Abstract

Analysis of Changes in Biological Soil Crusts Using Landsat Image Time Series for the Southern California Desert

Potter C and Weigand J

Developers of renewable energy installations in Southern California must monitor the impacts of operations of new facilities on fragile desert ecosystems. This study is the first to use Landsat satellite spectral data to map changes in the distribution of biological soil crusts (BSCs) across federal lands of the Lower Colorado Desert. The coverage of BSCs comprising >33% pixel area totaled 4008 Km2 in 1990, and increased to 4841 Km2 by 2014. The proximity of changing areas of BSC cover between 1990 and 2014 to known river flow channels such as the Lower McCoy Wash, Riverside County, CA) implied that flash floods associated with heavy precipitation events are important agents of change for BSC cover. These results have an immediate application for mapping the potential impacts of flash flood events around developed urban areas and utility-scale solar energy installations in the deserts of Southern California.