In plants, phenotypic plasticity, the ability to morphologically adapt to new or broad environmental conditions, is a consequence of long-term evolutionary genetic processes. Thus, plants adapted to low phosphate (P) environments exhibit only limited plasticity to take advantage of nutrient enrichment, a global phenomenon in terrestrial and aquatic environments. In the face of anthropogenic P-enrichment, low nutrient adapted resident plant species are frequently displaced by species with high morphological and genetic plasticity. However, it remains unclear whether plasticity is systemically expressed across molecular, biochemical, physiological, and morphological processes that ultimately contribute to the root and shoot phenotypes of plants. In this study, we demonstrated high plasticity in root-borne traits of sawgrass (Cladium jamaicense), the dominant plant species of the P-impoverished Everglades, and counter the idea of inflexibility in low P adapted species. However, sawgras s expressed inflexibility in processes contributing to shoot phenotypes, in contrast to cattail, which was highly plastic in shoot characteristics vii in response to P enrichment. In fact, plasticity in cattail shoots is likely a function of its growth response to P that was globally regulated by P-availability at the level of transcription. Plasticity and inflexibility in the growth of both species also diverged in their allocation of P to the chloroplast for growth in cattail versus the vacuole for P storage in sawgrass. In the Everglades, anthropogenic P-enrichment has changed the environment from a P-limited condition, where plasticity in root-borne traits of sawgrass was advantageous, to one of light-competition, where plasticity in shoot-borne traits drives competitive dominance by cattail. / We hypothesize that these shifts in plasticity competitive advantage from root to shoots has been a major driver of cattail expansion in the Everglades ecosystem. Further, this understanding of how natural plant species adapt and shift in response to nutrient availability could also be used a model system to optimize agricultural systems to increase efficiencies in food production and protect low nutrient adapted natural systems from cultural eutrophication. / by James Webb. / Vita. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 200?. Mode of access: World Wide Web.

The Florida Fish and Wildlife Conservation Commission lacks a viable method for monitoring woody vegetation in expansive wetland communities, such as the Florida Everglades. This study used aerial photographs of Rotenberger Wildlife Management Area in southeastern Palm Beach County, Florida to develop techniques for remotely monitoring changes in woody vegetation. Imagery from 2006, 2008, and 2010 were classified into woody and non-woody categories using Adobe Photoshop's Magic Wand Tool. Selection was performed with a bias toward over classification, as project objectives required identifying as many trees as possible. Classified pixels in Time 1 within 4 feet (2 pixels) of classified pixels from Time 2 were considered the same canopy. Overall accuracy for the study was 98%. / by Sarah Franklin. / Thesis (M.A.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.

Loggerhead (Caretta caretta) and green (Chelonia mydas) turtles recruit to nearshore environments as juveniles. These often degraded habitats are associated with emerging diseases such as green turtle fibropapillomatosis (GTFP), however there are few studies on immune function in sea turtles. The objective of this research was to quantify phagocytosis of the innate immune system by flow cytometry and compare levels between animals from a degraded habitat (the Indian River Lagoon, FL) to a more pristine environment (the Trident Basin, Port Canaveral, FL), and across a range of temperatures. While in vitro temperatures did not alter rates of phagocytosis, it was higher in samples obtained in the summer than winter. Rates of phagocytosis in sea turtles with GTFP and from degraded environments with increased prevalence of GTFP were low compared to animals from the more pristine environment, suggesting that the environment can alter innate immunological function and thus contribute to the development of disease. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

In the Florida Everglades, sawgrass has been displaced by cattail, predominantly resulting from phosphate enrichment. It has been found that phosphate transporters and arbuscular mycorrhizal (AM) fungi play an important role in phosphate uptake in the plants. This study aimed to reveal the symbiosis between AM fungi and sawgrass and cattail and identify the phosphate transporters, especially AM-specific phosphate transporters in these two species. AM colonization was only found in sawgrass roots, not cattail, at low phosphate concentrations in lab and field samples by trypan blue staining. AM fungi could increase sawgrass growth and had little effect on cattail growth. Four phosphate transporters were identified in sawgrass. CjPT1, CjPT2 and CjPT3 were expressed in roots and shoots independent of AM fungi and phosphate availability, while CjPT4 appeared to be an AM regulated phosphate transporter gene and its expression was induced by AM fungi. / by Li Lin. / Thesis (M.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Pixel based and object based vegetation community classification methods were performed using 30 meter spatial resolution Landsat satellite imagery of the Arthur R. Marshall Loxahatchee National Wildlife Refuge (Refuge), a remnant of the northern Everglades. Supervised classification procedures using maximum likelihood and parallelepiped algorithms were used to produce thematic maps with the following vegetation communities : wet prairie, sawgrass, cattail, tree island, brush, aquatic/open water. Spectral data, as well as NDVI, texture and principal component data were used to produce vegetation community classification maps. The accuracy levels of the thematic maps produced were calculated and compared to one another. The pixel based approach using the parallelepiped classification algorithm on the spectral and NDVI dataset had the highest accuracy level. A generalized form of this classification using only three vegetation communities (all wet prairie, tree island/brush and aquatic/open water) was compared to a previously published classification which used 1987 SPOT imagery in order to extract information on possible vegetation community transitions that are occurring within the Refuge. Results of the study indicate that 30 meter spatial resolution may be useful for understanding broad vegetation community trends but not species level trends. Pixel based procedures provide a more accurate classification than object based procedures for this landscape when using 30 meter imagery. Lastly, since 1987 there may be a trend of tree island/brush communities replacing wet prairie communities in the northern part of the Refuge and a transition to wet prairie communities in place of tree island/brush communities in the southern portion of the Refuge. / by Dorianne M. Barone. / Thesis (M.S.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, FL : 2008 Mode of access: World Wide Web.

