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Full-Text Articles in Physical Sciences and Mathematics

Population Ecology Of A Caribbean Epiphyte Trichocentrum Undulatum (Orchidaceae): Defining Habitat And The Effects Of Herbivory And Hurricanes At Its Peripheral And Core Range, Haydee Borrero Jan 2022

Population Ecology Of A Caribbean Epiphyte Trichocentrum Undulatum (Orchidaceae): Defining Habitat And The Effects Of Herbivory And Hurricanes At Its Peripheral And Core Range, Haydee Borrero

FIU Electronic Theses and Dissertations

Population ecology studies are central to species conservation. My dissertation focused on the Florida state-listed endangered orchid, Trichocentrum undulatum at its northern-most range in the Everglades National Park (ENP), Florida and multiple populations throughout its core range in Cuba. Through surveying populations of T. undulatum across this range from 2013-2021, I made a new reporting on the occurrence of a specialized insect herbivore, Melanagromyza miamensis in Cuba (Chapter 1). This flower-crippling herbivore was previously known only in the ENP. With this discovery I assess the intensity and impacts of this herbivore, as well as others on T. undulatum across the …


In-Vitro Micropropagation And Acclimatization Of Selected Florida Native Orchids, Andrew Mullin Nov 2021

In-Vitro Micropropagation And Acclimatization Of Selected Florida Native Orchids, Andrew Mullin

FIU Electronic Theses and Dissertations

Florida is home to 106 native orchid species with the majority of them being endangered or critically imperiled, according to the International Union for Conservation of Nature (IUCN) and the Institute for Regional Conservation (IRC). In nature orchid germination rates are very low because they lack an endosperm, instead depending on an obligate relationship with a mycorrhizal fungus for nutrients. Most orchid seeds can be germinated in-vitro without the need for specific mycorrhizal fungi and therefore high rates of germination can be achieved. This study aims are a) to establish the fastest and most efficient in-vitro seed germination media and …


Comparison Of Modern And Mid-Holocene Benthic Foraminifera To Assess Recent Environmental Change In Almirante Bay, Caribbean Panama, Maria N. Gudnitz Mar 2021

Comparison Of Modern And Mid-Holocene Benthic Foraminifera To Assess Recent Environmental Change In Almirante Bay, Caribbean Panama, Maria N. Gudnitz

FIU Electronic Theses and Dissertations

This study used the diversity and distribution of benthic foraminiferal assemblages of Almirante Bay, Caribbean Panama, as environmental proxies to compare modern coral, seagrass and mangrove habitats to mid-Holocene coral reef facies on the island of Isla Colón, to investigate both natural and human-influenced changes.

The modern study associated species and assemblage characteristics with environmental conditions related to degraded water quality. Assemblages were fairly similar among neighboring habitats but differed in species proportions, while several stress-tolerant taxa might indicate eutrophic conditions. Diversity appeared to be regionally controlled by freshwater input irrespective of habitat type, was generally lower near the mainland …


Connections In The Underworld: A Morphological And Molecular Study Of Diversity And Connectivity Among Anchialine Shrimp., Robert Eugene Ditter Nov 2020

Connections In The Underworld: A Morphological And Molecular Study Of Diversity And Connectivity Among Anchialine Shrimp., Robert Eugene Ditter

FIU Electronic Theses and Dissertations

This research investigates the distribution and population structure of crustaceans, endemic to anchialine systems in the tropical western Atlantic focusing on cave-dwelling shrimp from the family Barbouriidae. Taxonomic and molecular tools (genetic and genomic) are utilized to examine population dynamics and the presence of phenotypic hypervariation (PhyV) of the critically endangered species Barbouria cubensis (von Martens, 1872). The presence of PhyV and its geographic distribution is investigated among anchialine populations of B. cubensis from 34 sites on Abaco, Eleuthera, and San Salvador, Bahamas. Examination of 54 informative morphological characters revealed PhyV present in nearly 90% (n=463) of specimens with no …


Hydrogeophysical Characterization And Imaging In The Mangrove Lakes Region Of Everglades National Park And Big Pine Key, Florida, Usa, Michael Eyob Kiflai Jul 2020

Hydrogeophysical Characterization And Imaging In The Mangrove Lakes Region Of Everglades National Park And Big Pine Key, Florida, Usa, Michael Eyob Kiflai

