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University of Florida
1.
Brooks, Mollie E.
Four Permutations of Growth, Reproduction, and Survival.
Degree: PhD, Zoology - Biology, 2012, University of Florida
URL: https://ufdc.ufl.edu/UFE0044620
► This dissertation contains four studies in quantitative ecology. The first study deals with the optimal life history strategy of flowering perennial plants. Previous work has…
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▼ This dissertation contains four studies in quantitative ecology. The first study deals with the optimal life history strategy of flowering perennial plants. Previous work has shown that it is optimal for plants to be non-reproductive when small, produce male flowers at a medium size, and produce female flowers when large, with the assumption that reproductive rate increases with size. However, reproductive rate does not always increase with size. The study presented here shows that size-dependent mortality can select for sex-change in the same way as size-dependent reproduction. The second study develops a statistical method for detecting differences in growth rate among individuals. Detecting individual variation in growth is important because (1) it could indicate a life history tradeoff and (2) fast growers contribute disproportionately to population growth rates. Detecting among individual differences in growth rates is straightforward when individuals are marked and measured repeatedly. However, marking individuals is not always ethical or feasible. We used maximum likelihood estimation to fit a statistical model to simulated data to test our method. For a given sample size, more information can be gained by marking individuals, but our method increases the range of experimental designs for detecting among individual variation in growth rates. The third and fourth studies deal with demographic data collected from Heliconia accuminata, a perennial plant that grows in the Amazon understory. The Amazon is being fragmented by development by humans cutting roads and farms into the forest. The plants’ rates of growth, survival, and reproductive effort were modeled using generalized linear mixed models; uncertainty was estimated using Markov chain Monte Carlo sampling. The study indicates that, certain environmental conditions increase mortality and reproduction. Fragmentation may also be reducing temporal heterogeneity in vital rates. Individual based models were used to predict how heterogeneity affects the population growth rate. All forms of heterogeneity increased the growth rates of our simulated populations. ( en )
Advisors/Committee Members: Bolker, Benjamin M (committee chair), St. Mary, Colette M (committee member), Holt, Robert D (committee member), Bruna, Emilio M (committee member).
Subjects/Keywords: Demography; Ecology; Forests; Inflorescences; Modeling; Mortality; Plants; Population growth rate; Population size; Statistical discrepancies; admb – change – demography – generalized – history – life – linear – mixed – models – sex – stochastic
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APA (6th Edition):
Brooks, M. E. (2012). Four Permutations of Growth, Reproduction, and Survival. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0044620
Chicago Manual of Style (16th Edition):
Brooks, Mollie E. “Four Permutations of Growth, Reproduction, and Survival.” 2012. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0044620.
MLA Handbook (7th Edition):
Brooks, Mollie E. “Four Permutations of Growth, Reproduction, and Survival.” 2012. Web. 16 Jan 2021.
Vancouver:
Brooks ME. Four Permutations of Growth, Reproduction, and Survival. [Internet] [Doctoral dissertation]. University of Florida; 2012. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0044620.
Council of Science Editors:
Brooks ME. Four Permutations of Growth, Reproduction, and Survival. [Doctoral Dissertation]. University of Florida; 2012. Available from: https://ufdc.ufl.edu/UFE0044620

University of Florida
2.
Bhotika, Smriti.
Spatial Ecology of Large Herbivores in the Serengeti Ecosystem.
Degree: PhD, Interdisciplinary Ecology, 2012, University of Florida
URL: https://ufdc.ufl.edu/UFE0045013
► With rapidly increasing human populations, ensuring thelong-term effectiveness of protected areas through wise management isincreasingly important. To conservebiodiversity, species abundance and distribution patterns must be…
(more)
▼ With rapidly increasing human populations, ensuring thelong-term effectiveness of protected areas through wise management isincreasingly important. To conservebiodiversity, species abundance and distribution patterns must be identifiedand underlying processes must be understood. This research examined how human activities, spatial processes, andspecies traits collectively influence the abundance, occupancy, andinterspecific associations of species in the Serengeti ecosystem in EastAfrica. Thirteen large herbivore specieswere investigated using nine annual aerial surveys from 1988-2006. Using spatial regression models, influencesof habitat characteristics on community distributions were assessed. Results indicate efforts to manage forspecies richness would involve emphasizing habitat characteristics differentfrom those that would maximize total abundance, biomass, or metabolicrate. Human activities could be managedto mitigate negative effects on wildlife habitat use (e.g., monitor roadusage). It may also be important tomaintain the spatial and temporal heterogeneity of plant resources due to theirinfluence on the spatial distribution of the community. Occupancy and average abundance of individualspecies differed. Species with lowoccupancy and abundance tend to have distinct social behavior and specifichabitat associations, whereas species with high occupancy and abundance tend tobe migratory and smaller. Species withstrong grouping behavior tend to deviate from these general patterns. Rank occupancy-abundance profiles revealed thatthe overall shape of the distribution (straight, S-shaped, etc.) for mostspecies appears to be fairly consistent over time. Clustering of species decreased in relationto body mass, with migratory species showing more variability inaggregation. The structure of thecommunity, summarized using rank-abundance plots, indicated a few speciesnumerically dominate and overall community structure appears constant overtime. Observed strong negativeassociations tend to be for species with large body sizes and which form largegroups, suggesting competition for resources and space. In addition, negative interactions may berelated to habitat specificity. Weaknegative associations are observed for migratory species. The patterns observed provide an expansiveview of the large herbivore community for this study area and could potentiallybe applied to other systems or species and to predict effects of environmentalchanges and management strategies on communities. ( en )
Advisors/Committee Members: Holt, Robert D (committee chair), Binford, Michael W (committee member), Christman, Mary C (committee member), Palmer, Todd (committee member), Bolker, Benjamin M (committee member).
Subjects/Keywords: Biomass; Coordinate systems; Dry seasons; Ecology; Herbivores; Rainy seasons; Ruminants; Spatial models; Species; Wildebeest; abundance – community – distribution – diversity
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APA (6th Edition):
Bhotika, S. (2012). Spatial Ecology of Large Herbivores in the Serengeti Ecosystem. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0045013
Chicago Manual of Style (16th Edition):
Bhotika, Smriti. “Spatial Ecology of Large Herbivores in the Serengeti Ecosystem.” 2012. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0045013.
MLA Handbook (7th Edition):
Bhotika, Smriti. “Spatial Ecology of Large Herbivores in the Serengeti Ecosystem.” 2012. Web. 16 Jan 2021.
Vancouver:
Bhotika S. Spatial Ecology of Large Herbivores in the Serengeti Ecosystem. [Internet] [Doctoral dissertation]. University of Florida; 2012. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0045013.
Council of Science Editors:
Bhotika S. Spatial Ecology of Large Herbivores in the Serengeti Ecosystem. [Doctoral Dissertation]. University of Florida; 2012. Available from: https://ufdc.ufl.edu/UFE0045013

University of Florida
3.
Stier, Adrian Craig.
Predation and Habitat Drive Reef Fish Community Organization.
Degree: PhD, Zoology - Biology, 2012, University of Florida
URL: https://ufdc.ufl.edu/UFE0043978
► I examined the ecological drivers of coral reef fish abundance and diversity in the South Pacific. The availability, spatial arrangement, and fragmentation of coral habitat…
(more)
▼ I examined the ecological drivers of coral reef fish abundance and diversity in the South Pacific. The availability, spatial arrangement, and fragmentation of coral habitat is heterogeneous at local and global scales. The first goal of my research was to document how fish communities vary in abundance, diversity, and composition. The second goal was to quantify how input of larvae shifts across heterogeneous landscapes. The third goal was to describe how competition and predation reshape patterns of abundance and diversity initially established at colonization. A suite of surveys in Moorea, French Polynesia documented substantial spatio-temporal variation in the abundance and diversity of fishes. Using two experiments where I manipulated habitat availability, spatial arrangement, and fragmentation I showed that the supply of larvae can vary substantially across patches of variable configuration. Using a combination of modeling and experiments I showed that patterns initially established at settlement can be substantially modified by competition and predation post-settlement. In subsequent experiments I isolated the effects of predators from habitat configuration. I found that, for a focal predator, the density of predators does not affect each predator's foraging behavior but that the presence of a competitor can substantially augment the rate at which predators consume prey. I also showed that at the community level, the effect of predators on prey abundance, diversity, and species composition is a function of both predator density and predator timing of arrival. Lastly, I explored patterns of predator and prey biodiversity at large spatial scales spanning 55 islands in the South Pacific. Specifically, I showed that prey are much more sensitive to shifts in island size and isolation relative to predators, suggesting trophic level dependency of species to biogeographic characteristics. Collectively my findings show that reef fish communities are exceptionally variable at multiple spatial scales, and that this variation is a driven by a suite of ecological processes including dispersal, competition, and predation. The research offers general insight into the interface between landscape ecology and trophic interactions. ( en )
Advisors/Committee Members: Osenberg, Craig W (committee chair), Holt, Robert D (committee member), St. Mary, Colette M (committee member), Palmer, Todd (committee member), Bolker, Benjamin M (committee member), Fletcher Jr., Robert Jeffrey (committee member).
Subjects/Keywords: Coral reefs; Corals; Ecology; Fish; Food webs; Functional responses; Mortality; Predation; Predators; Species; biogeography – coral – fish – predation – reef
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APA ·
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APA (6th Edition):
Stier, A. C. (2012). Predation and Habitat Drive Reef Fish Community Organization. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0043978
Chicago Manual of Style (16th Edition):
Stier, Adrian Craig. “Predation and Habitat Drive Reef Fish Community Organization.” 2012. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0043978.
MLA Handbook (7th Edition):
Stier, Adrian Craig. “Predation and Habitat Drive Reef Fish Community Organization.” 2012. Web. 16 Jan 2021.
Vancouver:
Stier AC. Predation and Habitat Drive Reef Fish Community Organization. [Internet] [Doctoral dissertation]. University of Florida; 2012. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0043978.
Council of Science Editors:
Stier AC. Predation and Habitat Drive Reef Fish Community Organization. [Doctoral Dissertation]. University of Florida; 2012. Available from: https://ufdc.ufl.edu/UFE0043978