The study examined the past and present spatial distribution of the Florida tree snail, L. fasciatus solidus, in the Long Pine Key area of the Everglades National Park. Remote sensing and mobile GIS were used to create a GIS database of the field research results. Collection and survey-based data were used to create a current spatial distribution map of L. fasciatus solidus throughout the Long Pine Key area. The data collected during the 2006 survey were compared to a 1931 survey of the same study area conducted by Dr. William Clench of the Museum of Comparative Zoology (MCZ) of Harvard University. The data was used to determine the success of L. fasciatus solidus from 1931 to 2006, to evaluate a correlation between hammock size and the number of color forms, and to detect migration patterns of L. fasciatus solidus within the Long Pine Key area of Everglades National Park. Based on the average success rate for the seven color forms and the hammocks, the L. fasciatus solidus population in the Long Pine Key area exemplifies one of a stable community. Each color form used for the analysis had a success rate between 67% and 100%. These percentages can only be the worst case scenario based on the fact that many Liguus were not observed, and any others that would have been observed, would only increase the success rate. / by Jason R. Fadely. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

In estuaries, like the Indian River Lagoon, mesozooplankton have a vital role in the food web by connecting trophic levels. In this study, mesozooplankton abundance and species composition were monitored weekly on the incoming and outgoing tides from September 2006 to May 2009. For the incoming tide, the mean abundance was 2298.2 mesozooplankton/m3 (+/-325.2), and for the outgoing tide the mean abundance was 1180.0 mesozooplankton/m3 (+/-153.1). The mesozooplankton abundance on the incoming tide was significantly greater than on the outgoing tide. The most abundant type of mesozooplankton was the copepod Acartia tonsa, representing 35.0% and 52.1% of the individuals on the incoming and outgoing tides respectively. Mesozooplankton abundance values were compared with environmental data obtained from the South Florida Water Management District. The strongest positive correlation was found between chlorophyll a concentrations and A. tonsa abundance, likely due to phytoplankton being the primary food source for A. tonsa. / by Miranda Hoover Kerr. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

Fire plays a key role in the ecology of the Everglades and is a ubiquitous tool for managing the structure, function, and ecosystem services of the Greater Everglades watershed. Decades of hydrologic modifications have led to the alteration of plant community composition and fire regime in much of the Everglades. To create a better understanding of post-fire recovery in sawgrass (Cladium jamaicense) communities, sawgrass marshes in the northern Everglades were studied along a chronosequence of time since fire and along a nutrient gradient. Areas closer to a water nutrient source and with fewer mean days dry contained greater total and dead aboveground graminoid biomass whereas live graminoid biomass was greater in areas with less time since fire and with fewer days dry. Post-fire characteristics of sawgrass marshes can provide insight on the effectiveness of fire management practices in the maintenance and restoration of quality habitat in the northern Everglades. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

As ecosystems degrade globally, ecosystem services that support life are increasingly threatened. Indications of degradation are occurring in the Northern Indian River Lagoon (IRL) estuary in east central Florida. Factors associated with ecosystem degradation are complex, including climate and land use change. Ecosystem research needs identified by the Millennium Ecosystem Assessment (MA) include the need to: consider the social with the physical; account for dynamism and change; account for complexity; address issues of scale; and focus on ecosystem structure and process. Ecosystems are complex, self-organizing, multi-equilibrial, non-linear, middle-number systems that exist in multiple stable states. Results found are relative to the observation and the frame of analysis, requiring multi-scaled analytical techniques. This study addresses the identified ecosystem research needs and the complexity of the associated factors given these additional constraints. Relativity is addressed through univariate analysis of dissolved oxygen as a measure of the general health of the Northern IRL. Multiple spatial levels are employed to associate social process scales with physical process scales as basin, sub-basins, and watersheds. Scan statistics return extreme value clusters in space-time. Wavelet transforms decompose time-scales of cyclical data using varying window sizes to locate change in process scales in space over time. Wavelet transform comparative methods cluster temporal process scales across space. Combined these methods describe the space-time structure of process scales in a complex ecosystem relative to the variable examined, where the highly localized results allow for connection to unexamined variables. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

In Florida, mangroves have responded to climate change by slowly migrating northward into traditional salt marsh habitat. However, little is understood about the relationships among mangrove growth form plasticity and environmental conditions. In addition, the effects of the mangrove northward expansion on pre-existing salt marsh communities are unknown, especially any influences of differences in tree morphology. The size, canopy structure, and root structure of the three mangrove species Rhizophora mangle, Avicennia germinans, and Laguncularia racemosa were measured at six sites along the east coast of Florida. Structural equation modeling was used to evaluate the multivariate relationships between environmental and biotic variables. Mangrove growth form varied widely with environmental variables. The results of this study suggest that R. mangle expansion into salt marsh may rely on interactions with salt marsh and shading as well as on climatic variables, which has implications for future mangrove expansion northward in Florida. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection