Date of Graduation

5-2017

Level of Access

Restricted: Campus/Bates Community Only Access

Degree Name

Bachelor of Arts

Department or Program

Environmental Studies

Number of Pages

59

First Advisor

Holly Ewing

Abstract

Freshwater ecosystems worldwide are being subjected to eutrophication at an alarming rate. Lake Auburn is the unfiltered municipal drinking water supply for the cities of Lewiston and Auburn, Maine. Large, long lasting algal blooms coupled with a fish kill in 2012 brought attention to the degrading water quality in Lake Auburn. Extensive monitoring by multiple stakeholders has started to provide insight into the external and internal loads of nitrogen and phosphorus to the lake basin. Nitrogen and phosphorus have been identified as two key limiting nutrients that drive eutrophication in conjunction with factors such as light availability, stratification, and oxygen supply. In oligotrophic systems, phosphorus is believed to be most limiting. Historical surface water samples from four sites were analyzed by ICP-MS for total phosphorus. Many methods were attempted in the quantification of total phosphorus (TP). The process was complicated by the need to acid-digest the frozen samples before analysis as a means to push all particulate matter into solution. No significant results can be contributed to the data records on Lake Auburn from this study. In addition, historical data was analyzed for patterns of hypolimnetic hypoxia and the correlation to TP. In general the historical data, ranging from 1999 to 2016, shows that following the worst lake conditions in 2012 and 2013 the lake was able to improve in 2014 and 2015, before worsening in 2016. Further analysis of water samples for TP should focus on the spectrophotometric method, and further data analysis should look at the co-limitation of nitrogen.

Components of Thesis

1 pdf file

Restricted

Available to Bates community via local IP address or Bates login.

Share

COinS