University of Florida
4.
Blohm, Gabriela.
Abiotic Stress, Grazing and Disease Implications of Global Change on Zostera Marina Seagrasses.
Degree: MS, Zoology, 2008, University of Florida
URL: https://ufdc.ufl.edu/UFE0022281
► The effects of anthropogenic activities go beyond the non-living components of ecosystems; humans are directly altering biological communities. Understanding the implications of changing abiotic regimes…
(more)
▼ The effects of anthropogenic activities go beyond the non-living components of ecosystems; humans are directly altering biological communities. Understanding the implications of changing abiotic regimes on the strength of biological interactions and rates of primary production is important for predicting the ecological effects of climate change. Seagrass ecosystems are of particular interest, given their high rates of primary productivity and simultaneous exposure to a number of factors associated with climate change. Ecosystems undergo simultaneous changes in their natural environment. Extrapolating the effects of single stressors from controlled laboratory settings to natural settings has often proven insufficient; changes in abiotic regimes often occur simultaneously in the environment. Seagrass ecosystems are ideal for conducting multi-factor studies at the mesocosm scale through replicated experimental manipulation. We investigated the effects of increased temperature, nutrient enrichment and grazing pressure on Zostera marina disease, biomass and senescence in a replicated mesocosm experiment at the Virginia Institute of Marine Science in Gloucester Point, VA. We found that an average daily temperature increase of 1.7 degrees C results in a reduction of biomass and an increase in senescence. Contrary to previous studies, which showed that increased temperature gives rise to an increase in disease-driven necrosis, we found that nutrient enrichment increased the proportion of grass that exhibited necrosis due to disease. We found no grazer effect and no significant interaction effects, although we caution that the statistical power of the experiments was low. Our results suggest that the grazing, increased temperature and nutrient enrichment operate through different pathways, given that they did not show synergies or antagonisms. In the context of climate change and seagrass disease, our results do not support the previous studies that have reported seagrass diebacks that were associated with disease outbreaks due to warmer water temperatures. ( en )
Advisors/Committee Members: Osenberg, Craig W. (committee chair), Mack, Michelle C. (committee member), Bolker, Benjamin M. (committee member).
Subjects/Keywords: Biomass; Climate change; Crustaceans; Ecology; Ecosystems; Fertilizers; Marinas; Necrosis; Nutrients; Water temperature; climate, grazing, labyrinthula, nitrogen, seagrass, zostera
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APA ·
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MLA ·
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CSE |
Export
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APA (6th Edition):
Blohm, G. (2008). Abiotic Stress, Grazing and Disease Implications of Global Change on Zostera Marina Seagrasses. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0022281
Chicago Manual of Style (16th Edition):
Blohm, Gabriela. “Abiotic Stress, Grazing and Disease Implications of Global Change on Zostera Marina Seagrasses.” 2008. Masters Thesis, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0022281.
MLA Handbook (7th Edition):
Blohm, Gabriela. “Abiotic Stress, Grazing and Disease Implications of Global Change on Zostera Marina Seagrasses.” 2008. Web. 16 Jan 2021.
Vancouver:
Blohm G. Abiotic Stress, Grazing and Disease Implications of Global Change on Zostera Marina Seagrasses. [Internet] [Masters thesis]. University of Florida; 2008. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0022281.
Council of Science Editors:
Blohm G. Abiotic Stress, Grazing and Disease Implications of Global Change on Zostera Marina Seagrasses. [Masters Thesis]. University of Florida; 2008. Available from: https://ufdc.ufl.edu/UFE0022281

University of Florida
5.
Hrycyshyn, Gabrielle E.
Survival Probabilities and Density of Four Sympatric Species of Freshwater Turtles in Florida.
Degree: MS, Interdisciplinary Ecology, 2007, University of Florida
URL: https://ufdc.ufl.edu/UFE0021036
► Turtles are important, and often neglected, components of their ecosystems, and many turtle species are endangered. I studied four species of common freshwater turtles over…
(more)
▼ Turtles are important, and often neglected, components of their ecosystems, and many turtle species are endangered. I studied four species of common freshwater turtles over a five year period in Wekiwa Springs State Park (WSSP), Apopka,
Florida. These four turtle species were the Peninsula Cooter (Pseudemys peninsularis),
Florida Red-bellied Cooter (P. nelsoni), Loggerhead Musk Turtle (Sternotherus minor minor) and Stinkpot (S. odoratus). For each species I estimated annual recapture probabilities, population density, biomass, annual survival probabilities and realized population growth rate using capture-mark-recapture data from March 2000 to November 2005. My density estimates showed significant declines throughout the study for both Pseudemys species, and non-significant increases in density for both Sternotherus species. These findings are not directly corroborated by the estimated realized population growth rates, which suggest that P. peninsularis populations are increasing non-significantly, and P. nelsoni populations are declining non-significantly. I postulate that the apparent disagreement between the realized population growth rate and density estimates arises from the need to account for temporal variability in estimates of realized population growth rate. Overall my findings suggest that none of these turtle species are in danger, and the apparent declines in both Pseudemys species appear to stabilize toward the end of the study. There are numerous environmental factors that could impact the future health of the spring ecosystem and these turtle populations. These include invasion by the aquatic plant Hydrilla verticillata, which necessitates management activities that many disturb the turtles, increased nitrate pollution and increased water usage and therefore decreased spring output. I recommend monitoring of these turtle populations to ensure that should population declines occur appropriate management actions can be taken. ( en )
Advisors/Committee Members: Bjorndal, Karen (committee chair), Bolten, Alan B. (committee member), Bolker, Benjamin M. (committee member).
Subjects/Keywords: Biomass; Density estimation; Female animals; Geometric mean; Lagoons; Population estimates; Population growth rate; Sex ratio; Species; Turtles; 2000, 2001, 2002, 2003, 2004, 2005, abundance, aic, akaike, apalone, apopka, apparent, barrier, bellied, belly, biomass, capture, carapace, chelydra, chicken, chrysea, cjs, cmr, common, cooter, cooters, cormack, criterion, decrease, deirochelys, demographic, density, eared, elegans, emigrating, emigration, emmigrating, emmigration, emydid, eutrophication, female, ferox, fertilizer, fit, florida, floridana, fluctuation, freshwater, geometric, goodness, growth, hydrilla, immigrating, immigration, increase, information, invasive, inverse, iteroparous, jolly, kinosternid, lambda, late, loggerhead, male, mark, mass, maturity, mean, migrating, migration, minor, model, musk, nelsoni, nitrate, odoratus, osceola, overdispersion, park, peninsula, peninsularis, plastron, pollution, population, pradel, program, pseudemys, qaic, rainbow, rate, ratio, realized, recapture, red, redbellied, redbelly, regression, release, reticularia, reverse, robust, rock, rsrsp, run, scripta, seber, septic, serpentina, sex, sexual, shell, silt, silting, slider, sliders, snapping, softshell, spring, springs, state, sternotherus, stinkpot, survival, survive, sympatric, tank, temporal, time, trachemys, turbidity, turtle, turtles, variance, verticillata, weed, weighted, wekiva, wekiwa, wssp; Wekiwa Springs State Park ( local )
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hrycyshyn, G. E. (2007). Survival Probabilities and Density of Four Sympatric Species of Freshwater Turtles in Florida. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0021036
Chicago Manual of Style (16th Edition):
Hrycyshyn, Gabrielle E. “Survival Probabilities and Density of Four Sympatric Species of Freshwater Turtles in Florida.” 2007. Masters Thesis, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0021036.
MLA Handbook (7th Edition):
Hrycyshyn, Gabrielle E. “Survival Probabilities and Density of Four Sympatric Species of Freshwater Turtles in Florida.” 2007. Web. 16 Jan 2021.
Vancouver:
Hrycyshyn GE. Survival Probabilities and Density of Four Sympatric Species of Freshwater Turtles in Florida. [Internet] [Masters thesis]. University of Florida; 2007. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0021036.
Council of Science Editors:
Hrycyshyn GE. Survival Probabilities and Density of Four Sympatric Species of Freshwater Turtles in Florida. [Masters Thesis]. University of Florida; 2007. Available from: https://ufdc.ufl.edu/UFE0021036

