Information Center for the Environment

Riparian habitats in the California hardwoods zone are slowly being converted from natural landuses to permanently anthropogenic landuses. Riparian habitat is important for species diversity, water quality, and recreation. CA Department of Forestry and Fire Protection (CDF) Hardwoods Rangeland Monitoring Project's map of the riparian areas in the hardwoods zone was combined with the UCSB California Gap Analysis Managed Areas map to show the area of the riparian habitat in the study not protected from development. Using ARC/INFO GRID, it was found that, of the approximately 2,780,000 acres of riparian mapped by CDF, 65% is privately owned and not managed for biodiversity. A digital elevation model (DEM) was used to determine which riparian areas were on slopes of <10¦ . Riparian habitat on a slope of <10¦ and privately owned is at a higher risk of development and represents 35% of the total riparian habitat in the study area. In addition, to the management status and slope of the riparian hardwood habitat, the population growth rate of the study area counties was examined. The population of California is estimated to increase from 23,383,000 in 1996 to 47,507,000 by 2020, with 44% of the population growth expected in occur in the counties with riparian hardwood habitat. In order to protect the riparian habitat in the hardwoods zone, a coordinated effort between 42 counties in the hardwoods zone is needed.