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Full-Text Articles in Physical Sciences and Mathematics

Effects Of Control Release Fertilizers On Nutrient Leaching, Palm Growth And Production Cost, Pushpa Soti, Angie Fleurissaint, Stewart Reed, Krish Jayachandran Nov 2015

Effects Of Control Release Fertilizers On Nutrient Leaching, Palm Growth And Production Cost, Pushpa Soti, Angie Fleurissaint, Stewart Reed, Krish Jayachandran

Department of Earth and Environment

Objective of this study was to evaluate the effect of different controlled release fertilizer technologies on nutrient leaching and plant growth parameters of two palm species, Chinese Fan (Livistona chinensis) and Queen (Syagrus romanzoffiana). We compared Nutri-Pak (12-4-12 controlled release packet) and Harrell’s (12-4-12 controlled release polymer coated urea) against Atlantic (8-4-12 controlled release polymer coated urea, coated sulfate of potash), the most commonly used palm fertilizer in South Florida. Plants were grown in 25 cm (11 L) pots under 70% shade, watered weekly, with pest and weed control done as required. Plant growth parameters: number of leaves, leaf length …


Gaseous Carbon Emissions (Methane And Carbon Dioxide) From Wetland Soils In A Re-Created Everglades Landscape, Bradley R. Schonhoff Nov 2015

Gaseous Carbon Emissions (Methane And Carbon Dioxide) From Wetland Soils In A Re-Created Everglades Landscape, Bradley R. Schonhoff

FIU Electronic Theses and Dissertations

Reducing the rates of greenhouse gas (GHG) emissions is critical in combatting global climate change. Carbon dioxide (CO2) and methane (CH4) are the two most important carbon-based GHGs, for their atmospheric warming potential. Wetlands such as the Florida Everglades play major roles in the global carbon cycle, as varying hydrologic conditions lead to differential production rates of these two GHGs. This study measured CO2 and CH4 emissions in a re-created Everglades ridge-and-slough wetland, where water levels were controlled to reflect natural flood patterns. As expected, lower elevations were flooded longer and produced more CH …


The Effect Of Disturbance And Freshwater Availability On Lower Florida Keys’ Coastal Forest Dynamics, Danielle E. Ogurcak Nov 2015

The Effect Of Disturbance And Freshwater Availability On Lower Florida Keys’ Coastal Forest Dynamics, Danielle E. Ogurcak

FIU Electronic Theses and Dissertations

Coastal forest retreat in the Florida Keys during the 20th century has been attributed to a combination of sea level rise and hurricane storm surge impacts, but the interactions between these two disturbances leading to forest decline are not well understood. The goal of my research was to assess their effects over a period spanning more than two decades, and to examine the relationships between these press and pulse disturbances and freshwater availability in pine rockland, hardwood hammock, and supratidal scrub communities. Impacts and recovery from two storm surges, Hurricanes Georges (1998) and Wilma (2005), were assessed with satellite-derived …


Performance Of High Resolution Satellite Rainfall Products Over Data Scarce Parts Of Eastern Ethiopia, Shimelis B. Gebere, Tena Alamirew, Broder J. Merkel, Assefa M. Melesse Sep 2015

Performance Of High Resolution Satellite Rainfall Products Over Data Scarce Parts Of Eastern Ethiopia, Shimelis B. Gebere, Tena Alamirew, Broder J. Merkel, Assefa M. Melesse

Department of Earth and Environment

Accurate estimation of rainfall in mountainous areas is necessary for various water resource-related applications. Though rain gauges accurately measure rainfall, they are rarely found in mountainous regions and satellite rainfall data can be used as an alternative source over these regions. This study evaluated the performance of three high-resolution satellite rainfall products, the Tropical Rainfall Measuring Mission (TRMM 3B42), the Global Satellite Mapping of Precipitation (GSMaP_MVK+), and the Precipitation Estimation from Remotely-Sensed Information using Artificial Neural Networks (PERSIANN) at daily, monthly, and seasonal time scales against rain gauge records over data-scarce parts of Eastern Ethiopia. TRMM 3B42 rain products show …