University of Florida
6.
Bohrmann,Thomas F.
Efficient Sampling and Robust Abundance Estimation in Depletion Surveys.
Degree: PhD, Interdisciplinary Ecology, 2011, University of Florida
URL: https://ufdc.ufl.edu/UFE0043262
► Surveys of animal abundance are central to the conservation and management of living natural resources. However, many species complicate the sampling process because of detection…
(more)
▼ Surveys of animal abundance are central to the conservation and management of living natural resources. However, many species complicate the sampling process because of detection uncertainty. One sampling method employed to deal with this problem is depletion (or removal) surveys in which animals are sequentially removed (and not replaced) from a closed subunit of the population. The pattern of decline in catches in successive removals provides simultaneous information about the capture or detection probability (which we call catchability) and the abundance process. Our research focuses on two aspects of depletion surveys. First, we describe results and methodology useful in designing efficient surveys of abundance, i.e. learning as much about population abundance as possible for each dollar spent on sampling. Second we describe a novel method for estimation of abundance which includes both the advantages of model-based inference and design-based inference. We show that the coherent combination of these two estimation frameworks yields a useful, robust total abundance estimator. We compare the performance of this ?hybrid? estimator with a fully model-based approach using a simulation study. Throughout we refer to and provide results regarding a data set of depletion surveys of Chesapeake Bay blue crab (Callinectes sapidus) which is part of their annual stock assessment. ( en )
Advisors/Committee Members: Christman, Mary C (committee chair), Bolker, Benjamin M (committee member), Dorazio, Robert (committee member), Allen, Michael S (committee member).
Subjects/Keywords: Crabs; Estimation methods; Estimators; Financial depletion; Modeling; Multilevel models; Parametric models; Population estimates; Simulations; Statistical models; abundance – depletion – removal – survey
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
F, B. (2011). Efficient Sampling and Robust Abundance Estimation in Depletion Surveys. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0043262
Chicago Manual of Style (16th Edition):
F, Bohrmann,Thomas. “Efficient Sampling and Robust Abundance Estimation in Depletion Surveys.” 2011. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0043262.
MLA Handbook (7th Edition):
F, Bohrmann,Thomas. “Efficient Sampling and Robust Abundance Estimation in Depletion Surveys.” 2011. Web. 16 Jan 2021.
Vancouver:
F B. Efficient Sampling and Robust Abundance Estimation in Depletion Surveys. [Internet] [Doctoral dissertation]. University of Florida; 2011. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0043262.
Council of Science Editors:
F B. Efficient Sampling and Robust Abundance Estimation in Depletion Surveys. [Doctoral Dissertation]. University of Florida; 2011. Available from: https://ufdc.ufl.edu/UFE0043262

University of Florida
7.
Roy, Vivekananda.
Theoretical and Methodological Developments for Markov Chain Monte Carlo Algorithms for Bayesian Regression.
Degree: PhD, Statistics, 2008, University of Florida
URL: https://ufdc.ufl.edu/UFE0022377
► I develop theoretical and methodological results for Markov chain Monte Carlo (MCMC) algorithms for two different Bayesian regression models. First, I consider a probit regression…
(more)
▼ I develop theoretical and methodological results for Markov chain Monte Carlo (MCMC) algorithms for two different Bayesian regression models. First, I consider a probit regression problem in which Y
1,\dots,Y
n are independent Bernoulli random variables such that \Pr(Y
i =1) = Φ(x
iT β) where x
i is a p-dimensional vector of known covariates associated with Y
i, β is a p-dimensional vector of unknown regression coefficients and Φ(∙) denotes the standard normal distribution function. I study two frequently used MCMC algorithms for exploring the intractable posterior density that results when the probit regression likelihood is combined with a flat prior on β. These algorithms are Albert and Chib's data augmentation algorithm and Liu and Wu's PX-DA algorithm. I prove that both of these algorithms converge at a geometric rate, which ensures the existence of central limit theorems (CLTs) for ergodic averages under a second moment condition. While these two algorithms are essentially equivalent in terms of computational complexity, I show that the PX-DA algorithm is theoretically more efficient in the sense that the asymptotic variance in the CLT under the PX-DA algorithm is no larger than that under Albert and Chib's algorithm. A simple, consistent estimator of the asymptotic variance in the CLT is constructed using regeneration. As an illustration, I apply my results to van Dyk and Meng's lupus data. In this particular example, the estimated asymptotic relative efficiency of the PX-DA algorithm with respect to Albert and Chib's algorithm is about 65, which demonstrates that huge gains in efficiency are possible by using PX-DA. Second, I consider multivariate regression models where the distribution of the errors is a scale mixture of normals. Let π denote the posterior density that results when the likelihood of n observations from the corresponding regression model is combined with the standard non-informative prior. I provide necessary and sufficient condition for the propriety of the posterior distribution, π. I develop two MCMC algorithms that can be used to explore the intractable density π. These algorithms are the data augmentation algorithm and the Haar PX-DA algorithm. I compare the two algorithms in terms of efficiency ordering. I establish drift and minorization conditions to study the convergence rates of these algorithms. ( en )
Advisors/Committee Members: Hobert, James P. (committee chair), Doss, Hani (committee member), Presnell, Brett D. (committee member), Bolker, Benjamin M. (committee member).
Subjects/Keywords: Consistent estimators; Ergodic theory; Markov chains; Mathematical theorems; Matrices; Perceptron convergence procedure; Regression analysis; Simulations; Statistical discrepancies; Statistics; bayesian, da, efficiency, markov, monte, multivariate, probit, px, regenerative
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Roy, V. (2008). Theoretical and Methodological Developments for Markov Chain Monte Carlo Algorithms for Bayesian Regression. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0022377
Chicago Manual of Style (16th Edition):
Roy, Vivekananda. “Theoretical and Methodological Developments for Markov Chain Monte Carlo Algorithms for Bayesian Regression.” 2008. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0022377.
MLA Handbook (7th Edition):
Roy, Vivekananda. “Theoretical and Methodological Developments for Markov Chain Monte Carlo Algorithms for Bayesian Regression.” 2008. Web. 16 Jan 2021.
Vancouver:
Roy V. Theoretical and Methodological Developments for Markov Chain Monte Carlo Algorithms for Bayesian Regression. [Internet] [Doctoral dissertation]. University of Florida; 2008. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0022377.
Council of Science Editors:
Roy V. Theoretical and Methodological Developments for Markov Chain Monte Carlo Algorithms for Bayesian Regression. [Doctoral Dissertation]. University of Florida; 2008. Available from: https://ufdc.ufl.edu/UFE0022377

University of Florida
8.
Rios, Alfredo.
Land Use, Spatial Ecology and Control of the Andean Potato Weevil in the Central Andes of Peru.
Degree: PhD, Interdisciplinary Ecology, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0041218
► This dissertation assessed the potential adoption, and the inhibiting constraints to adoption, of non-pesticide crop protection technologies in Andean livelihood systems and the effects of…
(more)
▼ This dissertation assessed the potential adoption, and the inhibiting constraints to adoption, of non-pesticide crop protection technologies in Andean livelihood systems and the effects of land use intensification (due to continuous cropping, improved varieties and shorter interfield distances) on the distribution of the Andean potato weevil. A survey indicated that plating a second year of potato was not problematic as farmers still obtained reasonable yields and moderate potato damages. Early harvest of improved potato due to market conditions, which accounts for most second year fields, was a factor to control damage, while the decomposition of weeds and grasses supported fertility the second year. Potato fields were infested at least twice as often as fields rotated from potato (even with volunteer potatoes) and fallow fields. An important weevil edge effect makes these areas good targets for eradication. A sampling design to estimate overwintering populations was developed and allows better assessment. Tubers that are farther from the plant stem in a direction perpendicular to the hill were less likely to become infested making this a potential research topic by plant breeders and emphasizes the importance of changes in potato cultivars on weevil densities. The study of weevil movement predicted that closer-spaced fields due to agricultural intensification and climatic conditions should increase the colonization potential of the Andean potato weevil. A better understanding of constraints to adoption is necessary for the design of appropriate alternatives that ameliorate the effects of intensification. Further, different farm household compositions affect the adoption of crop protection differently. The most important characteristic for crop protection was damage reduction and the benefits changed with the producer/consumer ratios in the life cycle of the peasant household. Consideration of this characteristic will allow designing more effective crop protection technologies. ( en )
Advisors/Committee Members: Hildebrand, Peter E. (committee chair), Bolker, Benjamin M. (committee member), McSorley, Robert (committee member), Ortiz, Oscar E. (committee member).
Subjects/Keywords: Cash; Crops; Farmers; Infestation; Insecticides; Pests; Planting; Potatoes; Tubers; Weevils; andean, dispersal, landscape, mantaro, peru, pest, potato, premnotrypes, suturicallus, weevil
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Manager
APA (6th Edition):
Rios, A. (2010). Land Use, Spatial Ecology and Control of the Andean Potato Weevil in the Central Andes of Peru. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0041218
Chicago Manual of Style (16th Edition):
Rios, Alfredo. “Land Use, Spatial Ecology and Control of the Andean Potato Weevil in the Central Andes of Peru.” 2010. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0041218.
MLA Handbook (7th Edition):
Rios, Alfredo. “Land Use, Spatial Ecology and Control of the Andean Potato Weevil in the Central Andes of Peru.” 2010. Web. 16 Jan 2021.
Vancouver:
Rios A. Land Use, Spatial Ecology and Control of the Andean Potato Weevil in the Central Andes of Peru. [Internet] [Doctoral dissertation]. University of Florida; 2010. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0041218.
Council of Science Editors:
Rios A. Land Use, Spatial Ecology and Control of the Andean Potato Weevil in the Central Andes of Peru. [Doctoral Dissertation]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0041218

