Award Date

5-2009

Degree Type

Thesis

Degree Name

Master of Science in Water Resources Management

Department

Water Resource Management

First Committee Member

Shawn Gerstenberger, Chair

Second Committee Member

Charalambos "Lambis" Papelis

Third Committee Member

Von Winkel

Graduate Faculty Representative

Timothy Farnham

Number of Pages

107

Abstract

The Springs Preserve near downtown Las Vegas, Nevada contains a seven-acre constructed wetland. Springs Preserve managers are planning to use water from the constructed wetland to irrigate creeks immediately north of the wetland. These creeks will be used by a variety ofaquatic wildlife, including endangered amphibians sensitive to harmful metalloids, such as selenium, lead, and arsenic.

In an attempt to answer toxicological questions about contaminant concentrations in the constructed wetland, three metals and metalloids (selenium, arsenic, and lead), two nutrients (nitrogen and phosphorus), and the major ionic species were analyzed at four sampling locations for aqueous concentrations, in two separate sampling events, before and after a major flood event. It was hypothesized that metal and metalloid concentrations would decrease from inflow to outflow, nutrient concentrations would increase from inflow to outflow, and relative ion concentrations would fluctuate, from inflow to outflow. This was generally the case, with few exceptions. It was hypothesized that there would be a net loss in aqueous concentrations as trace metals, nutrients, and major ions exit the constructed wetland system during the flood event. However, the opposite was found to be the case, for reasons that will be described in the text. A oneway ANOVA and a paired T-test were used to analyze nutrients and metals. Ions were analyzed using Piper diagrams.

The results were that relative concentrations ofions, metals, and nutrients increased between well flushing events, there was a weak trend for metal concentrations decreasing, from inflow to outflow, and there was a strong trend for nutrient concentrations increasing, from inflow to outflow. Ionic concentrations increased, while relative abundances of ions stayed the same.

Keywords

Constructed wetlands; Environmental chemistry; Groundwater - Quality; Water quality management; Water - Toxicology

Disciplines

Environmental Chemistry | Environmental Health | Terrestrial and Aquatic Ecology | Water Resource Management

Language

English

Comments

Signatures have been redacted for privacy and security measures.