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yes / Shear failure of concrete elements reinforced with Fiber Reinforced Polymer (FRP) bars is generally brittle, requiring accurate predictions to avoid it. In the last decade, a variety of artificial intelligence based approaches have been successfully applied to predict the shear capacity of FRP Reinforced Concrete (FRP-RC). In this paper, a new approach, namely, biogeography-based programming (BBP) is introduced for predicting the shear capacity of FRP-RC beams based on test results available in the literature. The performance of the BBP model is compared with several shear design equations, two previously developed artificial intelligence models and experimental results. It was found that the proposed model provides the most accurate results in calculating the shear capacity of FRP-RC beams among the considered shear capacity models. The proposed BBP model can also correctly predict the trend of different influencing variables on the shear capacity of FRP-RC beams.

The deep sea is the largest ecosystem on the planet, comprising more than 90% of the volume that life can inhabit, yet it is the least explored biome in the world. The deep sea includes the benthos, which makes up 91.5 % of all the seafloor globally, and the water column deeper than 200 meters. It hosts a wealth of ecosystems including deep-sea vents, seamount coral gardens, abyssal plains, high-productivity whale falls, and life even in the deepest trenches. We now understand that all of these ecosystems host a variety of habitats, each with their own ecology and unique species. These ecosystems and habitats- and their associated biodiversity- provide essential ecosystem services such as carbon sequestration, nutrient regeneration, microbial processes detoxification, fisheries provisioning, and many others. However, despite the uniqueness of these ecosystems and the importance of the services they provide, we still know far less about them than we do about their shallow water and terrestrial counterparts. In this dissertation, I contribute new insights about the patterns of biodiversity in the Pacific Ocean across a large geographic area, and across a wide range of depths. To that end, in Chapter 1, I have used one of the largest ocean exploration datasets to look for patterns of the abundance and diversity across the most common benthic invertebrate families found on Pacific seamounts: Anthozoa, Porifera, and Echinodermata across the Central and Western Pacific. In addition to quantifying the diversity and abundance of known taxa, I also documented patterns of as-of-yet unidentified taxa by region, depth, and deepwater feature (seamount shape). Building on patterns associated with seamount shape that were described in Chapter 2, I focused on the effect of seamount shape on the diversity and abundance of deep-sea coral communities in Chapter 3. The analysis presented in Chapter 3 provides strong support for the novel hypothesis that gross seamount morphology is a significant driver of community composition. In Chapter 4, I focused on a single seamount to investigate biodiversity and abundance of coral and sponge taxa on a finer spatial scale, examining the role of direction (N, S, E, W) on different flanks of a single equatorial seamount. This analysis yielded interesting consistent patterns of zonation on all sides of the seamount in terms of depth, but with differences in abundance patterns on each flank for individual taxa. Finally, in Chapter 5, I took a global perspective to investigate gaps in deepwater data, with the goal of determining what regions need further exploration to conclusively determine patterns of deep-sea biodiversity, which will be critical for determining the health of deepwater ecosystems under climate change conditions with increased exploitation pressure and cooccuring with increased conservation efforts. Merging Ocean Biogeographic Information System (OBIS) records with the largest collection of deep submergence dive records ever collected, I used proposed biogeographic provinces schema to identify areas with the least supporting data. Additionally, I coupled records from OBIS with climate change projections to identify the areas with the fewest number of biodiversity records that are likely to change the fastest under different IPCC projections. These areas of low number of records and high likelihood of change by the end of the century should become priority targets for future exploration. Taken together, this dissertation provides valuable insights and generates new hypotheses about patterns and drivers of deep-sea biodiversity, and puts forth recommendations for future research and exploration efforts.

