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Influence Of Soil Biogeochemical Properties On The Invasiveness Of Old World Climbing Fern (Lygodium Microphyllum), Pushpa Gautam Soti Oct 2013

Influence Of Soil Biogeochemical Properties On The Invasiveness Of Old World Climbing Fern (Lygodium Microphyllum), Pushpa Gautam Soti

FIU Electronic Theses and Dissertations

The state of Florida has one of the most severe exotic species invasion problems in the United States, but little is known about their influence on soil biogeochemistry. My dissertation research includes a cross-continental field study in Australia, Florida, and greenhouse and growth chamber experiments, focused on the soil-plant interactions of one of the most problematic weeds introduced in south Florida, Lygodium microphyllum (Old World climbing fern). Analysis of field samples from the ferns introduced and their native range indicate that L microphyllum is highly dependent on arbuscular mycorrhizal fungi (AMF) for phosphorus uptake and biomass accumulation. Relationship with AMF …


The Effect Of Contemporary Hydrologic Modification On Vegetation Community Composition Distinctness In The Florida Everglades, Ewan Isherwood Oct 2013

The Effect Of Contemporary Hydrologic Modification On Vegetation Community Composition Distinctness In The Florida Everglades, Ewan Isherwood

FIU Electronic Theses and Dissertations

The historic Everglades Ridge and Slough landscape maintained regularly spaced and elevated sawgrass ridges interspersed among exposed deeper-water sloughs; however, widespread but irregular hydrologic modification has degraded much of this landscape patterning. My study assessed the effects of hydrologic modification on vegetation community distinctness within the Ridge and Slough landscape through sampling species composition at fine-scales along a hydrologic gradient to measure the magnitude of segregation of species among patch types. The results show that vegetation community and topographic variation degradation is widespread, with distinctness differences proceeding and possibly being driven by topographic variation loss. Vegetation responses to past hydrologic …


Genetic Structure Of The Florida Key Tree Cactus, Pilosocereus Robinii, Using Restriction Site Associated Dna (Rad) Markers, Tonya D. Fotinos Jul 2013

Genetic Structure Of The Florida Key Tree Cactus, Pilosocereus Robinii, Using Restriction Site Associated Dna (Rad) Markers, Tonya D. Fotinos

FIU Electronic Theses and Dissertations

Rare plant conservation efforts must utilize current genetic methods to ensure the evolutionary potential of populations is preserved. One such effort involves the Key Tree Cactus, Pilosocereus robinii, which is an endangered columnar cactus native to the Florida Keys. The populations have precipitously declined over the past decade because of habitat loss and increasing soil salinity from rising sea levels and storm surge. Next-generation DNA sequencing was used to assess the genetic structure of the populations. Twenty individuals representative of both wild and extirpated cacti were chosen for Restriction Site Associated DNA (RAD) analysis. Samples processed using the HindIII …


The Effects Of Arbuscular Mycorrhizal Fungi On Four Legume Hosts In South Florida Pine Rockland Soils, Klara Scharnagl Jul 2013

The Effects Of Arbuscular Mycorrhizal Fungi On Four Legume Hosts In South Florida Pine Rockland Soils, Klara Scharnagl

FIU Electronic Theses and Dissertations

This study addressed the effects of salinity and pot size on the interaction between leguminous plant hosts and arbuscular mycorrhizal fungi in four pine rockland soils using a shade house trap-plant experiment. Little is known about the belowground diversity of pine rocklands and the interactions between aboveground and belowground biota – an increased understanding of these interactions could lead to improved land management decisions, conservation and restoration efforts. Following twelve weeks of growth, plants were measured for root and shoot dry biomass and percent colonization by arbuscular mycorrhizal fungi. Overall, arbuscular mycorrhizal fungi had positive fitness effects on the four …


Buckwheat As A Cover Crop In Florida: Mycorrhizal Status, Soil Analysis, And Economic Assessment, Daria Boglaienko Jul 2013

Buckwheat As A Cover Crop In Florida: Mycorrhizal Status, Soil Analysis, And Economic Assessment, Daria Boglaienko

FIU Electronic Theses and Dissertations

This thesis analyses buckwheat as a cover crop in Florida. The study was designed to demonstrate: soil enrichment with nutrients, mycorrhizal arbuscular fungi interactions, growth in different soil types, temperature limitations in Florida, and economic benefits for farmers. Buckwheat was planted at the FIU organic garden (Miami, FL) in early November and harvested in middle December. After incorporation of buckwheat residues, soil analyses indicated the ability of buckwheat to enrich soil with major nutrients, in particular, phosphorus. Symbiosis with arbuscular mycorrhizal fungi increased inorganic phosphorus uptake and plant growth. Regression analysis on aboveground buckwheat biomass weight and soil characteristics showed …


Effects Of Multiple Ecological Drivers On Recruitment And Succession Of Coral Reef Macroalgal Communities, Alain Duran Jun 2013

Effects Of Multiple Ecological Drivers On Recruitment And Succession Of Coral Reef Macroalgal Communities, Alain Duran

FIU Electronic Theses and Dissertations

The study evaluated the effects of herbivory pressure, nutrient availability and potential propagule supply on recruitment and succession of coral reef macroalgal communities. Recruitment and succession tiles were placed in a nutrient-herbivory factorial experiment and macroalgal abundances were evaluated through time. Proportional abundances of macroalgal form-functional groups on recruitment and succession tiles were similar to field established communities within treatments, evidencing possible effects of adult macroalgae as propagule supply. Macroalgal abundance of recruitment tiles increased with nutrient loading and herbivory reduction combined whereas on succession tiles nutrient loading increased abundance of articulated-calcareous only when herbivores were excluded. Macroalgal field established …