With hikers and bikers crisscrossing a grassy hillside in front of her, California's state parks chief came to Santa Rosa Friday and defended the closing of 70 parks statewide, including Annadel State Park.

Ruth Coleman explained in an outdoor gathering at Spring Lake Park, just a short distance from Annadel, that a $22 million budget shortfall makes it impossible to keep open all the state's 278 parks.

Based on attendance and revenue, Jack London State Historic Park and Petaluma Adobe Historic State Park in Sonoma County also would be shut in July 2012 without passage of statewide tax extensions.

"In the case of Annadel, it doesn't make a lot of money," said Coleman, director of the Department of Parks and Recreation, as parkgoers strolled by under sunny skies. "It has high use but low revenue."

However, Coleman stressed there was still time to develop alternatives, which could involve partnerships with the private sector and non-profit groups. Local government could shoulder some of the costs, which in Sonoma County amount to about $1 million a year.

"We have a year to solve the problem," Coleman said. "I'm confident we'll find a solution."

Her remarks and those from state lawmakers were made at a special hearing of the Assembly parks committee convened at Spring Lake. Many of the 100 or so people listening under oak trees called for action.

Greg Sarris, chairman of a Sonoma County Indian tribe that is proposing a casino near Rohnert Park, vowed to contribute $2 million to $5 million a year for 20 years to state and regional parks.

The offer appeared to be contingent upon a compact with the governor to allow gaming at the casino owned by the Federated Indians of the Graton Rancheria.

Sarris urged state officials to look to tribal casinos elsewhere as a key source of park funding.

"The tribes themselves want to work to take care of the land," Sarris said.

Other efforts also are in the works to keep state parks open. The two others slated for closure are Austin Creek State Recreation Area near Guerneville and Sugarloaf Ridge near Santa Rosa.

Caryl Hart, Sonoma County's parks director, said a coalition of local groups was forming to determine how much money is needed and to identify money sources.

Already, county government is looking at a cooperative agreement to possibly handle operations and maintenance of some parks.

"There's a lot going on," Hart said. "There has to be. We can't just sit here and watch state parks close."

If they did close, it could cause all kinds of problems, a number of speakers said.

Facilities would fall into disrepair and could become havens for transients and marijuana growers.

The costs would multiply with lawsuits that would no doubt follow, said Assemblyman Jared Huffman, D-San Rafael, who chairs the parks committee and is carrying legislation to allow the special parks partnerships.

Huffman generated applause when he needled Coleman about putting Annadel on the hit list. He requested she provide internal documents surrounding her decision so the process would be more transparent.

"Never before in our history have we taken this kind of action," Huffman said. "We need our parks more now than ever."