The CALS Research Honors Abstracts is printed annually each summer by the Office of Academic Programs (OAP) to recognize students and their faculty mentors in research. In order to be included in this publication, students must provide the following information electronically to their Research Honors Program area chair:
- Title of research thesis
- Student’s name (first, middle initial, last)
- "Under the supervision of [name of faculty mentor]"
- Department in which research was performed (same as faculty mentor's department)
- Thesis abstract, not to exceed 250 words.
- Address to which the booklet can be mailed to the student (booklets are mailed the following fall).
When writing an abstract, students should follow the format in the example below. Students who fail to provide the information requested above will not be featured in the booklet.
After the publication is printed, OAP will send a copy to each honors student that provided a mailing address. The publication may also be viewed online.
The Effects of Freezing and Winter Temperature Conditions of Three Alpine Lakes on Macroinvertebrate Community Composition
Gavin J. Svenson
Under the supervision of Barbara L. Peckarsky
Department of Entomology
To persist in alpine lakes, populations must be able to withstand extreme winter temperatures (freezing) and annual thermal variability. Although challenging to obtain, direct measurements of winter conditions and comparisons of macroinvertebrates in alpine lakes before, during and after lake freezing can provide insights into effects of different freezing patterns on community composition. In this study comparisons were made of the physical characteristics, thermal regimes, macroinvertebrate species diversity, and abundances among three alpine lakes located in the White Mountains, NH, during October, January and June 2000-2001. Two of the lakes (Upper Lake of the Clouds and Star Lake) froze solid for about a third of the year, while some areas of substrate in the third lake (Lower Lake of the Clouds) never reached temperatures below zero, thereby providing refuges from freezing for benthic invertebrates. Species diversity (richness and evenness) was greatest in Lower Lake, but invertebrate abundance was also low, possibly because this lake had fewer cumulative degree-days above zero (a shorter growing season) than either Upper Lake or Star Lake. While total benthic macroinvertebrate densities did not differ significantly among the three lakes, individual taxa were influenced differently by winter conditions seen the study lakes. The invertebrate fauna of all three lakes was dominated by the dipteran family Chironomidae, some species of which are known to have evolved the ability to overwinter in frozen benthic substrates. Species in the subfamily Chironominae (especially Chironomus spp.) and Tanypodinae were common in the most extreme lakes; while Orthocladiinae were most common in the lake that did not freeze solid. These taxa often predominate in alpine and arctic aquatic systems, and can serve as indicators of extreme winter conditions.