Modeling A Phosphorus Credit Trading Program In The Lake Okeechobee Watershed, Juliana Corrales Sep 2015

Modeling A Phosphorus Credit Trading Program In The Lake Okeechobee Watershed, Juliana Corrales

FIU Electronic Theses and Dissertations

Lake Okeechobee is the largest lake in the southeastern United States and is a central component of the hydrology and environment of the Everglades ecosystem in South Florida. The natural state of the lake has been degraded as wetlands and natural habitats in the Lake Okeechobee watershed have been replaced with farms, urban areas, and dairy operations. Excessive phosphorus loadings from these diverse sources have been identified as the leading causes of the lake’s impairment. For more than four decades, many resources have been allocated to regional and local restoration efforts to reduce phosphorus loadings into the lake. However, phosphorus …


Effect Of Yangtze River On Population Genetic Structure Of The Relict Plant Parrotia Subaequalis In Eastern Chin, Qifang Geng, Zhingang Yao, Jie Yang, Jia He, Danbi Wong, Zhongsheng Wang, H. Liu Aug 2015

Effect Of Yangtze River On Population Genetic Structure Of The Relict Plant Parrotia Subaequalis In Eastern Chin, Qifang Geng, Zhingang Yao, Jie Yang, Jia He, Danbi Wong, Zhongsheng Wang, H. Liu

Department of Earth and Environment

Parrotia subaequalis (Hamamelidaceae) is a Tertiary relic species endemic in eastern China. We used inter-simple sequence repeat (ISSR) markers to access genetic diversity and population genetic structure in natural five populations of P. subaequalis. The levels of genetic diversity were higher at species level (H = 0.2031) but lower at population level (H = 0.1096). The higher genetic diversity at species levels might be attributed to the accumulation of distinctive genotypes which adapted to the different habitats after Quaternary glaciations. Meanwhile, founder effects on the early stage, and subsequent bottleneck of population regeneration due to its biological characteristics, environmental features, …


Investigation Of The Lead Isotope Signatures Of Marine Sediments In Relation To The Lead Isotope Signatures Of Northern Andean Ores, Kimberly D. Beck Jul 2015

Investigation Of The Lead Isotope Signatures Of Marine Sediments In Relation To The Lead Isotope Signatures Of Northern Andean Ores, Kimberly D. Beck

FIU Electronic Theses and Dissertations

Lead isotope ratios of ores and igneous rocks in the Central and Southern Andes show a large-scale geographic pattern related to magmatic source processes. This pattern changes in the Northern Andes for reasons that are not well understood; this study is an investigation of potential causes of this change. Deep ocean sediment samples from the Nazca Plate were analyzed for 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb, and the data were compared with published data on central Andean ores and ores and igneous rocks from Ecuador. Lead isotopic compositions of the Nazca Plate sediments …


Improving Satellite-Based Chlorophyll-A Estimating Algorithms In Shallow, Coastal Waters, Tara Blakey Jul 2015

Improving Satellite-Based Chlorophyll-A Estimating Algorithms In Shallow, Coastal Waters, Tara Blakey

FIU Electronic Theses and Dissertations

This work evaluated the improvement to the accuracy of chlorophyll-a (chl-a) estimating algorithms derived from Sea-Viewing Wide Field-of-View Sensor (SeaWIFS) archives of an optically-shallow, subtropical bay. Preliminary investigation into the in situ chl-a measurements showed that the fine spatial and temporal resolution currently only available through satellite remote sensing are required to adequately understand the dynamics of coastal chl-a. The in situ datasets, however, were found to be useful for developing chl-a algorithms by allowing for 1) identification of appropriate times of year for classifying benthic habitats and 2) the assumption of annually …


Land Use /Land Cover Driven Surface Energy Balance And Convective Rainfall Change In South Florida, Hari P. Kandel Jul 2015

Land Use /Land Cover Driven Surface Energy Balance And Convective Rainfall Change In South Florida, Hari P. Kandel

