Elizabeth Stumpner
Science and Products
Modeling Nitrogen Reduction Benefit to Invasive Aquatic Vegetation vs. Native Phytoplankton
Phytoplankton comprise the bottom of the aquatic food web and the abundance of phytoplankton serves as an indicator of healthy aquatic habitats. In the Sacramento-San Joaquin River Delta (Delta), competing with phytoplankton for required nitrogen, invasive aquatic vegetation (IAV) has increased exponentially in recent years. Once established, IAV can negatively impact local ecosystems and...
Effects of Aquatic Vegetation on Water Quality and Residence Time in the Bay-Delta
The spread of invasive aquatic vegetation in the Sacramento-San Joaquin Delta is having a profound impact on the Delta’s natural habitat. The presence of these “aquatic weeds” has been shown to alter water velocity and increase water clarity, posing threats to native fish species, specifically the threatened Delta Smelt. These aquatic plants can also affect the foodweb by altering nutrient,...
Geochemical data for water, streambed sediment, and fish tissue from the Sierra Nevada Mercury Impairment Project, 2011–12
This report presents geochemical data for surface water, streambed sediment, and fish tissue samples collected during low-flow conditions in 20 to 24 Sierra Nevada streams during 2011 and 2012. The dataset is part of a larger study designed to assess the factors that control mercury concentrations in fish tissue and to develop a model that...
Stumpner, Elizabeth B.; Alpers, Charles N.; Marvin-DiPasquale, Mark C.; Agee, Jennifer L.; Kakouros, Evangelos; Arias, Michelle R.; Kieu, Le H.; Roth, David A.; Slotton, Darrell G.; Fleck, Jacob A.
Sediment accretion and carbon storage in constructed wetlands receiving water treated with metal-based coagulants
In many regions of the world, subsidence of organic rich soils threatens levee stability and freshwater supply, and continued oxidative loss of organic matter contributes to greenhouse gas production. To counter subsidence in the Sacramento-San Joaquin Delta of northern California, we examined the feasibility of using constructed wetlands...
Stumpner, Elizabeth; Kraus, Tamara E. C.; Liang, Yan; Bachand, Sandra M.; Horwath, William R.; Bachand, Philip A.M. A river-scale Lagrangian experiment examining controls on phytoplankton dynamics in the presence and absence of treated wastewater effluent high in ammonium
Phytoplankton are critical component of the food web in most large rivers and estuaries, and thus identifying dominant controls on phytoplankton abundance and species composition is important to scientists, managers, and policymakers. Recent studies from a variety of systems indicate that ammonium ( NH+4) in treated wastewater effluent decreases...
Kraus, Tamara E. C.; Carpenter, Kurt; Bergamaschi, Brian; Parker, Alexander; Stumpner, Elizabeth; Downing, Bryan D.; Travis, Nicole; Wilkerson, Frances; Kendall, Carol; Mussen, Timothy
Mercury, monomethyl mercury, and dissolved organic carbon concentrations in surface water entering and exiting constructed wetlands treated with metal-based coagulants, Twitchell Island, California
Coagulation with metal-based salts is a practice commonly employed by drinking-water utilities to decrease particle and dissolved organic carbon concentrations in water. In addition to decreasing dissolved organic carbon concentrations, the effectiveness of iron- and aluminum-based coagulants for decreasing dissolved concentrations both of...
Stumpner, Elizabeth B.; Kraus, Tamara E.C.; Fleck, Jacob A.; Hansen, Angela M.; Bachand, Sandra M.; Horwath, William R.; DeWild, John F.; Krabbenhoft, David P.; Bachand, Philip A.M.