Interactions Between Climate, Vegetation, and Fire in the Santa Monica Mountains: A Remote Sensing Analysis

The Santa Monica National Recreation Area, the world's largest urban national park, is both home to a rich and fragile Mediterranean chaparral ecosystem, and in close proximity to highly urbanized Los Angeles. The Santa Monica Mountains are comprised of seven distinct ecoregions, characterized by changes in elevation (from sea level to 949 meters), moisture levels (with the central and western areas receiving more precipitation, up to 28 inches per year), and varying extent of urbanization. This project studied how wildfire changes vegetation and vegetation health across the ecoregions. Landsat data, due to its high spatial and temporal resolution, was used to measure changes in NDVI and NBI over time. Fire perimeters from the CAL Fire FRAP database and historical temperature and precipitation data were used to map the effects of changing climate on the fire regime, and the effects this has on vegetation health and recovery after fires. In situ observations were also made of fire recovery across ecoregions and after varying fire return intervals. This research will aid in understanding how different environmental factors (and variations at the ecoregion scale) affect an ecosystem's response to a changing fire regime. An understanding of the interrelations between climate, vegetation, and fire is necessary for future management and protection of a natural area that is ecologically rich, regionally varied, and highly accessible to a major metropolitan area.