University of Florida
9.
Bustamante, Dulce.
Culex nigripalpus (Diptera Culicidae) population age structure under heterogeneous environments and sources of error on the estimation of mosquito infection rates.
Degree: PhD, Entomology and Nematology, 2009, University of Florida
URL: https://ufdc.ufl.edu/UFE0041128
► The monitoring of mosquito populations within an arbovirus surveillance program relies on a good understanding of the processes that drive the dynamics of the population.…
(more)
▼ The monitoring of mosquito populations within an arbovirus surveillance program relies on a good understanding of the processes that drive the dynamics of the population. The main goals of this study were to help improve our understanding of the causes of variation in the age structure of mosquitoes and study the factors that affect our ability to estimate and interpret mosquito infection rates in the field. The mosquito Culex nigripalpus is one of the most important vectors of arboviruses in
Florida. The results of a field and a modeling study that investigated environmental causes of variation in the age structure of Cx. nigripalpus are presented here. Age structure is of epidemiological importance because only a subset of mosquitoes will be capable of transmitting virus and this depends on an interaction between physiological and calendar age. The field study results supported that dry periods followed by heavy rains could cause important increases in the proportion of parous females that could be potentially infected and looking for a bloodmeal. In contrast, the proportion of parous females declines 7-14 days after heavy rains due to the emergence of young mosquitoes. The modeling study suggested that mosquito behavior, weather, and landscape complexity are all important factors that introduce variability in the chronological age distribution of unfed parous females. There was more variability in age and older ages became more common, when weather conditions were dry or cool, when mosquitoes were assumed to be less efficient in finding resources, and when the landscape was more complex. Environmental changes have the potential to modify Cx. nigripalpus age structure, but more research is needed on how mosquito behavior affects age distribution. Biological factors such as daily mosquito survival and virus titer variation in mosquitoes introduce errors in estimates of infection and hinder their use as surveillance indicators. Methodological aspects such as sample size and type of viral assay also introduce biases that result in frequent underestimation of the true arboviral infection rate in a mosquito population. Age variability in mosquitoes has environmental and behavioral causes which deserve further study. ( en )
Advisors/Committee Members: Lord, Cynthia C. (committee chair), Day, Jonathan F. (committee member), Lounibos, Leon P. (committee member), Bolker, Benjamin M. (committee member).
Subjects/Keywords: Age structure; Female animals; Infections; Modeling; Oviposition sites; Population dynamics; Population estimates; Population size; Population structure; Rain; age, chronological, culex, florida, infection, model, physiological; City of Vero Beach ( local )
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APA (6th Edition):
Bustamante, D. (2009). Culex nigripalpus (Diptera Culicidae) population age structure under heterogeneous environments and sources of error on the estimation of mosquito infection rates. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0041128
Chicago Manual of Style (16th Edition):
Bustamante, Dulce. “Culex nigripalpus (Diptera Culicidae) population age structure under heterogeneous environments and sources of error on the estimation of mosquito infection rates.” 2009. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0041128.
MLA Handbook (7th Edition):
Bustamante, Dulce. “Culex nigripalpus (Diptera Culicidae) population age structure under heterogeneous environments and sources of error on the estimation of mosquito infection rates.” 2009. Web. 16 Jan 2021.
Vancouver:
Bustamante D. Culex nigripalpus (Diptera Culicidae) population age structure under heterogeneous environments and sources of error on the estimation of mosquito infection rates. [Internet] [Doctoral dissertation]. University of Florida; 2009. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0041128.
Council of Science Editors:
Bustamante D. Culex nigripalpus (Diptera Culicidae) population age structure under heterogeneous environments and sources of error on the estimation of mosquito infection rates. [Doctoral Dissertation]. University of Florida; 2009. Available from: https://ufdc.ufl.edu/UFE0041128

University of Florida
10.
Padmanabha, Harish.
Interactions of Temperature with the Dynamics of Aedes Aegypti (l.) Development in Household Vessels.
Degree: PhD, Entomology and Nematology, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0041509
► The mosquito Aedes aegypti (L.) transmits dengue and chikungunya viruses among human hosts in cities at temperatures ranging 20-30degC, where it thrives in water that…
(more)
▼ The mosquito Aedes aegypti (L.) transmits dengue and chikungunya viruses among human hosts in cities at temperatures ranging 20-30degC, where it thrives in water that humans store in vessels. Two processes are known to drive the dynamics of A. aegypti production in these habitats: resource limitation and human behavior. Although temperature affects mosquito size and maturation rate, there is little understanding of how temperature may affect the capacity of mosquitoes to develop in food limited, domestic environments. In this dissertation we use modeling, experimental and field approaches to explore the general hypothesis that the effects of human and resource-mediated processes on the size, development rate and pupation success of A. aegypti may be modified across temperature gradients or cities that vary in temperature. We experimentally show that due to increased energy demands, larvae at higher temperature may experience tradeoffs between development rate, size and starvation resistance. Moreover, our model of growth and energy storage in mosquitoes indicates that these tradeoffs can both explain the commonly observed effects of temperature on mosquito size and result in interactive effects of food and temperature on development rate. A food-temperature developmental interaction was morphologically corroborated by analyzing wing and epidermal cell size in experimentally reared A. aegypti. Our data suggest that in resource poor habitats commonly inhabited by urban A. aegypti, development rate may be lower at 24-26degC in comparison to 20-22 or 28-30degC, thereby challenging the fundamental assumptions of widely used temperature-driven models of A. aegypti dynamics. Our field study in dengue endemic areas of Colombia indicates that the outcome of this food-temperature interaction depends on specific household behaviors, including the frequency of using, emptying and placing lids on domestic water. Moreover, each of these acts in the context of particular socio-cultural perceptions, altitude, urban architecture and water supply. Nonetheless, our data suggest that climate-induced decreases in water security predicted throughout Colombia may indirectly increase A. aegypti abundance through changes in human behavior. These results demonstrate the underlying interactions between human and mosquito responses to a changing environment and enhancing our capacity to predict A. aegypti production and design locally adapted intervention strategies. ( en )
Advisors/Committee Members: Lounibos, Leon P. (committee chair), Rey, Jorge (committee member), Lord, Cynthia C. (committee member), Bolker, Benjamin M. (committee member).
Subjects/Keywords: Energy storage; Food; Larvae; Modeling; Parametric models; Pupation; Starvation; Temperature resistance; Water temperature; Water usage; aegypti, behavior, cell, chikungunya, climate, dengue, ecology, energetics, human, metabolism, model, resources, size, temperature, vector
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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APA (6th Edition):
Padmanabha, H. (2010). Interactions of Temperature with the Dynamics of Aedes Aegypti (l.) Development in Household Vessels. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0041509
Chicago Manual of Style (16th Edition):
Padmanabha, Harish. “Interactions of Temperature with the Dynamics of Aedes Aegypti (l.) Development in Household Vessels.” 2010. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0041509.
MLA Handbook (7th Edition):
Padmanabha, Harish. “Interactions of Temperature with the Dynamics of Aedes Aegypti (l.) Development in Household Vessels.” 2010. Web. 16 Jan 2021.
Vancouver:
Padmanabha H. Interactions of Temperature with the Dynamics of Aedes Aegypti (l.) Development in Household Vessels. [Internet] [Doctoral dissertation]. University of Florida; 2010. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0041509.
Council of Science Editors:
Padmanabha H. Interactions of Temperature with the Dynamics of Aedes Aegypti (l.) Development in Household Vessels. [Doctoral Dissertation]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0041509

University of Florida
11.
Griswold, Marcus.
Riparian Zone Management in Coastal Plain Streams Multi-Scale Effects of Habitat Fragmentation.
Degree: PhD, Environmental Engineering Sciences, 2008, University of Florida
URL: https://ufdc.ufl.edu/UFE0022401
► Riparian zones act as filters for nutrients and sediment, and provide food and habitat for terrestrial and aquatic organisms. Preserving riparian structure in headwater streams…
(more)
▼ Riparian zones act as filters for nutrients and sediment, and provide food and habitat for terrestrial and aquatic organisms. Preserving riparian structure in headwater streams is critical to protecting local and downstream aquatic biota. Forestry practices along streams are capable of degrading riparian zone function, leading to increased sediment and nutrient inputs, limiting organic matter availability, and altering light and temperature levels in streams. The effects of forestry practices on aquatic invertebrate communities were evaluated in coastal plain streams by experimentally manipulating two harvest regimes in headwater streams based on Georgia?s best management practices. Though the primary goal of the study was to relate anthropogenic disturbances to water quality, a drought occurring prior to the study created degraded streams with low invertebrate abundance and diversity. The drought resulted in streambeds with large amounts of stored organic matter and nutrients, that became available with re-wetting. A core set of species appeared immediately following drought in the streams, reflecting a shared species pool. These species shared resilient traits, including short life cycles and resistance to desiccation, which allowed for rapid recovery from disturbance. However, temporal shifts in biological traits reflected a more stable hydrologic regime over time. As communities recovered, a shift occurred from individuals that were small, sclerotized, and abundant in drift, to those that were larger, soft-bodied, and rare in drift, indicating that the habitat was more favorable. Thus, such shifts in trait structure and the role of natural disturbances need to be accounted for when bioassessment programs are implemented. To evaluate the effects of logging on streams, macroinvertebrates were sampled in reference and harvest streams before and after an experimental harvest. In response to harvest, communities shifted from detritivores to herbivores, following a shift in the food source from organic matter to algae and macrophytes. This change was most apparent in the thinned SMZ, where chlorophyll a was 50-100% higher than in the intact SMZ and reference streams. In general, changes in community structure were most apparent the first year following the harvest and began to follow a trajectory of recovery over the next four years. Interestingly, multimetric indices of water quality based on macroinvertebrates suggested more favorable conditions in the most disturbed treatment (Thinned SMZ). This relates to increases in food quality, due to an increase in algae and macrophytes, and a decrease in C:N ratios in terrestrially derived leaves. However, invertebrates in the thinned SMZ were represented by species preferring to live in sand, highlighting the increased isolation of patches apparent in these reaches. Observational and experimental field work was used to determine the effects of altered habitat amount and type on macroinvertebrate colonization and movement patterns. Macrophyte patches were more complex,…
Advisors/Committee Members: Crisman, Thomas L. (committee chair), Holt, Robert D. (committee member), Wise, William R. (committee member), Bolker, Benjamin M. (committee member).
Subjects/Keywords: Drought; Ecology; Fresh water; Invertebrates; Landscapes; Macroinvertebrates; Macrophytes; Species; Streams; Watersheds; bmp, drought, forestry, logging, macroinvertebrates, quality, riparian, water; City of Tallahassee ( local )
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Griswold, M. (2008). Riparian Zone Management in Coastal Plain Streams Multi-Scale Effects of Habitat Fragmentation. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0022401
Chicago Manual of Style (16th Edition):
Griswold, Marcus. “Riparian Zone Management in Coastal Plain Streams Multi-Scale Effects of Habitat Fragmentation.” 2008. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0022401.
MLA Handbook (7th Edition):
Griswold, Marcus. “Riparian Zone Management in Coastal Plain Streams Multi-Scale Effects of Habitat Fragmentation.” 2008. Web. 16 Jan 2021.
Vancouver:
Griswold M. Riparian Zone Management in Coastal Plain Streams Multi-Scale Effects of Habitat Fragmentation. [Internet] [Doctoral dissertation]. University of Florida; 2008. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0022401.
Council of Science Editors:
Griswold M. Riparian Zone Management in Coastal Plain Streams Multi-Scale Effects of Habitat Fragmentation. [Doctoral Dissertation]. University of Florida; 2008. Available from: https://ufdc.ufl.edu/UFE0022401

