Engineering Commons^™

A Model To Predict Concentrations And Uncertainty For Mercury Species In Lakes, Ashley Hendricks

Dissertations, Master's Theses and Master's Reports

To increase understanding of mercury cycling, a seasonal mass balance model was developed to predict mercury concentrations in lakes and fish. Results indicate that seasonality in mercury cycling is significant and is important for a northern latitude lake. Models, when validated, have the potential to be used as an alternative to measurements; models are relatively inexpensive and are not as time intensive. Previously published mercury models have neglected to perform a thorough validation. Model validation allows for regulators to be able to make more informed, confident decisions when using models in water quality management. It is critical to quantify uncertainty; …

Factors Contributing To Elevated Concentrations Of Mercury And Pcbs In Fish In The Inland Lakes Of Michigan's Upper Peninsula And Lake Superior, Mugdha Priyadarshini

Dissertations, Master's Theses and Master's Reports

Mercury (Hg) pollution adversely affects ecosystems and human health. Mercury in the form of methylmercury (MeHg) bioaccumulates in aquatic ecosystems, thereby affecting fish, fish-eating wildlife and humans. The goal of this research was to clarify the effects of environmental factors on MeHg concentrations in fish in the inland lakes of the Upper Peninsula of Michigan. Of the 74 lakes for which data were available, 56 had fish mercury concentrations above the water quality guideline. Multivariate statistical analyses indicated different factors affect fish Hg concentrations in large and small lakes.

Polychlorinated biphenyl (PCB) compounds are a class of persistent, bioaccumulative and …

Assessing The Impacts Of Climate Change On The Surface Temperature Of Inland Lakes In Michigan, Kaitlin Reinl

Dissertations, Master's Theses and Master's Reports

The aim of this study was to validate and apply a lake model for predicting the susceptibility of small inland lakes in Michigan to changes in thermal regime and increased cyanobacteria growth as a result of future climate conditions. The Freshwater Lake Model was selected, tested for sensitivity to various inputs, and validated through comparison to observed conditions. The sensitivity analysis showed that the lake model was most sensitive to solar radiation, air temperature, and air humidity. Comparison of predicted climate data with observed conditions revealed highly variable climate model error. The lake model validation was conducted using 10 lakes …