FIU Electronic Theses and Dissertations

Coastal groundwater aquifers are susceptible to saltwater intrusion from natural and anthropogenic sources. Everglades National Park (ENP) has been adversely impacted by past human activities that altered freshwater flow through the system. In Big Pine Key (BPK), the flat and low-lying topography less than 2m makes the freshwater lens vulnerable to tidal and storm surge events. This study investigated different inversion scenarios and used Electrical Resistivity Tomography (ERT) and Electromagnetic (EM) survey to characterize the spatial and temporal change of the groundwater chemistry and image the aquifers. In Big Pine Key, Hurricane Irma made landfall as a category 4 storm …


An Economic Assessment Of The Impacts Of Outdoor Water Use Restrictions In South Florida, Lara Kiesau May 2020

An Economic Assessment Of The Impacts Of Outdoor Water Use Restrictions In South Florida, Lara Kiesau

FIU Electronic Theses and Dissertations

Population growth and climate change are important factors determining residential water demand. Most residential water consumption can be attributed to outdoor use. To reduce water consumption, outdoor water use restrictions (OWRs) have become a popular policy tool in the last decades. We developed an integrated framework consisting of a Difference in Differences (DID) analysis, Value Function approach and Discrete Choice Model to perform an economic assessment of the impacts of OWRs in South Florida. The results reveal a decreasing effect of up to 133 gallons per person per month due to the strictest OWR, equaling a yearly value of almost …


Modeling Drought, Drought Teleconnection, And Its Effect On Groundwater Level Dynamics In The Biscayne Aquifer, Anteneh Z. Abiy Apr 2020

Modeling Drought, Drought Teleconnection, And Its Effect On Groundwater Level Dynamics In The Biscayne Aquifer, Anteneh Z. Abiy

FIU Electronic Theses and Dissertations

Developing a self-sufficient water supply system in Southeast Florida is one input to the success of the ongoing restoration effort in the Everglades. Maintaining a high groundwater level in the urban side of the Biscayne Aquifer (BA) is important to sustain the urban water supply. However, the long-term groundwater table condition in the Biscayne Aquifer (BA) is threatened by a combination of drought, groundwater pumping, and sea-level rise. Further, the long-term drought pattern, drought drivers, and the aquifer’s response to drought and other stress conditions are not well known. As a result, options that would help to maintain a high …


Generating Alternatives: The Possible Energy Transitions For France And Germany After The Paris Accord, Anna Fache Jun 2019

Generating Alternatives: The Possible Energy Transitions For France And Germany After The Paris Accord, Anna Fache

FIU Electronic Theses and Dissertations

Following the Paris Accord of 2015, multiple countries, including France and Germany, promised to reduce their greenhouse gas emissions in order to slow down climate change. Current energy production and consumption patterns do not allow for such targets. Meeting these emission reduction goals requires a transition in energy production. Energy transitions can be inefficient and costly if not planned properly, and multiple constraints need to be taken into account when putting such a process in place. The model proposed in the present study aims to find the most cost-effective energy portfolios for France and Germany, two highly industrialized nations in …


Cultural Politics Of Community-Based Conservation In The Buffer Zone Of Chitwan National Park, Nepal, Yogesh Dongol Jun 2018

Cultural Politics Of Community-Based Conservation In The Buffer Zone Of Chitwan National Park, Nepal, Yogesh Dongol

FIU Electronic Theses and Dissertations

The dissertation research examines the socio-economic and political effects of community-based conservation initiatives within the Bagmara buffer zone community forests of Chitwan National Park, Nepal. In particular, the study investigates the role of buffer zones creation in structuring the way rural property rights have been defined, negotiated, and contested, in reinforcing or reducing patterns of ethnic dominance and exclusion, and in influencing how cultural identities are constituted and renegotiated. Using a political ecology framework with a specific focus on theoretical concepts of environmentality and territorialization, I conducted 12 months ethnographic and quantitative survey field research in the buffer zone communities …


Community-Governed Multifunctional Landscapes And Forest Conservation In The Sierra Norte Of Oaxaca, Mexico, Barbara Pazos Almada Jul 2016

Community-Governed Multifunctional Landscapes And Forest Conservation In The Sierra Norte Of Oaxaca, Mexico, Barbara Pazos Almada

FIU Electronic Theses and Dissertations

Community forestry is an evolving approach to forest management, shown to maintain forest cover, while generating income for local communities. In Sierra Norte (SN), a region with no public protected areas, indigenous communities have been actively conserving their forests for decades, through conservation zoning and careful management of their logging areas. This study found that across 22 communities in SN, an estimated 2,949,116.50 m3 of timber were produced from 1993 to 2013, while the region maintains 78% forest cover. About 75% of the forest is under some form of community conservation. Community governance plays a major role, as rules …


