Physical Sciences and Mathematics Commons^™

Evidence Of Climate Variability And Tropical Cyclone Activity From Diatom Assemblage Dynamics In Coastal Southwest Florida, Emily R. Nodine

FIU Electronic Theses and Dissertations

Estuaries are dynamic on many spatial and temporal scales. Distinguishing effects of unpredictable events from cyclical patterns can be challenging but important to predict the influence of press and pulse drivers in the face of climate change. Diatom assemblages respond rapidly to changing environmental conditions and characterize change on multiple time scales. The goals of this research were to 1) characterize diatom assemblages in the Charlotte Harbor watershed, their relationships with water quality parameters, and how they change in response to climate; and 2) use assemblages in sediment cores to interpret past climate changes and tropical cyclone activity.

Diatom assemblages …

Habitat Use Of The Key Largo Woodrat (Neotoma Floridana Smalli), Lauren J. Barth

FIU Electronic Theses and Dissertations

Key Largo woodrats are an endangered subspecies with an extremely limited habitat. This study sought to understand woodrat habitat preferences in order to guide management. Woodrats build stick nests from natural and artificial materials, so nest distribution and nest occupancy were used as indicators of preference. Distribution was determined by nest surveys, and remote cameras were used to assess occupancy. Forest structure, human disturbance, nest, and animal presence metrics were also collected. More nests were found along abandoned roads than along forest transects and more artificial nests were occupied than natural nests. These findings indicate that woodrats prefer areas with …

Spatio-Temporal Analysis Of Chilling Events In Mangrove Forests Of South Florida, Bina Thapa

FIU Electronic Theses and Dissertations

Chilling events are infrequent but important disturbances in subtropical Florida. When temperatures drop to near freezing, significant mortality often accrues in mangrove forests. Chilling events play a role in maintaining structural diversity in mangrove forests, and in limiting mangrove poleward distribution. I examined the spatio-temporal distribution of chilling events in mangrove forests of southern Biscayne Bay by using Landsat TM5 images since 1989. Damage was usually confined to dwarf mangrove forest, especially when chilling temperatures were moderate and short in duration. However, damage from extended and severe freezes such as in January 2010 impacted larger trees as well. Recovery is …

Characterization Of Rhizobial Diversity And Relationship Of Rhizobial Partner And Legume Performance In Four South Florida Pine Rockland Soils, Vanessa Sánchez

FIU Electronic Theses and Dissertations

Pine rocklands are endangered ecosystems unique to south Florida, the Bahamas and Cuba. As a result of their karstic calcium carbonate­rich soil, these systems are limited in phosphorus and nitrogen, making symbiotic associations critical to plant growth. Four leguminous species (Cajanus cajan, Chamaecrista fasciculata, Tephrosia angustissima, and Abrus precatorious) were used to determine the relationship between rhizobial partners and plant performance, and the symbiosis related gene nifH was amplified to characterize the diversity of rhizobial symbionts. Plants were grown in soils from four different south Florida pine rocklands, and a salinity treatment was added to determine …