The status of whitebark pine (Pinus albicaulis), a foundation and keystone species and a pioneer establisher at alpine treeline, is threatened by the invasive and exotic fungal pathogen (Cronartium ribicola) that causes white pine blister rust in five-needled pines. Originally thought to be limited to moderate environments, the disease is now found extensively throughout colder and dryer regions east of the Continental Divide, including alpine treeline. My research objective was to determine how blister rust infection of treeline whitebark pine varies across Glacier National Park. I present findings from field sampling conducted in July 2008 in Glacier National Park, Montana. Thirty plots were randomly placed at 6 different treeline study sites on the eastern slopes of the Continental Divide. Vegetative and geomorphic characteristics, along with presence/absence and level of blister rust intensity, were detailed within each plot. Vegetation measurements included conifer composition, tree island dimensions and windward growth patterns, evidence and intensity of blister rust, as well as shelter type. Field-measured topographic characteristics included elevation, aspect, and slope. In addition, high resolution GPS-derived DEMs were created at each plot in order to model the land surface and calculate detailed environmental variables in a GIS. Environmental and blister rust intensity variables were used to determine spatial correlates of blister rust infection at treeline. The resulting blister rust prediction model (P < 0.001, F(4,25) = 6.79, R2 = 0.52, Adjusted R2 = 0.44) suggests that areas exhibiting increased wind speed, northwest facing slopes, high flow accumulation rates, and close proximity to perennial streams have a higher likelihood of blister rust intensity, specifically total canker density. Results of this research may contribute to the understanding of the dynamics of this disease, and prove useful in whitebark ecosystem management and conservation. / Master of Science

Microbial community composition plays a vital role in soil biogeochemical cycling. Information that explains the biogeography of microorganisms is consequently necessary for predicting the timing and magnitude of important ecosystem services mediated by soil biota, such as decomposition and nutrient cycling. Theory developed to explain patterns in plant and animal distributions such as the prevalent relationship between ecosystem productivity and diversity may be successfully extended to microbial systems and accelerate an emerging ecological understanding of the "unseen majority." These considerations suggest a need to define the important mechanisms which affect microbial biogeography as well as the sensitivity of community structure/function to changing climatic or environmental conditions. To this end, my dissertation covers three data chapters in which I have 1) examined patterns in bacterial biogeography using gradients of environmental severity and productivity to identify changes in community diversity (e.g. taxonomic richness) and structure (e.g. similarity); 2) detected potential bacterial ecotypes associated with distinct soil habitats such as those of high alkalinity or electrical conductivity and; 3) measured environmental controls over the function (e.g. primary production, exoenzyme activity) of soil organisms in an environment of severe environmental limitations. Sampling was performed in the polar desert of Antarctica's McMurdo Dry Valleys, a model ecosystem which hosts microbially-dominated soil foodwebs and displays heterogeneously distributed soil properties across the landscape. Results for Chapter 2 indicate differential effects of resource availability and geochemical severity on bacterial communities, with a significant productivity-diversity relationship that plateaus near the highest observed concentrations of the limiting resource organic carbon (0.30mg C/g soil). Geochemical severity (e.g. pH, electrical conductivity) primarily affected bacterial community similarity and successfully explained the divergent structure of a subset of samples. 16S rRNA amplicon pyrosequencing further revealed in Chapter 3 the identity of specific phyla that preferentially exist within certain habitats (i.e. Acidobacteria in alkaline soils, Nitrospira in mesic soils) suggesting the presence of niche specialists and spatial heterogeneity of taxa-specific functions (i.e. nitrite oxidation). Additionally, environmental parameters had different explanatory power towards predicting bacterial richness at varying taxonomic scales, from 57% of phylum-level richness with pH to 91% of order- and genus-level richness with moisture. Finally, Chapter 4 details a simultaneous sampling of soil communities and their associated ecosystem functions (primary productivity, enzymatic decomposition) and indicates that the overall organic substrate diversity may be greater in mesic soils where bacterial diversity is also highest, thus a potentially unforeseen driver of community dynamics. I also quantified annual rates of soil production which range between 0.7 - 18.1g C/m2/yr from the more arid to productive soils, respectively. In conclusion, the extension of biogeographical theory for macroorganisms has proven successful and both environmental severity and resource availability have obvious (although different) effects on the diversity and composition of soil microbial communities. / Ph. D.

