HR: 0800h
AN: B41C-07    [Abstracts]
TI: Increases of riverine dissolved inorganic carbon fluxes over the Mississippi River Basin: The role of changing water-throughput and watershed H⁺ inputs.
AU: * Oh, N
EM: neung-hwan.oh@yale.edu
AF: Yale University, 205 Prospect St. School of Forestry and Environmental Studies, New Haven, CT 06511, United States
AU: Raymond, P A
EM: peter.raymond@yale.edu
AF: Yale University, 205 Prospect St. School of Forestry and Environmental Studies, New Haven, CT 06511, United States
AB: Previously about 50% of alkalinity flux increase over the last 50 years from the North America's largest river, the Mississippi was reported. The mechanism for this initial finding was determined to be an increase in water throughput. Extending the research, we investigated spatial variation on riverine alkalinity fluxes from the Mississippi River basin using US Geological Survey Water Data and a variety of GIS layers including yearly precipitation. Since flux is estimated by multiplying concentration and discharge, the increase in alkalinity flux can be due to increase of both concentration and discharge. Results demonstrate that increases in both precipitation and the discharge normalized concentration contributed significantly to changes in alkalinity flux and demonstrate that the relative contributions of the both on the flux was greatly dependent on different hydrologic regions, indicating the importance of spatial variation on riverine alkalinity flux.
DE: 0428 Carbon cycling (4806)
DE: 1625 Geomorphology and weathering (0790, 1824, 1825, 1826, 1886)
DE: 1630 Impacts of global change (1225)
DE: 1879 Watershed
DE: 1886 Weathering (0790, 1625)
SC: Biogeosciences [B]
MN: 2007 Joint Assembly