USF St. Petersburg campus Master's Theses (Graduate)

First Advisor

Major Professor: Deby Cassill, Ph.D

Second Advisor

James Bays, MS

Third Advisor

Thomas J. Whitmore, Ph.D


University of South Florida St. Petersburg

Document Type


Publication Date


Date Issued

September 13, 2019


In Florida, urban lakes are challenged. Pollution from surrounding urban ecosystems is detrimental to the ecological health of these lakes. Planting and restoring native wetlands along the littoral zone of these lakes will reduce the effects of pollution. Crescent Lake is an urban lake in Pinellas County, Florida, USA, that has recently begun to restore its wetlands system. This study surveys and evaluates the plant species in the wetland, shoreline, and parkland habitats of Crescent Lake to determine the effectiveness of management. Transects and quadrats were used to determine the diversity and structure of native and non-native plant species. 58 plant species were recorded in the survey, with 40 species identified. Native species had more occurrences than non-native species. The average proportional coverage for all species across all habitats was 30%. The parkland habitat had the highest diversity in this study. Native and non-native species had similar proportions of coverage for all habitats. Non-native species had lower diversity than native species. Stenotaphrum secundatum (Walter) Kuntze (St. Augustine grass), and Colocasia esculenta (L.) Schott (wild taro) had the highest total counts while Sphagneticola trilobata (L.) Pruski (wedelia), Brachiaria mutica (Forssk.) T.Q.Nguyen (para grass), and S. secundatum had the most occurrences of greater than 99% coverage within a quadrat. Each species will require different management techniques for control. Past conservation efforts have been effective in returning the wetlands, lost from decades earlier, to Crescent Lake. However, more restoration work and ecological studies are needed to ensure the continued viability of the wetland plants in the littoral zone. Maintaining these restored wetlands will ensure the continuation of their benefits to the ecological health of the lake. A diverse wetland ecosystem is more resistant to the pressures of pollution and non-native invasion.


A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science Department of Conservation Biology College of Arts & Science University of South Florida, St. Petersburg

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Creative Commons License
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