Mountain pine beetles (Dendroctonus ponderosae) are native insects that have decimated millions of hectares of mature pine (Pinaceae) forests in western North America. The purpose of this study is to investigate biophysical and climatic correlates of Mountain Pine Beetle (MPB) insect outbreaks in the Crown of the Continent Ecosystem (CCE) from 1962 to 2014 using Aerial Detection Survey (ADS) and climate data. Specific objectives were: 1) to develop statistical models to determine how selected biophysical correlates (slope, aspect, elevation, and latitude) and 2) to understand how local and global climate variables relate to the extent of the MPB infestations in the CCE, and 3) to contextualize the results of the models with historical climate data. Overall, the major findings of this study are: 1) despite its limitations, the ADS data seems suitable for analysis of beetle damage with respect to climate and topographic factors, on a regional scale, 2) there appears to be a link between local biophysical factors and winter precipitation and TPA within the CCE, and 3) a combination of a negative-phase PDO and La Niña is important in forecasting a decline in MPB spread, during a given year. This study is the first, to our knowledge, to explore spatio-temporal patterns of MPB outbreaks using biophysical factors, and both local and global climate variables, over a fifty-year timespan in the CCE. In the future, additional geospatial analyses may enable a landscape assessment of factors contributing to variability of MPB infestation and damage as this insect continues to spread. / Master of Science / Mountain pine beetles (Dendroctonus ponderosae) are a native insect that has decimated millions of hectares of mature pine forests in western North America. The purpose of this study was to investigate, using GIS-derived variables, biophysical and climatic factors that have influenced past mountain pine beetle insect outbreaks, as evident by beetle-induced tree mortality in the Crown of the Continent Ecosystem (CCE) from 1962 to 2014. Specific objectives of this study were to determine how selected biophysical variables (slope, aspect, elevation, and latitude), regional climate variables (temperature, precipitation, and drought) and global climate oscillations (ENSO, PDO, NAO, AO, and PNA) relate to bark beetle infestations in the Crown of the Continent Ecosystem from 1962 through 2014, as measured by aerial surveyrecorded tree mortality. We sought to contextualize the results of the statistical models with historical data to further understand the relationship between increases and decreases of tree mortality by comparing these trends to geopotential height and sea-surface temperatures that may influence CCE climate. Our work revealed first, that while the aerial survey data has important limitations, overall it is a useful dataset for analyzing historical spatio-temporal patterns of insect infestations. Second, there appears to be a link between local biophysical factors, such as latitude, elevation, and winter precipitation (as opposed to global climate factors) and tree mortality within the CCE. Local climate analysis revealed the importance of winter precipitation to be the biggest influence of MPB decrease or increase along with lower geopotential heights during a decline in MPB spread over the CCE. Finally, a combination of a negative PDO and El Niño was important in forecasting a decline in MPB spread, as shown by damage, during a given year. This is the first study to use aerial survey data in a geospatial analysis incorporating biophysical variables for the US portion of the Crown of the Continent Ecosystem. Additionally, this study is unique to explore the potential relationship between global teleconnections and regional climate in the CCE area, and the spatio-temporal extent of mountain pine beetle infestations.