University of Florida
12.
White, Jada-Simone.
Indirect effects of a marine ecosystem engineer alter the abundance and distribution of foundation coral species.
Degree: PhD, Zoology, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0041612
► Farmerfish engineer coral communities by facilitating algal turf and exerting resource control through territorial defense: Within territories, these behaviors indirectly (1) increase interactions between coral…
(more)
▼ Farmerfish engineer coral communities by facilitating algal turf and exerting resource control through territorial defense: Within territories, these behaviors indirectly (1) increase interactions between coral and farmed turf and (2) decrease interactions with mobile grazers. A small-scale experiment indicated massive Porites were more vulnerable to competition with turf, than were branching Acropora, encrusting Montipora, or lobed Pocillopora. In contrast, the more delicate acroporids (Acropora and Montipora), were more vulnerable to predation by mobile corallivores and grew and survived better in the presence of S. nigricans defense. I used a more realistic manipulation of turf, sediment, and sediment-consuming vermetid snails to document the rate of massive Porites overgrowth by S. nigricans-associated turf. I addressed the indirect effects of territoriality in a demographic context using size specific population monitoring of two of the four genera, Acropora and Pocillopora, in the presence and removal of S. nigricans. It appears the disturbance history has played a pivotal role in the types of community changes observed: While S. nigricans usually colonizes Acropora thickets, a series of disturbances virtually eliminated these habitats and farmerfish are found colonizing the dominant disturbance tolerant, but turf sensitive, massive Porites. Taxa with a higher resistance to competition with turf can utilize dead portions of these massive corals. This increase in substrate availability, when coupled with lower mortality rates, has led to enhanced recovery of branching corals within farmerfish territories. Corymbose Acropora are relegated to high flow, or cracks and crevices, outside S. nigricans territories, suggesting grazing pressure is constraining recovery in the absence of this ecosystem engineer. Pocillopora also enjoys lower mortality inside S. nigricans territories, though susceptibility to losses by corallivorous fishes was lower than those attributed to a periodic outbreak of the crown-o-thorn seastar, Acanthaster planci. This system supports the idea that disturbance can alter the engineering role: S. nigricans adversely affects branching Acropora in relatively undisturbed habitats, but can offer a less stressful environment if predation pressure by corallivores is high. These results suggest that corallivory may sometimes function as an important regulatory process of coral community structure and warrants additional research. In particular, whether the observed high predation rates are driven by changes in top-down (e.g., trophic cascades induced by anthropogenic removal of top predators), or bottom-up processes (e.g., changes in grazing pressure due to alterations in coral and algal community structure following natural disturbances). ( en )
Advisors/Committee Members: Bolker, Benjamin M. (committee chair), St. Mary, Colette M. (committee member), Silliman, Brian (committee member), Bjorndal, Karen (committee member), Lindberg, William J. (committee member).
Subjects/Keywords: Algae; Coral reefs; Corals; Ecology; Fish; Mortality; Predation; Reefs; Sediments; Species; acropora, algae, competition, coral, corallivory, dynamics, ecosystem, engineer, farmerfish, herbivory, keystone, montipora, nigricans, pocillopora, population, porites, resilience, species, stegastes
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
White, J. (2010). Indirect effects of a marine ecosystem engineer alter the abundance and distribution of foundation coral species. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0041612
Chicago Manual of Style (16th Edition):
White, Jada-Simone. “Indirect effects of a marine ecosystem engineer alter the abundance and distribution of foundation coral species.” 2010. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0041612.
MLA Handbook (7th Edition):
White, Jada-Simone. “Indirect effects of a marine ecosystem engineer alter the abundance and distribution of foundation coral species.” 2010. Web. 16 Jan 2021.
Vancouver:
White J. Indirect effects of a marine ecosystem engineer alter the abundance and distribution of foundation coral species. [Internet] [Doctoral dissertation]. University of Florida; 2010. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0041612.
Council of Science Editors:
White J. Indirect effects of a marine ecosystem engineer alter the abundance and distribution of foundation coral species. [Doctoral Dissertation]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0041612

University of Florida
13.
Valle, Denis.
Assessing Uncertainty in Forest Dynamic Models A Case Study Using SYMFOR.
Degree: MS, Forest Resources and Conservation, 2008, University of Florida
URL: https://ufdc.ufl.edu/UFE0022389
► Despite its local, regional and global importance, the Amazon forest faces multiple threats. Forest dynamic models have been widely used to evaluate the impact of…
(more)
▼ Despite its local, regional and global importance, the Amazon forest faces multiple threats. Forest dynamic models have been widely used to evaluate the impact of a number of anthropogenic impacts on the forest, such as timber logging and climate change. I hypothesize that these models, however, have usually failed to report the full uncertainty associated with their projections. I analyzed two commonly used assumptions in forest modeling: dynamic equilibrium assumption and maximum size assumption. I then quantified four sources of model uncertainty using the tropical forest simulation model SIMFLORA: model stochasticity, parameter uncertainty, starting condition effect, and modeling assumptions. My results suggest that modeling assumptions, a commonly neglected source of uncertainty, can have a greater effect than other sources of uncertainty that are more commonly taken into account, such as parameter uncertainty, particularly when assumptions are used to deal with sub-model extrapolations. Also, to reduce assumption uncertainty in particular, and overall model uncertainty in general, it is of fundamental importance to use the available data to determine the probability of each model (i.e., data are used to evaluate the different assumptions adopted in the modeling process). Furthermore, targeted experimental studies are crucial to generate data that can be used to avoid the use of some of these assumptions. Using SIMFLORA as a case study, my results indicate that the overall modeling uncertainty is likely to be underestimated if all four sources listed above are not simultaneously considered. Finally, the method developed in this thesis to partition overall variance of the mean into different uncertainty sources can be applied to quantify the uncertainty of other models, not restricted to forest dynamic models. ( en )
Advisors/Committee Members: Staudhammer, Christina Lynn (committee chair), Cropper, Wendell P. (committee member), Putz, Francis E. (committee member), Bolker, Benjamin M. (committee member), Young, Linda (committee member).
Subjects/Keywords: Ecological modeling; Forests; Logging; Modeling; Mortality; Parametric models; Simulations; Statistical discrepancies; Stochastic models; Trees; amazon, forest, multimodel, simulation, uncertainty, variance
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Valle, D. (2008). Assessing Uncertainty in Forest Dynamic Models A Case Study Using SYMFOR. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0022389
Chicago Manual of Style (16th Edition):
Valle, Denis. “Assessing Uncertainty in Forest Dynamic Models A Case Study Using SYMFOR.” 2008. Masters Thesis, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0022389.
MLA Handbook (7th Edition):
Valle, Denis. “Assessing Uncertainty in Forest Dynamic Models A Case Study Using SYMFOR.” 2008. Web. 16 Jan 2021.
Vancouver:
Valle D. Assessing Uncertainty in Forest Dynamic Models A Case Study Using SYMFOR. [Internet] [Masters thesis]. University of Florida; 2008. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0022389.
Council of Science Editors:
Valle D. Assessing Uncertainty in Forest Dynamic Models A Case Study Using SYMFOR. [Masters Thesis]. University of Florida; 2008. Available from: https://ufdc.ufl.edu/UFE0022389

University of Florida
14.
Bhattacharya,Souvik.
Oscillations in a Size-Structured Prey Predator Model.
Degree: PhD, Mathematics, 2011, University of Florida
URL: https://ufdc.ufl.edu/UFE0043216
► This dissertation introduces a predator-prey model with the prey structured by body size based on reports in the literature that predation rates are prey-size specific.…
(more)
▼ This dissertation introduces a predator-prey model with the prey structured by body size based on reports in the literature that predation rates are prey-size specific. The model is built on the foundation of the one-species physiologically structured models studied earlier. Three types of equilibria are found: extinction, multiple prey-only equilibria and possibly multiple predator-prey coexistence equilibria. The stabilities of the equilibria are investigated. Comparison is made with the underlying ODE Lotka-Volterra model. It turns out that the ODE model can exhibit sustain oscillations if there is an Allee effect in the net reproduction rate, that is the net reproduction rate grows for some range of the prey's population size. In contrast, it is shown that the structured PDE model can exhibit sustain oscillations even if the net reproductive rate is strictly declining. Those occur, however, if reproduction is size specifc and limited to individuals of large enough size. Simulations are presented to support our hypothesis that size-specifc predation can destabilize the predator-prey equilibrium in the PDE model. ( en )
Advisors/Committee Members: Martcheva-Drashanska, Maia (committee chair), Rao, Murali (committee member), Hager, William W (committee member), Yan, Liqing (committee member), Bolker, Benjamin M (committee member).
Subjects/Keywords: Birth rates; Body size; Ecology; Equation roots; Method of characteristics; Modeling; Mortality; Population size; Predation; Predators
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Bhattacharya,Souvik. (2011). Oscillations in a Size-Structured Prey Predator Model. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0043216
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Chicago Manual of Style (16th Edition):
Bhattacharya,Souvik. “Oscillations in a Size-Structured Prey Predator Model.” 2011. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0043216.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
MLA Handbook (7th Edition):
Bhattacharya,Souvik. “Oscillations in a Size-Structured Prey Predator Model.” 2011. Web. 16 Jan 2021.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Vancouver:
Bhattacharya,Souvik. Oscillations in a Size-Structured Prey Predator Model. [Internet] [Doctoral dissertation]. University of Florida; 2011. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0043216.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Council of Science Editors:
Bhattacharya,Souvik. Oscillations in a Size-Structured Prey Predator Model. [Doctoral Dissertation]. University of Florida; 2011. Available from: https://ufdc.ufl.edu/UFE0043216
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