FIU Electronic Theses and Dissertations

Modification of land use/land cover in South Florida has posed a major challenge in the region’s eco-hydrology by shifting the surface-atmosphere water and energy balance. Although drainage and development in South Florida took place extensively between the mid- and late- 20th century, converting half of the original Everglades into agricultural and urban areas, urban expansion still accounts for a dominant mode of surface cover change in South Florida. Changes in surface cover directly affect the radiative, thermophysical and aerodynamic parameters which determine the absorption and partitioning of radiation into different components at the Earth surface. The alteration is responsible …


Hydrologic Controls Of Coastal Groundwater Discharge In Southern Taylor Slough, Everglades National Park, Florida, Edward Linden Jul 2015

Hydrologic Controls Of Coastal Groundwater Discharge In Southern Taylor Slough, Everglades National Park, Florida, Edward Linden

FIU Electronic Theses and Dissertations

This project empirically determined the controls of groundwater discharge potential and surface water chemistry in southern Taylor Slough, Everglades National Park, Florida. Potential for groundwater discharge was calculated as the difference in equivalent freshwater stage between groundwater and surface water on a daily basis for two sites (upland and coastal) along southern Taylor Slough. Upstream water stages were shown to vary most similarly to the timing of groundwater discharge potential in coastal Taylor Slough. Surface water major ion chemistry did not apparently change as a result of groundwater discharge potential. Surface water major ion chemistry at the coastal site was …


Flow Regime Classification And Hydrological Characterization: A Case Study Of Ethiopian Rivers, Belete Berhanu, Yilma Seleshi, Solomon S. Demisse, Assefa M. Melesse Jun 2015

Flow Regime Classification And Hydrological Characterization: A Case Study Of Ethiopian Rivers, Belete Berhanu, Yilma Seleshi, Solomon S. Demisse, Assefa M. Melesse

Department of Earth and Environment

The spatiotemporal variability of a stream flow due to the complex interaction of catchment attributes and rainfall induce complexity in hydrology. Researchers have been trying to address this complexity with a number of approaches; river flow regime is one of them. The flow regime can be quantified by means of hydrological indices characterizing five components: magnitude, frequency, duration, timing, and rate of change of flow. Similarly, this study aimed to understand the flow variability of Ethiopian Rivers using the observed daily flow data from 208 gauging stations in the country. With this process, the Hierarchical Ward Clustering method was implemented …


Black Carbon: Sources, Mobility And Fate In Freshwater Systems, Sasha Wagner Jun 2015

Black Carbon: Sources, Mobility And Fate In Freshwater Systems, Sasha Wagner

FIU Electronic Theses and Dissertations

Black carbon (BC) is a complex mixture of polycondensed aromatic compounds produced by the incomplete combustion of biomass during events such as wildfires and the burning of fossil fuels. Black carbon was initially considered to be a refractory form of organic matter. However, recent studies have shown that BC can be quite mobile and reactive in the terrestrial environment. Black carbon can be translocated from soils and sediments in the form of dissolved BC (DBC). A global correlation between DBC and bulk dissolved organic carbon (DOC) has been established for fluvial systems where DBC comprises approximately 10% of the total …


Supervised Classification Of Benthic Reflectance In Shallow Subtropical Waters Using A Generalized Pixel-Based Classifier Across A Time Series, Tara Blakey, Assefa M. Melesse, Margaret O. Hall Apr 2015

Supervised Classification Of Benthic Reflectance In Shallow Subtropical Waters Using A Generalized Pixel-Based Classifier Across A Time Series, Tara Blakey, Assefa M. Melesse, Margaret O. Hall

Department of Earth and Environment

We tested a supervised classification approach with Landsat 5 Thematic Mapper (TM) data for time-series mapping of seagrass in a subtropical lagoon. Seagrass meadows are an integral link between marine and inland ecosystems and are at risk from upstream processes such as runoff and erosion. Despite the prevalence of image-specific approaches, the classification accuracies we achieved show that pixel-based spectral classes may be generalized and applied to a time series of images that were not included in the classifier training. We employed in-situ data on seagrass abundance from 2007 to 2011 to train and validate a classification model. We created …