Trees In The Agricultural Matrix: Reforestation Processes In A Tropical Dry Landscape In Chinandega, Nicaragua, Brittany A. Duffy Jul 2016

Trees In The Agricultural Matrix: Reforestation Processes In A Tropical Dry Landscape In Chinandega, Nicaragua, Brittany A. Duffy

FIU Electronic Theses and Dissertations

Tree management practices in the tropical dry forest region of Nicaragua were examined to determine opportunities and factors influencing tree-planting initiatives and forest recovery within the agricultural matrix. A 217.11 ha tree inventory and 44 social surveys were conducted in three rural communities. The inventory found 88 species, 66.68% were native, and 70 valued for multiple uses. Farmers’ reasons for maintaining trees varied, emphasizing live fencing, wood, and fruit. The landscape also contains a tree plantation and a riparian forest, and the origins and management of these tree cover components of the landscape are also considered. Tree planting interventions should …


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 …


A Spatial And Temporal Analysis Of Land Use And Water Quality In Southern Miami Dade County, Mario Londono Jun 2015

A Spatial And Temporal Analysis Of Land Use And Water Quality In Southern Miami Dade County, Mario Londono

FIU Electronic Theses and Dissertations

This thesis research employs a multi-pronged analysis approach to contribute to the existing knowledge regarding land use and water quality in southern Miami Dade County. Nutrient concentrations for TP, NOx-N, and NH3-N were evaluated for water quality monitoring stations across seven canals for two time periods: 1990-2003 and 2009-2014. Overall, the sites did not surpass the mandated TP threshold but a number of sites exceeded the NOx-N and NH3-N criteria set by multiple government agencies. Statistical tests demonstrated that the sites had differing distributions, not sharing similar median concentrations. Land use classifications were derived for the area interest for the …


Sustainability Analysis Of Domestic Rainwater Harvesting Systems For Current And Future Water Security In Rural Mexico, Elena E. Neibaur Jun 2015

Sustainability Analysis Of Domestic Rainwater Harvesting Systems For Current And Future Water Security In Rural Mexico, Elena E. Neibaur

FIU Electronic Theses and Dissertations

Rainwater harvesting, the act of capturing and storing rain, is an ancient practice that is increasingly utilized today by communities to address water supply needs. This thesis examines whether domestic rainwater harvesting systems (DRWHS) can be a sustainable solution as defined by social, water quality, and technical feasibility for water security in semi-arid, rural environments. For this study, 50 surveys and 17 stored rainwater analyses were conducted in San Jose Xacxamayo, Mexico, in conjunction with my Peace Corps work of implementing 82 DRWHS. Results showed that all DRWHS were socially feasible because of cultural acceptance and local capacity. Water quality …


Habitat Use Of The Key Largo Woodrat (Neotoma Floridana Smalli), Lauren J. Barth Nov 2014

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 …


Characterization Of Rhizobial Diversity And Relationship Of Rhizobial Partner And Legume Performance In Four South Florida Pine Rockland Soils, Vanessa Sánchez Mar 2014

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 …


Recreational Angler Perspectives Of Nonnative Fish Species And Mercury Advisories, Christopher J. Edwards Nov 2013

Recreational Angler Perspectives Of Nonnative Fish Species And Mercury Advisories, Christopher J. Edwards

FIU Electronic Theses and Dissertations

The central Everglades serve as a Wildlife Management Area and as a Water Conservation Area for the Miami-Fort Lauderdale metropolitan area. It is also home to over 22 nonnative freshwater fish species and carries restrictive fish consumption guidelines for Mercury. In my study, boat anglers and canal bank anglers were personally interviewed in the field, to research their awareness and perspectives of these potential environmental and health threats. The study found 78% of anglers were aware of the presence of nonnative fish species, but favored native fish species, and that 69% were aware of mercury advisories, but did not eat …


An Economic Valuation Analysis Of Buccoo Reef Marine Park, Tobago, West Indies, Dionne J. Da Costa Nov 2010

An Economic Valuation Analysis Of Buccoo Reef Marine Park, Tobago, West Indies, Dionne J. Da Costa

FIU Electronic Theses and Dissertations

The purpose of this study was to evaluate tourism capacity, the effectiveness of the management plan and the visitors’ willingness to pay (WTP) for increased conservation effort in the Buccoo Reef Marine Park (BRMP) in Tobago. Non-market contingent valuation was applied to estimate tourists’ WTP, using the data from a survey of 164 tourists. Local residents and government agencies were consulted to evaluate the management plan and the tourism capacity. Eighty-eight percent of local residents stated that the park was not well managed and that they lacked trust in the park agency. The density of tourists was 67-97% more than …