Patricia (Trish) Holden is a Professor in the Bren School of Environmental Science & Management at the University of California, Santa Barbara, and Director of the UCSB Natural Reserve System.  Her group researches across disciplines of environmental microbiology, microbial ecology, and environmental chemistry in the context of natural and contaminated sites.  Currently-funded projects include: 1) the urban water environment (UWE): integrating spatial relationships between urban infrastructure and subsurface contamination for diagnosing and addressing shallow groundwater micro- and conventional pollutants, 2) origins and fates of microbiological contamination in coastal watersheds, 3) the distribution and function of bacteria in subsurface soils, including controls on carbon availability and processing, 4) and microbial interactions with engineered nanomaterials in terrestrial ecosystems, towards understanding efficacy of safe-by-design nanomaterial engineering for hazard mitigation. Within the NSF- and EPA-funded University of California Center for Environmental Implications of Nanotechnology (UC CEIN), Holden is a Co-PI, and leads Theme 4 (Terrestrial Ecosystems Impact and Hazard Assessment) and the Carbonaceous Nanomaterial Working Group.  Holden’s B.S. and M.S. degrees are in Civil & Environmental Engineering from the University of Tennessee and Purdue University; her Ph.D. is in Soil Microbiology from U.C. Berkeley.  Holden’s professional work history includes eight years in the public and private sectors performing civil / environmental engineering planning and design.