University of Florida
15.
Clark, Connie.
Factors that Determine Patterns of Seedling Recruitment in an Afrotropical Forest.
Degree: PhD, Interdisciplinary Ecology, 2009, University of Florida
URL: https://ufdc.ufl.edu/UFE0024894
► FACTORS THAT DETERMINE PATTERNS OF SEEDLING RECRUITMENT IN AN AFROTROPICAL FOREST Tropical forests account for nearly 50% of all known species. Very little is understood…
(more)
▼ FACTORS THAT DETERMINE PATTERNS OF SEEDLING RECRUITMENT IN AN AFROTROPICAL FOREST Tropical forests account for nearly 50% of all known species. Very little is understood about the processes that maintain or promote such diversity. Theoretical models suggest that processes limiting recruitment of new individuals into populations may be key to maintaining species diversity. By keeping population numbers of more competitive species in check, recruitment limitation should allow greater numbers of species to co-exist. Two opposing hypotheses have been proposed to explain how recruitment limitation might influence tropical tree diversity; the seed limitation hypothesis and the establishment limitation hypothesis. These hypotheses are generally treated as mutually exclusive, and evidence of either is used to bolster competing theories of community composition that are tightly associated with each. In chapter 1, I develop a framework that views seed and establishment limitation as processes that occur at opposite ends of a continuum. I adopt this framework in a meta-analysis to assess the relative strength of seed and establishment limitation across a range of plant systems. I find that most species are seed limited, though the effects of seed addition are typically small. Establishment, on average, proves to be a stronger limiting force for most plants. I provide recommendations to improve experimental approaches used to examine the relative strength of these two processes. Chapter 2 applies these recommendations to a large scale experiment designed to tease apart the roles of seed and establishment limitation for five randomly-chosen tree species in an Afrotropical forest. I conclude that though seed limitation is relatively weak, it can balance the exclusion process of competition and niche partitioning at very high levels of seed arrival. Yet, niche-based, post dispersal processes more importantly limit seedling recruitment than seed arrival. Chapter 3 delves into the mechanisms responsible for post dispersal seed and seedling mortality. I evaluate the strength and relative importance light availability, soil fertility, competition, density- and distance-dependence, seed predation and herbivory at two stages of seedling recruitment. I conclude that seedling recruitment in the Congo Basin is most strongly dictated by generalist vertebrate seed predators and herbivores, with relatively weaker abiotic environmental filtering and density-dependence playing secondary roles. ( en )
Advisors/Committee Members: Levey, Douglas J. (committee chair), Holt, Robert D. (committee member), Robinson, Scott K. (committee member), Bolker, Benjamin M. (committee member), Kitajima, Kaoru (committee member).
Subjects/Keywords: Density; Ecology; Forest trees; Forests; Mortality; Seedling emergence; Seedlings; Seeds; Species; Trees; africa, establishment, forest, light, limitation, metaanalysis, niche, recruitment, seed, seedling, soil, tropics
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Clark, C. (2009). Factors that Determine Patterns of Seedling Recruitment in an Afrotropical Forest. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0024894
Chicago Manual of Style (16th Edition):
Clark, Connie. “Factors that Determine Patterns of Seedling Recruitment in an Afrotropical Forest.” 2009. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0024894.
MLA Handbook (7th Edition):
Clark, Connie. “Factors that Determine Patterns of Seedling Recruitment in an Afrotropical Forest.” 2009. Web. 16 Jan 2021.
Vancouver:
Clark C. Factors that Determine Patterns of Seedling Recruitment in an Afrotropical Forest. [Internet] [Doctoral dissertation]. University of Florida; 2009. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0024894.
Council of Science Editors:
Clark C. Factors that Determine Patterns of Seedling Recruitment in an Afrotropical Forest. [Doctoral Dissertation]. University of Florida; 2009. Available from: https://ufdc.ufl.edu/UFE0024894

University of Florida
16.
Perez-Heydrich, Carol.
Ecological Investigations of Mycoplasmal Upper Respiratory Tract Disease in Natural Populations of Threatened Gopher Tortoises Insights from Population Ecology, Mathematical Epidemiology, and Behavioral Ecology.
Degree: PhD, Veterinary Medical Sciences - Veterinary Medicine, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0041131
► Disease is a major conservation concern for imperiled wildlife populations. While a comprehensive understanding of wildlife disease in natural systems requires cross-disciplinary insights (i.e., microbiology,…
(more)
▼ Disease is a major conservation concern for imperiled wildlife populations. While a comprehensive understanding of wildlife disease in natural systems requires cross-disciplinary insights (i.e., microbiology, veterinary medicine, epidemiology, population ecology, and behavioral ecology, among others), I focus here on ecological and epidemiological methods. Using mycoplasmal upper respiratory tract disease (URTD) in natural gopher tortoise (Gopherus polyphemus) populations as a study system, the specific objectives of this dissertation were to (1) elucidate potential long-term impacts of URTD on host population dynamics, (2) identify and quantify mechanisms driving observed stage-specific seroprevalence patterns in exposed populations, and (3) describe how movement-associated behavior can contribute to infection susceptibility at the individual-level. Specifically, through the implementation of commonly used matrix models from population ecology, I projected the potential effects of recurring mycoplasmal URTD epizootics on the long-term dynamics of gopher tortoise populations. I solely focused on the impacts of URTD-mediated mortality events, although morbidity effects can also be important in other chronic respiratory mycoplasmal infections. I determined that host demographic factors (i.e., survival, growth, and fecundity) were more important than disease-associated factors (i.e., force of infection, disease-induced mortality, outbreak duration, and outbreak frequency) on the long-term dynamics of exposed host populations, and that the largest impacts of disease were associated with the overall frequency of outbreaks and disease-induced mortality rates. Additionally, by fitting force of infection models to age-seroprevalence data, I determined that the most biologically plausible explanation for observed seroprevalence patterns involved stage-specific force of infection rates and negligible disease-induced mortality. This is consistent with other chronic respiratory mycoplasmal infections that are characterized by low mortality but high morbidity. Lastly, through the use of regression analyses and observed individual movement patterns, I attempted to quantify the risk of infection associated with individual behaviors. Movement-associated behavior, along with sex and site classification, was found to be significantly associated with individual infection status; however, this association was most likely a retro-causal one, whereby infected tortoises were more likely to exhibit foraging and basking behavior than mate-seeking behavior. Overall, the three studies comprising this dissertation provided insights into the epizootiology of mycoplasmal URTD in natural gopher tortoise populations, and its potential impacts on long-term host population dynamics. ( en )
Advisors/Committee Members: Brown, Mary B. (committee chair), Brown, Daniel R. (committee member), Forrester, Donald J. (committee member), Bolker, Benjamin M. (committee member), Oli, Madan K. (committee member).
Subjects/Keywords: Disease models; Disease outbreaks; Diseases; Gophers; Infections; Mortality; Population dynamics; Population estimates; Tortoises; Wildlife; disease, models, mycoplasma, population, tortoise, wildlife; City of Tallahassee ( local )
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APA (6th Edition):
Perez-Heydrich, C. (2010). Ecological Investigations of Mycoplasmal Upper Respiratory Tract Disease in Natural Populations of Threatened Gopher Tortoises Insights from Population Ecology, Mathematical Epidemiology, and Behavioral Ecology. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0041131
Chicago Manual of Style (16th Edition):
Perez-Heydrich, Carol. “Ecological Investigations of Mycoplasmal Upper Respiratory Tract Disease in Natural Populations of Threatened Gopher Tortoises Insights from Population Ecology, Mathematical Epidemiology, and Behavioral Ecology.” 2010. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0041131.
MLA Handbook (7th Edition):
Perez-Heydrich, Carol. “Ecological Investigations of Mycoplasmal Upper Respiratory Tract Disease in Natural Populations of Threatened Gopher Tortoises Insights from Population Ecology, Mathematical Epidemiology, and Behavioral Ecology.” 2010. Web. 16 Jan 2021.
Vancouver:
Perez-Heydrich C. Ecological Investigations of Mycoplasmal Upper Respiratory Tract Disease in Natural Populations of Threatened Gopher Tortoises Insights from Population Ecology, Mathematical Epidemiology, and Behavioral Ecology. [Internet] [Doctoral dissertation]. University of Florida; 2010. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0041131.
Council of Science Editors:
Perez-Heydrich C. Ecological Investigations of Mycoplasmal Upper Respiratory Tract Disease in Natural Populations of Threatened Gopher Tortoises Insights from Population Ecology, Mathematical Epidemiology, and Behavioral Ecology. [Doctoral Dissertation]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0041131

