title: Nutrient Loading through Submarine Groundwater Discharge and Phytoplankton Growth in Monterey Bay, CA.
abstract: We quantified groundwater discharge and associated nutrient fluxes to Monterey Bay, California, during the wet and dry seasons using excess (224)Ra as a tracer. Bioassay incubation experiments were conducted to document the response of bloom-forming phytoplankton to submarine groundwater discharge (SGD) input. Our data indicate that the high nutrient content (nitrate and silica) in groundwater can stimulate the growth of bloom-forming phytoplankton. The elevated concentrations of nitrate in groundwater around Monterey Bay are consistent with agriculture, landfill, and rural housing, which are the primary land-uses in the area surrounding the study site. These findings indicate that SGD acts as a continual source of nutrients that can feed bloom-forming phytoplankton at our study site, constituting a nonpoint source of anthropogenic nutrients to Monterey Bay.
authors.affiliation: †Department of Earth and Planetary Sciences, University of California Santa Cruz, 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Alanna L
authors.initials: AL
authors.lastname: Lecher
authors.affiliation: ‡Earth System Science, University of California Irvine, Irvine, California 92617, United States.|⊥Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California 95064, United States.
authors.forename: Katherine
authors.initials: K
authors.lastname: Mackey
authors.affiliation: §Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, California 95064, United States.
authors.forename: Raphael
authors.initials: R
authors.lastname: Kudela
authors.affiliation: ∥Monterey Bay Aquarium Research Institute, Moss Landing, California 95039, United States.
authors.forename: John
authors.initials: J
authors.lastname: Ryan
authors.affiliation: †Department of Earth and Planetary Sciences, University of California Santa Cruz, 1156 High Street, Santa Cruz, California 95064, United States.
authors.forename: Andrew
authors.initials: A
authors.lastname: Fisher
authors.affiliation: §Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, California 95064, United States.
authors.forename: Joseph
authors.initials: J
authors.lastname: Murray
authors.affiliation: †Department of Earth and Planetary Sciences, University of California Santa Cruz, 1156 High Street, Santa Cruz, California 95064, United States.|⊥Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California 95064, United States.
authors.forename: Adina
authors.initials: A
authors.lastname: Paytan
mesh_terms: D000383:Agriculture; D061006:Bays; D002140:California; D004784:Environmental Monitoring; D060587:Groundwater / Q000032:analysis* / Q000737:chemistry; D009566:Nitrates / Q000032:analysis*; D010839:Phytoplankton; D012822:Silicon Dioxide / Q000032:analysis; D014876:Water Pollution / Q000032:analysis*
chemical_list: D009566:Nitrates; D012822:Silicon Dioxide