departments will be asked to do more."

Councilman Tom LaBonge, who chairs the Arts, Parks, Health and Aging Committee, said city libraries would have to reduce their operations from 52 hours a week to 40.

"There is an absolute SigAlert out there," LaBonge said. "And it is going to cause greater congestion in our ability to deliver services. We are going to have to look at our libraries and how many hours we can keep them open. We have to look at our parks and decide which ones to close."

LaBonge, who won council support to keep the Department of Aging as a separate department, also said he is preparing a proposal that would exempt parks from paying for power, saving $20 million a year.

Some officials with the Department of Aging were concerned that consolidating it with another agency could jeopardize federal grant money. They said 85 percent of the department's budget comes from state and federal grants.

The council also was again advised that the cost of borrowing money is expected to go up because of a recent downgrade in its credit rating.

The city has $3.2 billion in outstanding bonds that are not affected but is expected to borrow more than $500 million this year to cover ongoing expenses.

"It is going to cost more," said Natalie Brill, who oversees the city's bonding. "The (credit rating agencies) talked about how we need to build up our reserves and make sure the city has money to cover its costs."

Garcetti said the agencies, particularly Moody's Investor Services, have given the city a roadmap to solve its problems that embraces a three-year plan suggested by Villaraigosa and Santana.