HOME > Publications > Theses & Dissertations > Thesis & Dissertations abstracts

Thesis Abstract – Goeldner (1979)


The Effect of Enrichment on Phytoplankton Communities Within Bernard Field Station Lake

Author and college:

Jo L. Goeldner


May 4, 1979


Bachelor of Arts in Biology




This thesis has a two-fold purpose. First, because the Bernard Field Station Lake was recently filled, it provides the opportunity of a long term study of the eutrophication process. Some physical and chemical parameters of the lake were monitored for the first eight months of the lake’s existence. Bernard Field Station Lake is a small reservoir quite susceptible to eutrophication. The lake has no effluent flow and an expected high rate of evaporation in the summer and will presumably act as a sink for collecting nutrients. I hypothesize that eutrophication will proceed rapidly. &dlquo;Rapidly” covers a span of several years beyond the term of this study, so the second purpose of this study was to enrich several phytoplankton microcommunities with various concentrations of nitrates and orthophosphates to determine the limiting factor for phytoplankton growth. It was found that nitrates in large quantities and orthophosphates in small quantities resulted in a high growth rate. Considering the surrounding soil is deficient in nitrogen and high in phosphorus, it is likely that nitrogen acts as the liming factor for phytoplankton growth in this ecosystem. The high internal orthophosphate concentration may be supplemented by runoff from the surrounding phosphorus rich soil. The lake will undoubtedly remain productive and increase productivity as time passes.

For more information:

Contact Velda Ross – vross@kecksci.claremont.edu

© 2001-2015 Bernard Field Station Faculty Advisory Committee
Page last updated 21 May 2012 by Nancy Hamlett.