The Effie Yeaw Nature Center, a 77-acre natural habitat preserve and learning center in Carmichael, faces possible closure. The preserve is making the transition from being run by Sacramento County to being run by nonprofit organization, the American River Natural History Association (ARNHA), which currently is the center's second largest contributor, behind the county. However, the state budget may not cover expenses for the transition period, which could take years, park employees say. If ... tonyn