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Interaction Of Rhizobium Sp. Strain Irbg74 With A Legume (Sesbania Cannabina) And A Cereal (Oryza Sativa), Shubhajit Mitra

Theses and Dissertations

Rhizobium sp. IRBG74 (IRBG74) develops a classical nitrogen-fixing symbiosis with the legume Sesbania cannabina and also promotes the growth of rice (Oryza sativa), but not much is known about the rhizobial determinants important for these interactions. We hypothesize that Rhizobium sp. IRBG74 utilizes similar mechanisms to endophytically colonize both legume and cereal hosts. In this study, we analyzed the colonization of rice and S. cannabina using a strain of IRBG74 marked with β-glucuronidase (GUS) and Green Fluorescent Protein (GFP). IRBG74 infected both of the host plants through crack entry under submerged conditions, but showed root hair mediated infection under aerobic …

Influences Of Yard Management Intensity On Urban Soil Biogeochemistry, Viviana Penuela Useche

USF Tampa Graduate Theses and Dissertations

Soils are critical to ecosystem function as they provide essential nutrients for primary producers, habitat and organic energy for decomposers, and storage of organic matter. Irrigation with reclaimed water is an increasingly popular water conservation strategy; yet its high salinity and nutrient content potentially affect soil properties. In this study, set in a residential neighborhood of Tampa (U.S.). I tested whether there are distinct lawn system management strategies characterized by systematic differences in reclaimed water usage and irrigation and fertilization practices. I then investigated whether soil biogeochemistry responds to lawn system management strategy.

My results indicated that amendment strategy, which …

Wetland Sediment Nutrient Flux In Response To Proposed Hydrologic Reconnection And Climate Warming, James T. Smit

Masters Theses

Wetland restoration and creation are common practices, but wetlands restored or created on former agricultural land may act as a source of nutrients, rather than as a sink. I studied P sediment-water exchange in two flooded celery fields (west and east), which are designated for wetland restoration, in order to assess the effects that hydrologic reconnection of the area to an adjacent creek would have on P dynamics. We also examined the influence of climate change, specifically warming temperatures, by conducting the sediment-water exchange experiments at ambient and plus 2°C temperature conditions. Lab-based sediment core incubations revealed that TP release …

Water Water Everywhere: Analyzing Long Island's Water Issues And Finding Solutions For A Sustainable Future, Anthony T. Becker

2014 Student Theses

Over three million people call Long Island their home. With access to beautiful landscapes, world-renowned beaches, and proximity to New York City, it is no wonder that so many proudly call this geographic stretch of glacial till their home. However, throughout the years our actions do not necessarily reflect this affection we have to our home. Years of sprawl and human infestation across the island have resulted in widespread environmental degradation. Specifically, the water we drink and the beaches we enjoy have become endangered. I plan on studying the urban ecology of how intensified population growth led to the eutrophication …

The Effects Of Substituting True Protein With Non-Protein Nitrogen In Holstein Dairy Heifers Precision-Fed Different Forage To Concentrate Ratios, Noe Alberto Gomez

Animal Science

Understanding the efficiency and digestibility of dietary nutrients in dairy heifers is essential for minimizing costs and environmental impacts of the dairy industry. The objective of this study was to interpret the effects of manipulating rumen-degradable protein (RDP) in a precision feeding system. Eight Holstein ruminally cannulated heifers (14.6 ± 0.1 mo of age, and 386 ± 9.1 kg of weight) were randomly assigned to 2 forage levels: HC (25% forage) and LC (75% forage) and to a degradable protein sequence [0% degradable protein from urea U, 100% casein C (no urea treatment U0); 33% U, 67% C …

Migratory Connectivity And Carry-Over Effects In Northwest Atlantic Loggerhead Turtles (Caretta Caretta, L.), Simona Ceriani

Electronic Theses and Dissertations

Migration is a widespread and complex phenomenon in nature that has fascinated humans for centuries. Connectivity among populations influences their demographics, genetic structure and response to environmental change. Here, I used the loggerhead turtle (Caretta caretta, L.) as a study organism to address questions related to migratory connectivity and carry-over effects using satellite telemetry, stable isotope analysis and GIS interpolation methods. Telemetry identified foraging areas previously overlooked for loggerheads nesting in Florida. Next, I validated and evaluated the efficacy of intrinsic markers as a complementary and low cost tool to assign loggerhead foraging regions in the Northwest Atlantic Ocean (NWA), …