Abstract


LEGACY DISTURBANCE EFFECTS IN A LAKE LITTORAL ZONE: EFFECTS OF STAMP SANDS ON STRUCTURE MACROPHYTE COMMUNITIES IN THE KEWEENAW WATERWAY OF MI (S)

Large-scale disturbances can cause legacy effects on community structure and invasibility in lake littoral zones. We compared macrophyte community structure of littoral habitat disturbed by heavy metal-rich mining residues (hereafter stamp sands) deposited from 1868-1910 relative to habitat with native sediments in the Keweenaw Waterway of Michigan. Stamp sand deposits were mostly devoid of macrophytes; however, when present total macrophyte biomass, diversity, species richness, and coefficient of conservatism did not significantly differ between sites types. At the taxonomic level, Vallisneria americana was the most common macrophyte observed and 1/2 as dense at stamp sand sites. Potamogeton richardsonii and Potamogeton gramineus were 5.3 and 6.4 times denser at non-stamp sand sites. Non-native Myriophyllum spicatum was only found at stamp sand sites, while hybrid M. spicatum x M. sibricum was found at both site types, but was 7.2 times denser at non-stamp sand sites. Our results suggest that legacy disturbance may alter littoral macrophyte species composition and promote the invasion of non-native species. We are working to determine the relative roles of sediment chemistry, heavy metals, and texture on these dynamics.

Authors

Van Goethem, R. R., Michigan Technological University, USA, rrvangoe@mtu.edu

Marcarelli, A. M., Michigan Technological University, USA, ammarcar@mtu.edu

Juneau, K. J., University of Wisconsin-River Falls, USA, kjjuneau@mtu.edu

Huckins, C. J., Michigan Technological University, USA, cjhuckin@mtu.edu

Details

Poster presentation

Session #:CS10
Date: 06/07/2016
Time: 17:30 - 19:00
Location: Poster/Exhibit Hall

Presentation is given by student: Yes

PosterID: 48