University of Florida
17.
Hostetler, Jeffrey.
Estimation of Demographic Parameters and Population Viability Analysis for the Florida Panther.
Degree: PhD, Wildlife Ecology and Conservation, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0042566
► Inbreeding and low genetic diversity can cause reductions in individual fitness and increase extinction risk in animal populations. Introgression, achieved by releasing genetically diverse individuals…
(more)
▼ Inbreeding and low genetic diversity can cause reductions in individual fitness and increase extinction risk in animal populations. Introgression, achieved by releasing genetically diverse individuals into inbred populations, has been used as a conservation tool to improve demographic performance in endangered populations. By the 1980s,
Florida panthers (Puma concolor coryi) had been reduced to a small, inbred population that appeared to be on the brink of extinction. In 1995, female pumas from Texas (P. c. stanleyana) were released in occupied panther range as part of an intentional introgression program to restore genetic variability and improve demographic performance of panthers. We used 25 years (1981-2006) of continuous radio-telemetry and genetic data to estimate and model sub-adult and adult panther survival and cause-specific mortality to provide rigorous sex and age class-specific survival estimates and evaluate the effect of the introgression program on these parameters. Genetic ancestry strongly influenced annual survival of sub-adults and adults after introgression, as F1 generation admixed panthers (s = 0.98) survived better than pre-introgression type panthers (s = 0.77) and other admixed individuals (s = 0.82). Furthermore, heterozygosity was higher for admixed panthers relative to pre-introgression type panthers and positively influenced survival. We used multiple sources of data collected during 1982-2008 and a live-recapture dead-recovery modeling framework to estimate and model survival of
Florida panther kittens (age 0 1 year). Overall, annual survival of
Florida panther kittens was 0.323 +- 0.065 (SE), which was lower than estimates used in previous population models. We found that kitten survival generally increased with degree of admixture: F1 admixed and backcrossed to Texas kittens survived better than canonical
Florida panther and backcrossed to canonical kittens. Average heterozygosity positively influenced kitten and older panther survival, whereas index of panther abundance negatively influenced kitten survival. Our approach to integrate data from multiple sources was effective at improving robustness as well as precision of estimates of
Florida panther kitten survival. We used long-term reproductive data (1995-2008) collected from 61 female
Florida panthers to estimate and model breeding probability (probability of producing a litter) and litter size, and to investigate the influence of intentional introgression on these parameters. Overall, 6-month probability of breeding (+- 1 SE) was 0.232 +- 0.021 and average litter size was 2.60 +- 0.09. Although F1 admixed females had lower breeding probability than females with other ancestries, this was most likely because kittens born to F1 females survive better; consequently, these females are not available for breeding until kittens are independent. There was no evidence for the effect of ancestry on litter size, or of heterozygosity on probability of breeding or litter size. Previous population viability analyses (PVAs) for the
Florida…
Advisors/Committee Members: Oli, Madan K. (committee chair), Sunquist, Melvin E. (committee member), Nichols, James D. (committee member), Bolker, Benjamin M. (committee member), Onorato, David (committee member).
Subjects/Keywords: Age structure; Analytical estimating; Ancestry; Breeding; Everglades; Kittens; Modeling; Panthers; Parametric models; Population estimates; Miami metropolitan area ( local )
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
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APA (6th Edition):
Hostetler, J. (2010). Estimation of Demographic Parameters and Population Viability Analysis for the Florida Panther. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0042566
Chicago Manual of Style (16th Edition):
Hostetler, Jeffrey. “Estimation of Demographic Parameters and Population Viability Analysis for the Florida Panther.” 2010. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0042566.
MLA Handbook (7th Edition):
Hostetler, Jeffrey. “Estimation of Demographic Parameters and Population Viability Analysis for the Florida Panther.” 2010. Web. 16 Jan 2021.
Vancouver:
Hostetler J. Estimation of Demographic Parameters and Population Viability Analysis for the Florida Panther. [Internet] [Doctoral dissertation]. University of Florida; 2010. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0042566.
Council of Science Editors:
Hostetler J. Estimation of Demographic Parameters and Population Viability Analysis for the Florida Panther. [Doctoral Dissertation]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0042566

University of Florida
18.
Poulsen, John.
Logging and Hunting Alter Patterns of Seed Dispersal and Seedling Recruitment in an Afrotropical Forest.
Degree: PhD, Zoology, 2009, University of Florida
URL: https://ufdc.ufl.edu/UFE0024893
► LOGGING AND HUNTING ALTER PATTERNS OF SEED DISPERSAL AND SEEDLING RECRUITMENT IN AN AFROTROPICAL FOREST Unprecedented rates of logging and hunting in Central Africa threaten…
(more)
▼ LOGGING AND HUNTING ALTER PATTERNS OF SEED DISPERSAL AND SEEDLING RECRUITMENT IN AN AFROTROPICAL FOREST Unprecedented rates of logging and hunting in Central Africa threaten to transform vast tracts of primary forest into a mosaic of degraded forest emptied of its animals. Reductions in abundances of seed-dispersing animals are hypothesized to alter patterns of seed deposition for many tree species, potentially limiting forest regeneration with long-term consequences for forest structure and composition. In northern Republic of Congo, I set up a large scale observational experiment to decouple the effects of logging and hunting on animal abundance and seed dispersal patterns by positioning 30 permanent transects, each linked to a 1 ha tree plot, in forest disturbed by logging and hunting, logging alone, and neither logging nor hunting. I found that the effects of hunting and logging on densities of animal guilds outweighed the effects of local forest structure and fruit resources. Logging and hunting sometimes interacted to reduce guild densities (ape, duiker, monkey, and pig) by as much as 71% and shifted the composition of the animal community away from large mammals towards squirrels and birds. With seed trap data collected from the tree plots, I used inverse modeling to quantify seed dispersal patterns of 26 tree species. Hunting reduced mean dispersal distances of animal-dispersed species by at least 20%, while hunting and logging both increased mean dispersal distances and dispersion of wind-dispersed species. To determine if changes in seed dispersal patterns reduce seedling recruitment and survival, I experimentally manipulated seed dispersal patterns under several individuals of a monkey-dispersed tree, creating distributions to mimic scenarios of no dispersal , natural dispersal and good dispersal . After 18 months, good dispersal increased seedling survival by 26% over natural dispersal , whereas no dispersal reduced seedling survival by 78%. Survival of seedlings depended on the density of dispersed seeds but not the distance from the tree. This experiment demonstrated that seed dispersal patterns do matter for seedling recruitment and survival. Management of hunting is a priority for the conservation of tropical forests because forests emptied of their seed dispersers will have limited regeneration capacity. ( en )
Advisors/Committee Members: Bolker, Benjamin M. (committee chair), Kitajima, Kaoru (committee member), Palmer, Todd (committee member), Levey, Douglas J. (committee member), Cropper, Wendell P. (committee member).
Subjects/Keywords: Animals; Birds; Forests; Hunting; Logging; Seed dispersal; Seedlings; Species; Trees; Tropical forests; animal, congo, dispersal, forest, hunting, logging, recruitment, seed, seedling, survival, tropics
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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APA (6th Edition):
Poulsen, J. (2009). Logging and Hunting Alter Patterns of Seed Dispersal and Seedling Recruitment in an Afrotropical Forest. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0024893
Chicago Manual of Style (16th Edition):
Poulsen, John. “Logging and Hunting Alter Patterns of Seed Dispersal and Seedling Recruitment in an Afrotropical Forest.” 2009. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0024893.
MLA Handbook (7th Edition):
Poulsen, John. “Logging and Hunting Alter Patterns of Seed Dispersal and Seedling Recruitment in an Afrotropical Forest.” 2009. Web. 16 Jan 2021.
Vancouver:
Poulsen J. Logging and Hunting Alter Patterns of Seed Dispersal and Seedling Recruitment in an Afrotropical Forest. [Internet] [Doctoral dissertation]. University of Florida; 2009. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0024893.
Council of Science Editors:
Poulsen J. Logging and Hunting Alter Patterns of Seed Dispersal and Seedling Recruitment in an Afrotropical Forest. [Doctoral Dissertation]. University of Florida; 2009. Available from: https://ufdc.ufl.edu/UFE0024893

