Priya M Ganguli

California State University, Northridge | CSUN · Department of Geological Sciences

Fuhrmann B, Beutel M, Ganguli P, Zhao L, Brower S, Funk A, Pasek J. 2021. Seasonal patterns of methylmercury production, release, and degradation in profundal sediment of a hypereutrophic reservoir. Lake Reserv Manage. XX:XXX–XXX. Profundal lake sediment is an important site of toxic methylmercury (MeHg) production by anaerobic bacteria. This study...

Much of the surface water of the ocean is supersaturated in elemental mercury (Hg0) with respect to the atmosphere, leading to sea-to-air transfer or evasion. This flux is large, and nearly balances inputs from the atmosphere, rivers and hydrothermal vents. While the photochemical production of Hg0 from ionic and methylated mercury is reasonably we...

As a result of climate change, wildfires are becoming more frequent and intense. The 2018 California fire season was the most destructive on record, burning >7000 km2 (~1.8 million acres) of land, with the Woolsey Fire spreading throughout the western side of the Malibu Lagoon watershed. We conducted multiple storm event sampling campaigns during t...

Experimental plots in Great Sippewissett Marsh (Falmouth, MA USA) have been undergoing long-term (>48 years) fertilization through the application of commercial sewage sludge-based fertilizer. The experimental treatment focuses on the effect of added nitrogen on the salt marsh plots, but also supplies mercury (Hg) and other metals. This experiment...

Graphical abstract depicting sampling methods and major findings.

Study region: Hydrogeologic controls on seasonal land/sea exchange are investigated in Malibu, California, USA. Study focus: An assessment of regional groundwater/surface water exchange and associated biogeochemical transport in an intermittently open, coastal lagoon in California is developed using naturally occurring U/Th-series tracers. New hydr...

Rapid changes in the volume and sources of discharge during the spring freshet lead to pronounced variations in biogeochemical properties in snowmelt-dominated river basins. We used daily sampling during the onset of the freshet in the Fraser River (southwestern Canada) in 2013 to identify rapid changes in the flux and composition of dissolved mate...

Significance Mercury is a potent neurotoxin that accumulates in food webs, posing a global threat to environmental health. Marine mammals are common sentinel species for studying marine pollution; however, their potential role as vectors of contaminants to local ecosystems has rarely been addressed. By quantifying the concentration and chemical for...

Rapid changes in the volume and sources of discharge during the spring freshet lead to pronounced variations in biogeochemical properties in snowmelt-dominated river basins. We used daily sampling during the onset of the freshet in the Fraser River (southwestern Canada) in 2013 to identify rapid changes in the flux and composition of dissolved mate...

Submarine groundwater discharge (SGD) is an important conduit that links terrestrial and marine environments. SGD conveys both water and water-borne constituents into coastal waters, where these inflows may impact near-shore ecosystem health and sustainability. Multichannel electrical resistivity techniques have proven to be a powerful tool to exam...

We evaluated the influence of groundwater─seawater interaction on mercury dynamics in Maunalua Bay, a coral reef ecosystem located on the south shore of Óahu, Hawaíi, by combining geochemical data with submarine groundwater discharge (SGD) rates. During a rising tide, unfiltered total mercury (U-HgT) concentrations in seawater increased from ̃6 to...

Lead contamination in China has been extensively documented by scientists in China and elsewhere over the past two decades, as summarized in this review of articles published in peer-reviewed scientific journals. Sources of that contamination include (a) deposits from previous emissions of leaded gasoline, which was finally eliminated in the past d...

We measured total mercury (Hg(T)) and monomethylmercury (MMHg) concentrations in coastal groundwater and seawater over a range of tidal conditions near Malibu Lagoon, California, and used (222)Rn-derived estimates of submarine groundwater discharge (SGD) to assess the flux of mercury species to nearshore seawater. We infer a groundwater-seawater mi...

Coastal lagoons may play an important role in mercury biogeochemical cycling at the land-sea margin. Along the coast of California, these systems are seasonally dynamic, behaving as estuaries during the wet season and as lagoons in the dry season when ephemeral sand berms develop and isolate terrestrial freshwater from direct exchange with the ocea...

The Walker Creek intertidal delta of Tomales Bay, California is impacted by a former mercury mine within the watershed. Eleven short sediment cores (10 cm length) collected from the delta found monomethylmercury (MMHg) concentrations ranging from 0.3 to 11.4 ng/g (dry wt.), with lower concentrations occurring at the vegetated marsh and upstream cha...

Fluxes of total mercury (Hg(T)) and monomethylmercury (MMHg) associated with submarine groundwater discharge (SGD) at two sites onthe central California coast were estimated by combining measurements of Hg(T) and MMHg in groundwater with the use of short-lived, naturally occurring radium isotopes as tracers of groundwater inputs. Concentrations of...

Both the relatively high lead concentrations and their characteristic anthropogenic isotopic compositions attest to the widespread contamination of industrial lead in the western Equatorial and South Atlantic Ocean. Spatial gradients in those isotopic signatures evidence the conservative lateral transport of lead in oceanic water masses, while the...

The history of mercury in California is recorded in the sediments of San Francisco Bay. The Bay is downstream of 40 percent of the land area of California. Its watershed receives 80 percent of the rainfall in the State, because it rains more in the north. Three billion kilograms of sediments are annually flushed from the Central Valley watershed an...

Both the relatively high lead concentrations and their characteristic anthropogenic isotopic compositions attest to the widespread contamination of industrial lead in the western Equatorial and South Atlantic Ocean. Spatial gradients in those isotopic signatures evidence the conservative lateral transport of lead in oceanic water masses, while the...

Little is known about the amount and form of mercury released from inoperative mercury mines in the western United States. To address this, we measured mercury concentrations and speciation in water impacted by the New Idria mine. Total unfiltered mercury concentrations (UHgT) in acid mine drainage (AMD) (5.2 to 41 ng/L) were comparable to concentr...

Typescript. Thesis (M.S.)--University of California, Santa Cruz, 1998. Includes bibliographical references (leaves 98-100).