Friday, December 5, 2014; 3:00 p.m.; LSci 175
Department of Chemistry & Biochemistry Welcomes:
Dr. Neal Blair
Professor, Department of Civil & Environmental Engineering, Northwestern University
“Resolving Carbon's Rainbow from Uplands to the Deep-Sea”
Our classic view of soil organic matter is that it is a penecontemporaneous mixture in which an aged, diagenetically altered component (humic material) is derived from previous inputs of photosynthetically-derived material. In reality, particulate organic carbon (POC) in surficial environments (both soils and sediments) is a mixture that can be fundamentally resolved into three general categories: contemporary (recently fixed C), aged (century to millennial time scale) and ancient (millions of years old). The relative abundances of these three C-pools are highly dependent on the environment and they evolve as particulates move across the landscape and bathyscape. In this talk, small mountainous rivers along tectonically active margins will be the primary topic because they can deliver suspended loads containing significant quantities of all three POC categories and are collectively responsible for nearly half of the terrestrial POC export to the global ocean. The sources of the C-pools, how we detect them, and their fates as they are transported across the landscape and bathyscape will be discussed. The implications of this research within the context of global environment change will also be considered.