Defense Date

2009

Document Type

Thesis

Degree Name

Master of Science

Department

Environmental Studies

First Advisor

Dr. Leonard A. Smock

Abstract

The purpose of this study was to determine if the complexity and surface area of a macrophyte’s

structure has an influence on invertebrate colonization, and to determine the influence of two non-native species on invertebrate colonization. Three plant architectures were compared. Floating leaved plants were represented by the following species: Nuphar lutea, Nymphaea odorata, and Brasenia schreberi. Moderately dissected leaved plants were represented by Potamogeton natans, and highly dissected leaved plants were represented by two non-native species, Myriophyllum spicatum and Myriophyllum heterophyllum. The number of invertebrates/g dry biomass and the number of individuals/m², diversity, evenness, and richness were calculated for comparison. The density of invertebrates was significantly different among the different plant architecture types for both individuals per m² and individuals per/g dry biomass (ANOVA, F=33.53, p < 0.0001; ANOVA, F=194.41, p < 0.0001). The highly dissected milfoils had the greatest density of individuals per gram dry plant biomass compared to the moderately dissected plants, and the moderately dissected plants had a greater density of individuals per gram dry mass than floating leaved plant. There were also differences in terms of invertebrate community diversity (H'), (ANOVA, F=l7.08, p < 0.001), and richness (ANOVA, F= 35.52, p < 0.001), but not evenness (ANOVA, F = 1.83, p = .0961). When the number of invertebrates/g dry plant biomass was examined in lakes where the highly dissected plants were ”rare/not observed", there was a lower density of invertebrates per gram dry biomass. This was significantly lower than in lakes where the highly dissected plants were both ”common” and ”dominant” (ANOVA, F=3.31, p = 0.0393). Data analysis was strongly affected by the density of the oligochaete Sty/aria and the amphipod Hyallela azteca, as evident in the Principle Component Analysis. Parameters associated with the two axes, principle component 1 and principle component 2, explained 86% of the variation in epiphytic invertebrate density.

Comments

Scanned, with permission from the author, from the original print version, which resides in University Archives.

Rights

© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

10-1-2018

Included in

Life Sciences Commons

Share

COinS