University of Florida
19.
Crummett, Lisa.
Testing Hypotheses for the Maintenance of Sexual Reproduction in Campeloma limum (gastropoda Viviparidae).
Degree: PhD, Zoology, 2008, University of Florida
URL: https://ufdc.ufl.edu/UFE0023781
► The goal of this study was to examine several hypotheses for the maintenance of sexual reproduction by utilizing a freshwater snail that exhibits both sexual…
(more)
▼ The goal of this study was to examine several hypotheses for the maintenance of sexual reproduction by utilizing a freshwater snail that exhibits both sexual and parthenogenetic reproduction. One of the biggest unsolved questions in evolutionary biology is why are there so many sexual species and so few parthenogenetic species? This question is driven by the ?two-fold cost of sex? phenomena; parthenogenetic females should have twice the reproductive rate as their sexual counterparts and further, an allele that confers parthenogenetic reproduction should spread twice as fast in a population as an allele that confers sexual reproduction. There are numerous modeling studies that attempt to answer the ?maintenance of sex paradox? but far fewer studies that use empirical data from natural populations to approach this evolutionary conundrum. We collected observational and experimental data from sexual and parthenogenetic populations of the freshwater snail, Campeloma limum, to (1) test the assumption that sexual populations exhibit a two-fold cost of sex compared to parthenogenetic populations and (2) test two ecological hypotheses that could explain the maintenance of sexual reproduction in C. limum. First, we compared fecundity and offspring viability in four sexual versus four parthenogenetic C. limum populations and observed that sexual C. limum do exhibit at least a two-fold cost of sex compared to parthenogenetic C. limum, and in some instances, an even greater cost. This finding confirmed that it was appropriate to examine the maintenance of sex paradox in C. limum. Next, we tested the Red Queen Hypothesis for the maintenance of sex, which posits that sexual lineages can escape parasitic infection by having offspring with variable resistance genotypes while parthenogenetic lineages, which have genetically invariant offspring, cannot. Parasite prevalence data from four sexual and four parthenogenetic populations, as well as survivorship data from snail transplant experiments, did not support Red Queen predictions. We then tested the Tangled Bank Hypothesis, which posits that sexual reproduction is favored in populations experiencing intense intraspecific competition in heterogeneous environments. Genetically variable offspring could potentially fill a greater variety of niches than genetically invariant offspring, thereby partitioning available resources and increasing the carrying capacity of a population. We measured population density, adult size as an indicator of resource limitation (intraspecific competition), and water and substrate quality in four sexual and five parthenogenetic populations. Our main findings, extremely low population density in parthenogenetic populations and no evidence of intraspecific competition, do not support the Tangled Bank hypothesis. Alone, our data support a hypothesis for the maintenance of parthenogenesis rather than sex, the Reproductive Assurance Hypothesis. If we combine our findings with genetic data from a previous study of sexual and parthenogenetic C. limum, we provide…
Advisors/Committee Members: Wayne, Marta L. (committee chair), Baer, Charles F. (committee member), Paulay, Gustav (committee member), Bolker, Benjamin M. (committee member), Baker, Shirley M. (committee member).
Subjects/Keywords: Eggs; Embryos; Fecundity; Female animals; Genetic mutation; Parasites; Parthenogenesis; Population density; Sexual reproduction; Snails; asexual, bank, campeloma, evolution, fitness, gastropoda, parasite, parthenogenesis, queen, red, reproduction, sexual, snail, tangled
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Crummett, L. (2008). Testing Hypotheses for the Maintenance of Sexual Reproduction in Campeloma limum (gastropoda Viviparidae). (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0023781
Chicago Manual of Style (16th Edition):
Crummett, Lisa. “Testing Hypotheses for the Maintenance of Sexual Reproduction in Campeloma limum (gastropoda Viviparidae).” 2008. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0023781.
MLA Handbook (7th Edition):
Crummett, Lisa. “Testing Hypotheses for the Maintenance of Sexual Reproduction in Campeloma limum (gastropoda Viviparidae).” 2008. Web. 16 Jan 2021.
Vancouver:
Crummett L. Testing Hypotheses for the Maintenance of Sexual Reproduction in Campeloma limum (gastropoda Viviparidae). [Internet] [Doctoral dissertation]. University of Florida; 2008. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0023781.
Council of Science Editors:
Crummett L. Testing Hypotheses for the Maintenance of Sexual Reproduction in Campeloma limum (gastropoda Viviparidae). [Doctoral Dissertation]. University of Florida; 2008. Available from: https://ufdc.ufl.edu/UFE0023781

University of Florida
20.
Mckeon, Christian.
Diversity in a Tropical Marine Mutualism.
Degree: PhD, Zoology - Biology, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0042023
► Symbiosis has been described as the most relevant and enduring biological theme in the history of our planet . These relationships are diverse and pervasive,…
(more)
▼ Symbiosis has been described as the most relevant and enduring biological theme in the history of our planet . These relationships are diverse and pervasive, reaching every habitat and the great majority of life forms. No where are they more important in ecological function, then on coral reefs. Coral reefs are quite literally powered by symbiotic relationships- the partnership between unicellular algae and corals allows the deposition of calcium carbonate. Yet other mutualisms are also important. In this work I describe the relationship between a single genus of coral, Pocillopora, and a genus of crab, Trapezia. The mutualism focuses on the defense of the coral from environmental stressors, such as predation, sedimentation, and algal overgrowth. Yet nuances exist. As any relationship can be viewed as reciprocal exploitation, the lines between mutualism and parasitism blur upon close examination. ( en )
Advisors/Committee Members: Paulay, Gustav (committee chair), Gillooly, James (committee member), Bolker, Benjamin M. (committee member), Silliman, Brian (committee member), Bruna, Emilio M. (committee member).
Subjects/Keywords: Coral reefs; Corals; Crabs; Ecology; Mutualism; Predation; Predators; Sediments; Species; Symbionts; cnidaria, coral, crustacea, decapoda, diversity, ecology, mutualism, pocillopora, reef, symbiosis, systematic, trapezia
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mckeon, C. (2010). Diversity in a Tropical Marine Mutualism. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0042023
Chicago Manual of Style (16th Edition):
Mckeon, Christian. “Diversity in a Tropical Marine Mutualism.” 2010. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0042023.
MLA Handbook (7th Edition):
Mckeon, Christian. “Diversity in a Tropical Marine Mutualism.” 2010. Web. 16 Jan 2021.
Vancouver:
Mckeon C. Diversity in a Tropical Marine Mutualism. [Internet] [Doctoral dissertation]. University of Florida; 2010. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0042023.
Council of Science Editors:
Mckeon C. Diversity in a Tropical Marine Mutualism. [Doctoral Dissertation]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0042023

University of Florida
21.
Brando, Paulo.
Effects of Episodic Droughts and Fire on the Carbon Cycle of Amazonian Vegetation Field Research and Modeling of a Near-Term Forest Dieback.
Degree: PhD, Interdisciplinary Ecology, 2010, University of Florida
URL: https://ufdc.ufl.edu/UFE0041595
► Climate change may cause decreased rainfall in Amazonia and move forests to large-scale dieback events. To inform debates about this issue, I evaluated the impacts…
(more)
▼ Climate change may cause decreased rainfall in Amazonia and move forests to large-scale dieback events. To inform debates about this issue, I evaluated the impacts of drought and fire on Amazonian vegetation. Using a throughfall exclusion experiment, I found that wood production was the most sensitive component of above-ground net primary productivity to drought and that aboveground carbon stocks declined by 32.5 Mg ha-1 over 6 years of the treatment. These results indicate that severe droughts can substantially reduce forest C stocks in the Amazon. Based on a process-based model (CARLUC) that incorporates results from that partial throughfall exclusion experiment, I showed that total C stocks tended to increase between 1995-2004 (dry season) over the Amazon, corresponding to increases in photosynthetic active radiation. These results could partially explain the increases in biomass observed in the field over decades in the Amazon. To clarify how the gross productivity of Amazonian is influenced by drought, I used improved MODIS-enhanced vegetation index measurements (EVI) to show that in densely forested areas of the Amazon, no climatic variable tested contributed to explaining the high EVI inter-annual variability. Instead, I found evidences that suggest that production of new leaves could play an important role in the inter-annual EVI variability, but not necessarily in changes in vegetation productivity. These findings suggest that it still is unclear whether EVI can be employed as a tool to measure the vulnerability of tropical forests to drought. Finally, I studied the mechanisms associated with fire-induced tree mortality in a tropical forests in the southern Amazon. I found that the presence of water in the bark reduced the differential in temperature between the fire and vascular cambium due to boiling water in the bark. Also, I show that experimental fires influenced mortality through several processes unrelated to cambium insulation, suggesting that several plant traits that reduce the negative and indirect effects of fire should also be considered in the assessments of tropical forests' vulnerability to fire. In conclusion, I found evidence that droughts and fires exert strong influences on the terrestrial carbon cycling, but no evidences for imminent regime shifts in the region driven by climate change alone. ( en )
Advisors/Committee Members: Putz, Francis E. (committee chair), Bolker, Benjamin M. (committee member), Kobziar, Leda Nikola (committee member), Cropper, Wendell P. (committee member), Schuur, Edward A. (committee member), Nepstad, Daniel (committee member).
Subjects/Keywords: Cambium; Carbon; Climate models; Drought; Forest trees; Forests; Mortality; Trees; Tropical forests; Vegetation; amazon, bark, cambium, carbon, climate, conservation, drought, evi, fire, modis, mortality, phenology, tree, tropical
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Brando, P. (2010). Effects of Episodic Droughts and Fire on the Carbon Cycle of Amazonian Vegetation Field Research and Modeling of a Near-Term Forest Dieback. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0041595
Chicago Manual of Style (16th Edition):
Brando, Paulo. “Effects of Episodic Droughts and Fire on the Carbon Cycle of Amazonian Vegetation Field Research and Modeling of a Near-Term Forest Dieback.” 2010. Doctoral Dissertation, University of Florida. Accessed January 16, 2021.
https://ufdc.ufl.edu/UFE0041595.
MLA Handbook (7th Edition):
Brando, Paulo. “Effects of Episodic Droughts and Fire on the Carbon Cycle of Amazonian Vegetation Field Research and Modeling of a Near-Term Forest Dieback.” 2010. Web. 16 Jan 2021.
Vancouver:
Brando P. Effects of Episodic Droughts and Fire on the Carbon Cycle of Amazonian Vegetation Field Research and Modeling of a Near-Term Forest Dieback. [Internet] [Doctoral dissertation]. University of Florida; 2010. [cited 2021 Jan 16].
Available from: https://ufdc.ufl.edu/UFE0041595.
Council of Science Editors:
Brando P. Effects of Episodic Droughts and Fire on the Carbon Cycle of Amazonian Vegetation Field Research and Modeling of a Near-Term Forest Dieback. [Doctoral Dissertation]. University of Florida; 2010. Available from: https://ufdc.ufl.edu/UFE0041595
.