Paper/Poster/Presentation Title
Decision support for control of salt and methylmercury export from managed seasonal wetlands
Keywords
mercury, watershed, wetlands, decision support, WARMF model
Start Date
25-6-2018 3:40 PM
End Date
25-6-2018 5:00 PM
Abstract
Monomethylmercury (MeHg) is a toxic mercuric compound that, even at very low concentrations, can lead to mercury (Hg) bioaccumulation within the aquatic food web and cause high levels of MeHg contamination in fish and humans. The behavior of Hg in the environment depends on numerous chemical, physical, and biological factors that vary in time and space driven by biogeochemical and hydrodynamic processes. Managed seasonal wetlands are a major source of both MeHg and salinity to the Sacramento – San Joaquin Delta which discharges into San Francisco Bay and is the source of drinking water for 2/3 of California’s citizens. Whereas the source of the wetland salinity is well established – present in parent soils and in supply water - the primary sources of Hg and MeHg contamination have yet to be established. Management options to control Hg and MeHg export require a scientifically valid conceptual model as a basis for action. The Watershed Risk Management Framework (WARMF) water quality simulation model has been used extensively to provide TMDL-related decision support for salinity and nutrient TMDL’s impacting the water quality-impaired San Joaquin River. Successful calibration of the WARMF salinity and mercury modules in the WARMF model that simulate non-point discharges from seasonal managed wetlands requires improvements to the existing method for simulating wetland hydrology. This paper describes how this was accomplished. The calibrated WARMF salinity and mercury model will be used to guide future wetland monitoring and assess likely success of innovative wetland management practices to limit salt and MeHg export.
Decision support for control of salt and methylmercury export from managed seasonal wetlands
Monomethylmercury (MeHg) is a toxic mercuric compound that, even at very low concentrations, can lead to mercury (Hg) bioaccumulation within the aquatic food web and cause high levels of MeHg contamination in fish and humans. The behavior of Hg in the environment depends on numerous chemical, physical, and biological factors that vary in time and space driven by biogeochemical and hydrodynamic processes. Managed seasonal wetlands are a major source of both MeHg and salinity to the Sacramento – San Joaquin Delta which discharges into San Francisco Bay and is the source of drinking water for 2/3 of California’s citizens. Whereas the source of the wetland salinity is well established – present in parent soils and in supply water - the primary sources of Hg and MeHg contamination have yet to be established. Management options to control Hg and MeHg export require a scientifically valid conceptual model as a basis for action. The Watershed Risk Management Framework (WARMF) water quality simulation model has been used extensively to provide TMDL-related decision support for salinity and nutrient TMDL’s impacting the water quality-impaired San Joaquin River. Successful calibration of the WARMF salinity and mercury modules in the WARMF model that simulate non-point discharges from seasonal managed wetlands requires improvements to the existing method for simulating wetland hydrology. This paper describes how this was accomplished. The calibrated WARMF salinity and mercury model will be used to guide future wetland monitoring and assess likely success of innovative wetland management practices to limit salt and MeHg export.
Stream and Session
B2: Hybrid modelling and innovative data analysis for integrated environmental decision support
Organizers: Peter A. Khaiter, Marina G. Erechtchoukova