Changing Bacterial Growth Efficiencies Across A Natural Nutrient Gradient In An Oligotrophic Estuary, Amber A. Kiger Mar 2015

Changing Bacterial Growth Efficiencies Across A Natural Nutrient Gradient In An Oligotrophic Estuary, Amber A. Kiger

FIU Electronic Theses and Dissertations

Recent studies have characterized coastal estuarine systems as important components of the global carbon cycle. This study investigated carbon cycling through the microbial loop of Florida Bay by use of bacterial growth efficiency calculations. Bacterial production, bacterial respiration, and other environmental parameters were measured at three sites located along a historic phosphorus-limitation gradient in Florida Bay and compared to a relatively nutrient enriched site in Biscayne Bay. A new method for measuring bacterial respiration in oligotrophic waters involving tracing respiration of 13C-glucose was developed. The results of the study indicate that 13C tracer assays may provide a better …


Development And Characterization Of Polymorphic Microsatellite Markers (Ssrs) For An Endemic Plant, Pseudolarix Amabilis (Nelson) Rehd. (Pinaceae), Qi-Fang Geng, Jun Liu, Lin Sun, Hong Liu, Yan Ou-Yang, Ying Cai, Xin-Sheng Tang, Hong-Wei Zhang, Zhing-Sheng Wang, Shu-Qing An Feb 2015

Development And Characterization Of Polymorphic Microsatellite Markers (Ssrs) For An Endemic Plant, Pseudolarix Amabilis (Nelson) Rehd. (Pinaceae), Qi-Fang Geng, Jun Liu, Lin Sun, Hong Liu, Yan Ou-Yang, Ying Cai, Xin-Sheng Tang, Hong-Wei Zhang, Zhing-Sheng Wang, Shu-Qing An

Department of Earth and Environment

Pseudolarix (Pinaceae) is a vulnerable (sensu IUCN) monotypic genus restricted to southeastern China. To better understand levels of genetic diversity, population structure and gene flow among populations of P. amabilis, we developed five compound SSR markers and ten novel polymorphic expressed sequence tags (EST) derived microsatellites. The results showed that all 15 loci were polymorphic with the number of alleles per locus ranging from two to seven. The expected and observed heterozygosities varied from 0.169 to 0.752, and 0.000 to 1.000, respectively. The inbreeding coefficient ranged from −0.833 to 1.000. These markers will contribute to research on genetic diversity and …


Changes Of Soil Biogeochemistry Under Native And Exotic Plants Species, Yujie Hua Jan 2015

Changes Of Soil Biogeochemistry Under Native And Exotic Plants Species, Yujie Hua

FIU Electronic Theses and Dissertations

Invasive plant species are major threats to the biodiversity and ecosystem stability. The purpose of this study is to understand the impacts of invasive plants on soil nutrient cycling and ecological functions. Soil samples were collected from rhizosphere and non-rhizosphere of both native and exotic plants from three genera, Lantana, Ficus and Schinus, at Tree Tops Park in South Florida, USA. Experimental results showed that the cultivable bacterial population in the soil under Brazilian pepper (invasive Schinus) was approximately ten times greater than all other plants. Also, Brazilian pepper lived under conditions of significantly lower available phosphorus …


Sensors Best Paper Award 2015, Vittorio M.N. Passaro, W. Rudolf Seitz, Assefa M. Melesse, Alexander Star, Leonhard Reindl Jan 2015

Sensors Best Paper Award 2015, Vittorio M.N. Passaro, W. Rudolf Seitz, Assefa M. Melesse, Alexander Star, Leonhard Reindl

Department of Earth and Environment

Since 2011, an annual award system was instituted to recognize outstanding Sensors papers that are related to sensing technologies and applications and meet the aims, scope and high standards of this journal [1–4]. This year, the winners were chosen by the Section Editor-in-Chiefs of Sensors from among all the papers published in 2011 to track citations. Reviews and full research articles were considered separately. We gladly announce that the following eight papers were awarded the Sensors Best Paper Award in 2015.