The subsidized island biogeography hypothesis proposes that nutrient subsidies, those translocated from one ecosystem to another, can indirectly influence species richness on islands by directly increasing terrestrial productivity. However, the lack of a formal statistical model makes it difficult to assess the strength of the hypothesis. I created a formal subsidized island biogeography model to determine how nutrient subsidies, in addition to area and distance from mainland, influence tree species richness. My model showed that an increase in terrestrial nitrogen abundance results in a decrease of tree species richness. Soil and plant δ 15N values were higher than expected and it is likely that nutrient subsidies from the marine environment are responsible for 15N enrichment. However, the range of observed nitrogen abundance is similar to inland coastal-zone forests, indicating that islands are similarly nitrogen deprived and may not be receiving enough nutrient subsidies to alter productivity. Tree species decline may therefore be more strongly related to the environmental conditions leading to patterns of nitrogen abundance rather than the abundance of nitrogen itself. Additionally, I proposed that bald eagles (Haliaeetus leucocephalus) are vectors of nutrient subsidies, depositing nutrient-rich guano at nest sites, which could alter soil chemistry and vegetation composition. In an exploratory study of seven nest sites, I found higher soil phosphorous at eagle nest sites relative to control sites (~ 33% higher). Phosphorous is a limiting nutrient in coastal temperate forests, additions help to alleviate chlorosis and slow growth especially when paired with nitrogen. Higher potassium concentration also occurred on eagle-inhabited islands but was not associated specifically with current nest sites, perhaps reflecting differential persistence of macronutrients in the soil. Despite expectations, soil δ 15N abundance was not statistically higher at eagle nest sites. Total soil nitrogen was also not statistically higher at eagle nest sites. There were no significant differences between vegetation composition at eagle nest sites and reference sites, but reference sites tended to be dominated by shrub species. Additionally, I proposed that bald eagles (Haliaeetus leucocephalus) are vectors of nutrient subsidies, depositing nutrient-rich guano at nest sites, which could alter soil chemistry and vegetation composition. In an exploratory study of seven nest sites, I found higher soil phosphorous at eagle nest sites relative to control sites (~ 33% higher). Phosphorous is a limiting nutrient in coastal temperate forests, additions help to alleviate chlorosis and slow growth especially when paired with nitrogen. Higher potassium concentration also occurred on eagle-inhabited islands but was not associated specifically with current nest sites, perhaps reflecting differential persistence of macronutrients in the soil. I expected to observe elevated nitrogen isotope signatures (δ 15N) given bald eagles’ position in the trophic web and the potential for volatilization of guano but soil δ 15N abundance was not statistically higher at eagle nest sites. Total soil nitrogen was also not statistically higher at eagle nest sites. There were no significant differences between vegetation composition at eagle nest sites and reference sites, but reference sites tended to be dominated by shrub species / Graduate

Geography and Geology / Master / Master of Philosophy

Orientador: Prof. Dr. Charles Morphy D. dos Santos / Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Evolução e Diversidade, 2017. / O conhecimento da história da vida na Terra é fundamental para entender a atual distribuição dos organismos e para prevê-la no futuro. O estabelecimento de áreas de endemismo e a análise da estruturação filogenética dessas áreas são os primeiros passos para que se possa compreender a história evolutiva e as interações ecológicas entre organismo-espaço e organismo-organismo, a fim de fornecer subsídios para ações conservacionistas. A infraordem Tabanomorpha (Diptera, Brachycera), um grupo antigo, de distribuição global e pouca resolução biogeográfica, é um bom modelo de estudo para discutir a relação entre biodiversidade, padrões filogenéticos e conservação. Os objetivos desta tese foram: i) estudar aspectos biogeográficos dos grupos de Tabanomorpha, em particular identificar áreas de endemismo neotropicais e globais, e ii) estudar o índice de diversidade filogenética de Faith. Para isso, um banco de dados com registros de ocorrência de ~5.000 espécies de Tabanomorpha foi compilado. As áreas de endemismo foram delimitadas a partir de uma análise de endemicidade, utilizando o programa NDM/VNDM. Na região Neotropical, 13 áreas de endemismo foram identificadas, compreendendo cinco componentes: Norte da América do Sul (NSA), Sudeste da América do Sul (SESA), América Central (CA), Savana Brasileira (BS), Andes Central (CAn). De modo geral, estes componentes são congruentes com as propostas de regionalização mais recentes para a região Neotropical. Na análise global, 18 áreas de endemismo foram identificadas: seis áreas na região Neártica, duas na região Paleártica, as regiões Oriental, Australiana e Africana tiveram três áreas cada, e a região Neotropical apareceu como uma área