Understanding the bioavailability of nanomaterials to aquatic animals and developing monitoring tools are crucial research needs to determine the environmental implications of nanotechnology. The unique physicochemical properties of nanomaterials influence their interactions in the environment and hence their bioavailability and toxicity. In all of these projects, phosphorus analyses of study samples have been included and compared with other measured environmental parameters making phosphorus cycling a unifying focus.Īssessing bioavailability and toxicity of engineered metallo-nanoparticles in aquaticĮnvironments using enriched stable-isotope tracers and biodynamic modellingĮngineered nanomaterials are released into the environment as a result of the rapid commercialization of nanotechnologies. Simon's research includes the Upper Klamath Lake, Oregon, to examine the phosphorus cycle considered responsible for the algal growth in, and euthrophication of, the lake. This resulted in a study of bottom sediments in which significant concentrations of oxytetracycline were identified. Data from the sediment analyses of tributaries to the Chesapeake Bay raised the question of whether there was some component of the sediment that would affect microbial activity in the sediment. Phosphorus cycling was the focus her next major study in the Chesapeake Bay watershed. The study of the role of algae in the cycling of metals was extended in the 1990’s to the USGS South Florida Everglades study of mercury in the environment. Following the Potomac River study, Simon joined the Toxics Program's study of cycling of chromium III and VI in sediment interstitial water. Her early research focus was on cycling nitrogen between sediments and the water column in large areas of shallow water.
Nancy Simon: Nancy Simon began work for the USGS in the late 1970’s when she joined the Potomac River Estuary Study, the forerunner of the present Chesapeake Bay study.
#NANCY SIMON HOW TO#
This presentation discusses possible forms of phosphorus in sediments, the methods for determining the concentrations of these forms in sediment samples, and how to evaluate sediment data with regard to mobility of phosphorus in aqueous environments. The forms of phosphorus in bottom sediments dictate whether the sediments serve as a source of phosphorus to the water column (internal loading), or whether the sediments retain phosphorus delaying or preventing transfer of this nutrient from the sediment to the overlying water column. Internal loading of phosphorus is often a major factor in the eutrophication of lakes, reservoirs, and rivers. Sediments as a Source and Sink for Phosphorus – Internal Loading versus Retention of Nutrients The presentations, and some information about Nancy and Marie follow: Details are included at the end of this note.
Please let us know in you plan to attend and if you are interested in staying for lunch. The Minnesota Water Science Center is pleased to announce the next lectures, by Nancy Simon and Marie Noële Croteau, on September 27, at the Minnesota Water Science Center.įollowing the morning presentations we will have an informal pizza lunch at the office to provide a time to talk informally with Nancy and Marie.
USGS Water Science Centers are located in each state.Įach year the USGS, National Research Program, offers lectures on various topics to selected field offices. Search the Minnesota WSC: ABOUT THE MINNESOTA Home Information/Data Projects Publications Flood NAWQA Office Contact Other USGS
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