Life Sciences Commons^™

Reproductive Ecology And Phenology Of Thalassia Testudinum (Hydrocharitaceae) In Tampa Bay, Florida, Sheila Scolaro

USF Tampa Graduate Theses and Dissertations

Successful sexual reproduction and recolonization are critical in maintaining genetic diversity within seagrass meadows. Thalassia testudinum flower, fruit and seedling production were assessed visually at 10 sites within Tampa Bay, Florida approximately every 4 weeks from May to July 2017 to determine if there is spatial and temporal variation in sexual reproductive effort and if location within a meadow effects sexual reproductive effort. Results from this study reveal strong temporal variability throughout the reproductive season. The month of May was observed as peak Thalassia testudinum anthesis and June was peak fruiting in Tampa Bay during 2017. Flower and fruit density …

Measuring Flowering Phenology And Its Consequences: A Systematic Review, Samantha M. Mangum

USF Tampa Graduate Theses and Dissertations

Despite growing interest in flowering phenology among ecologists, as reflected by an increase in the number of papers, there is little information on how studies typically measure and describe a plant’s flowering phenology. The focus of this study was the literature on flowering phenology and the approaches researchers have taken to quantify flowering phenology. Initially, a comprehensive description of the breath of literature on flowering phenology was produced. From there, I described the current research on flowering phenology: the year that the studies were published, the locations of the studies, and the particular biomes where the studies were performed. The …

The Archaeopalynology Of Crystal River Site (8ci1), Citrus County, Florida, Kendal Jackson

USF Tampa Graduate Theses and Dissertations

The Woodland-period (ca. 1000 B.C. to A.D. 1050) fisher-hunter-gatherers of the Crystal River drainage on Florida’s Big Bend Coast are well known among southeastern archaeologists for their elaborate shell mound architecture, maritime lifeway, and exotic exchange goods. Recent archaeological investigations at the Crystal River site have employed high-resolution topographic mapping, geophysical surveys, trench excavations, and coring to model the temporality of mound construction and occupation at the site; this work has set the stage for subsequent research focusing on community structure, resource extraction, and human-ecosystem dynamics. However, like many central and north peninsular Gulf Coast sites, our understanding of Crystal …

Water Availability As The Driving Factor Of Growth And Physiological Function Of Co-Occurring Scrub Species In Central Florida, Tammy Foster

USF Tampa Graduate Theses and Dissertations

Florida scrub is a xeromorphic upland shrub community dominated by evergreen oaks that resprout after fire, occurring on moderately to excessively well-drained nutrient-poor sand. Scrub is home to several threatened and endangered animal species (e.g., Florida scrub-jay, gopher tortoise, and indigo snake) and rare and endemic plants. Urban development and agriculture has greatly reduced and fragmented scrub habitat, and because of this Florida scrub is considered one of the most endangered ecosystems in the United States. Climate change is a further threat to Florida scrub. Under a warmer and drier climate, scrub species will be exposed to more frequent and …

Chlorophyll Fluorescence And Thermal Stress In Archaias Angulatus (Class Foraminifera), Heidi M. Toomey

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Benthic foraminifers that host algal symbionts are similar to corals in that they rely on their algal endosymbionts for their energy needs, calcify prolifically, and are sensitive to changes in environmental conditions. They are abundant in the benthos of coastal coral-reef areas and are found throughout the tropical and subtropical regions. Pulse Amplitude Modulated (PAM) chlorophyll fluorometry and chlorophyll a extraction techniques were used to quantify and compare the photosynthetic responses of the benthic foraminiferal, Archaias angulatus and their isolated endosymbionts, Chlamydomonas hedleyi, to short-term changes in temperature. Maximum quantum efficiency (F_v/F_m) and rapid …

An Investigation Of The Factors Leading To Invasion Success Of Non-Native Plants Using A System Of Native, Introduced Non-Invasive, And Invasive Eugenia Congeners In Florida, Kerry Bohl

USF Tampa Graduate Theses and Dissertations

The overwhelming majority of plant species introduced into a new range never become invasive. Consequently, identification of factors allowing the small fraction of successful invaders to naturalize, increase in abundance, and displace resident species continues to be a key area of research in invasion biology. Of the considerable number of hypotheses that have been proposed to resolve why some plant species become noxious pests, the enemy release hypothesis (ERH) is one of the most commonly cited. The ERH maintains that invasive plants succeed in a new range because they are no longer regulated by their coevolved natural enemies, and this …

Heterogeneous Stress Response In A Clonal Invader (Imperata Cylindrica): Implications For Management, Sarah Grace Sanford

USF Tampa Graduate Theses and Dissertations

Life history traits such as growth, survival, and clonality can vary within a population. When such variation exists in a population of an invasive species, it can affect population dynamics, and if any part of the variation has a genetic basis the population can evolve in response to control regimes. Evolutionary responses to control efforts may shift the population towards a few more resilient genotypes, or towards different types in different microenvironments, depending on the scale of gene flow with respect to the patchiness of the environment. The purpose of this study is to examine whether the application of stress …