única. Essas áreas foram comparadas com estudos realizados para diversos táxons, apresentando congruências e evidenciando a possibilidade de utilização dos insetos na determinação de padrões globais de endemismo. A partir dos resultados de ambas as análises de endemicidade, a família Rhagionidae foi utilizada como modelo para sugestão de um protocolo de análise de biogeografia histórica, utilizando três distintos de biogeografia cladística: (1) um método baseado em padrão (BPA), um método baseado em eventos (DIVA) e um método baseado em barreiras (SAV). O método baseado em padrão descreve o padrão geral das relações das áreas, com possíveis áreas problemáticas a serem explicadas pelo método baseado em eventos (sob interpretação de diferentes processos: vicariância, dispersão, duplicação, extinção). O método baseado em barreiras testa a história biogeográfica estabelecida pelos métodos anteriores, apontando possíveis barreiras. Essas informações biogeográficas mais amplas facilitam a incorporação subsequente da história evolutiva nas análises de diversidade. Por fim, foi realizada uma análise de diversidade filogenética da família Tabanidae nas áreas de endemismo identificadas na região Neotropical, baseada no Índice de Diversidade Filogenética de Faith. O resultado mostrou que a distribuição geral dos gêneros de tabanídeos é agrupada filogeneticamente, ou seja, constituída por gêneros estreitamente relacionados. A presente tese configura o início de um inventário de dípteros tabanomorfos em áreas neotropicais potencialmente favorável aos estudos de biogeografia da conservação por tratar explicitamente da determinação de áreas de endemismo Neotropicais baseadas na distribuição de Tabanomorpha, e avaliadas em sua diversidade filogenética em Tabanidae, a família mais abrangente da infraordem. / The knowledge of the history of life on Earth is fundamental to understand the current distribution of organisms and to predict it in the future. The establishment of areas of endemism and the analysis of the phylogenetic structure of these areas are the first steps in understanding the evolutionary history and the ecological interactions between organismspace and organism-organism, in order to provide subsidies for conservation actions. The infraorder Tabanomorpha (Diptera, Brachycera), an ancient group with a global distribution and low biogeographic resolution, is a good study model to discuss the relationship between biodiversity, phylogenetic patterns and conservation. The objectives of this PhD thesis were: i) to study biogeographical aspects of groups of Tabanomorpha, particularly identifying Neotropical and global areas of endemism, and ii) to study Faith's phylogenetic diversity index. For this purpose, a database with occurrence records of ~ 5,000 species of Tabanomorpha was compiled. The areas of endemism were delimited from an endemicity analysis of this database, using the NDM/VNDM program. In the Neotropical region, 13 areas of endemism were identified for the Neotropical region, comprising five components: Northern South America (NSA), Southeastern South America (SESA), Central America(CA), Brazilian Savannah (BS), and Central Andes (CAn). In general, those components are congruent with the most recent bioregionalization proposals of Neotropical region. In the global analysis, 18 areas of endemism were identified: six areas in Neartic region, two areas in Palearctic region, Oriental, Australian and African regions presented three areas each, and Neotropical region appeared as a single area. Those areas were compared with global studies carried out for several taxa, presenting congruencies and showing the possibility of using insects in the determination of global patterns of endemism. From the results of both analyzesof endemicity, the family Rhagionidae was used as a model to suggest a protocol for historical biogeography analyses using three distinct methods of cladistic biogeography: (1) a pattern based method (BPA), an event-based method (DIVA) and a barrier-based method (SAV). The pattern-based method depicts the general pattern of area relationships, with possible problematic areas to be explained by the event-based method (under interpretation of different processes: vicariance, dispersion, duplication, extinction). The barrier-based method tests the biogeographical history established by the previous methods, revealing possible barriers. This broader biogeographical information facilitates the subsequent incorporation of evolutionary history into diversity analyses. Finally, an analysis of the phylogenetic diversity of the family Tabanidae was carried out in the areas of endemism identified in the Neotropical region, based on Faith¿s Phylogenetic Divers ty index. The result of the analysis showed that the general distribution of the tabanid genera in the five main areas of endemism in theNeotropical region is phylogenetically clustered, that is, composed of closely related genera. The present thesis is the beginning of an inventory of dipterans of infraorder Tabanomorpha in Neotropical areas, potentially favorable to conservation biogeography studies by explicitly determining Neotropical areas of endemism based on the Tabanomorpha distribution, and evaluating their phylogenetic diversity in Tabanidae, the major family of the infraorder.