Structure and Function of Great Lakes Coastal Wetlands

Doctoral Dissertation
Thumbnail

Abstract

Coastal wetlands occur throughout the Laurentian Great Lakes where hydrology and sediment are conducive to macrophyte growth. These shallow, productive ecosystems have diverse emergent and submergent vegetation that provides critical habitat for many species of fish, birds, mammals, reptiles, and amphibians. Unfortunately, approximately half of the coastal wetland area that was present before European settlement has been converted to other land uses and the majority of remaining wetlands are impacted to varying degrees by invasive species, fragmentation, nutrient loading, and hydrologic manipulation. Consequently, coastal wetland protection and restoration are vital components of a longā€term management strategy for the Great Lakes. For protection and restoration to be effective, however, a better understanding of coastal wetland structure and function and improved monitoring tools are needed. In my research, I found that watershed and surrounding land cover, especially agriculture, impacted coastal wetland water quality by increasing nutrient concentrations, conductivity, and turbidity. Using nutrient-diffusing substrata, I found that algal biomass accrual was frequently nitrogen-limited and rarely phosphorus-limited, suggesting that nitrogen loading from agricultural lands and other sources has the potential to stimulate excessive algal growth and affect ecosystem function in Great Lakes coastal wetlands. I also documented water quality impairment and altered land cover to be associated with structural changes to algal, macroinvertebrate, and fish communities, illustrating the far-reaching impacts of anthropogenic disturbance on coastal wetland ecosystems. Macroinvertebrate community structure was also related to natural drivers including hydrologic energy and water levels. I used my findings related to abiotic conditions and community structure to develop a fish-based index of biotic integrity and an abiotic index of wetland conditions for use in monitoring. These tools will help ecosystem managers to track wetland conditions and to prioritize protection and restoration investments across the Great Lakes basin. Furthermore, given that these anthropogenic stressors and natural drivers are not unique to the Great Lakes, my findings and related indices are applicable to other coastal ecosystems.

Attributes

Attribute NameValues
URN
  • etd-08152014-000054

Author Matthew J Cooper
Advisor Gary Lamberti
Contributor Stuart Jones, Committee Member
Contributor Gary Lamberti, Committee Chair
Contributor Donald Uzarski, Committee Member
Contributor Jennifer Tank, Committee Member
Degree Level Doctoral Dissertation
Degree Discipline Biological Sciences
Degree Name PhD
Defense Date
  • 2014-08-06

Submission Date 2014-08-15
Country
  • United States of America

Subject
  • index of biotic integrity

  • macroinvertebrate

  • nutrient limitation

  • community structure

Publisher
  • University of Notre Dame

Language
  • English

Record Visibility and Access Public
Content License
  • All rights reserved

Departments and Units

Files

Please Note: You may encounter a delay before a download begins. Large or infrequently accessed files can take several minutes to retrieve from our archival storage system.