O arroz (Oryza sativa L.) integral é rico em compostos fenólicos livres e conjugados (solúveis) e ligados (insolúveis). Atribui-se a estas substâncias propriedades benéficas à saúde humana devido à elevada ação antioxidante. Porém, pouco se conhece sobre o efeito do ambiente e de processos tecnológicos como a parboilização sobre os seus teores. Este trabalho teve como objetivo estudar a variabilidade nos teores de compostos fenólicos solúveis e insolúveis em arroz integral em função da região de plantio e safras. Avaliou-se também o efeito da parboilização nos fenólicos e sua atividade antioxidante. Fez parte do escopo desta pesquisa analisar a composição química de 9 amostras de arroz integral e compará-la ao arroz parboilizado integral, e com isso contribuir com dados para tabelas de composição de alimentos. Foram analisadas 54 amostras de arroz integral fornecidas pela Epagri/Estação Experimental de Itajaí, pertencentes a três cultivares comerciais, produzidas simultaneamente em três regiões do Estado de Santa Catarina por diferentes produtores em sistema irrigado e colhidas nas safras de 2007/2008 e 2008/2009. Todas as amostras referentes à safra 2007/2008 foram analisadas antes e após a parboilização. Os compostos fenólicos solúveis foram extraídos com EtOH 80% e os insolúveis com acetato de etila após tratamento em meio alcalino. O método espectrofotométrico de Folin-Ciocalteau foi empregado para a sua quantificação e os métodos ORAC (Oxygen radical absorbance capacity) e DPPH (1,1-difenil-2-picril-hidrazil) para avaliar a atividade antioxidante. O teor médio de compostos fenólicos totais no arroz integral foi da ordem de 1300 mg eq. ácido ferúlico/kg, sendo que a proporção de fenólicos solúveis e insolúveis foi de 55:45. As safras demonstraram ter maior influência nos teores de fenólicos do que as regiões de plantio. A parboilização ocasionou uma perda média de 32% dos compostos fenólicos totais, sendo a fração solúvel a mais afetada pelo processo. O teor médio de fenólicos insolúveis nas 27 amostras não sofreu alteração pela parboilização, apesar de variações individuais. Os métodos de DPPH e ORAC foram igualmente adequados para avaliar a atividade antioxidante dos extratos de arroz, antes e após a parboilização. No arroz não parboilizado a atividade antioxidante se deve majoritariamente aos fenólicos solúveis, enquanto no arroz parboilizado, as duas frações, solúvel como insolúvel, contribuíram quase equitativamente com a capacidade antioxidante. Os compostos fenólicos apresentaram forte correlação com a atividade antioxidante pelas metodologias de DPPH e ORAC. O arroz integral e o arroz parboilizado integral apresentaram similaridade em relação à composição química. / Brown rice (Oryza sativa L.) is rich in phenolic compounds which, from an analytical point of view, may be found in free, conjugated (soluble) and bound (insoluble) forms. These substances are known for their potential benefits in the prevention of oxidative stress-related diseases. However, the effects of technological processes, such as parboiling, on these compounds and their antioxidant capacity are yet unknown. The objective of this study was to evaluate the variability of phenolic compounds and their fractions (soluble and insoluble), as well as their antioxidant activity, in three economically attractive rice cultivars from different planting regions and harvest periods. Furthermore, the effect on these substances by the parboiling process of brown rice was also investigated. In addition, the chemical composition of nine samples of brown rice and parboiled brown rice were determined in order to contribute to food composition data tables. Fifty four brown rice samples of three commercial cultivars, provided by Epagri/Itajaí Experimental Station, were cultivated simultaneously with irrigation system by different producers in three regions of Santa Catarina and harvested in 2007/2008 and 2008/2009. Twenty seven samples, from the first harvest, were analyzed before and after parboiling. Soluble phenolic compounds were extracted with EtOH 80% and bound phenolics were released by NaOH, then extracted with ethyl acetate. The Folin-Ciocalteu spectrophotometric method was applied to quantify phenolic compounds, while antioxidant activity was measured by the oxygen radical absorbance capacity (ORAC) assay and by the 1,1- diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging method. The average content of total phenolic compounds in non-parboiled brown rice was approximately 1300 mg eq. ferulic acid/kg, while the ratio between soluble and insoluble fractions was 55:45. The period of harvest had greater influence on the phenolic contents than cultivation area. The parboiling process decreased on about 32% the mean soluble phenolic content, while insoluble compounds were not affected, despite individual variations with gains and losses. Both, the ORAC and DPPH methods used to evaluate antioxidant activity, were equally suitable to assess parboiled and non-parboiled rice extracts. In non-parboiled rice antioxidant capacity was mainly due to soluble phenolics, while in parboiled rice both soluble and insoluble fractions contributed almost equally. Correlation coefficients between soluble phenolics and antioxidant activity were high for both DPPH and ORAC methods. Moreover, chemical composition was similar between parboiled and non-parboiled brown rice.

Tendo em vista a natureza finita dos minerais naturais, torna-se evidente a necessidade de utilizarmos este recurso de maneira estratégica. Desta forma, diversas pesquisas vêm sendo desenvolvidas principalmente nas áreas químicas, metalúrgicas e mineralógicas desde as etapas de extração, beneficiamento, aplicação e reutilização dos resíduos de minérios. Portanto, é extremamente importante a intensificação dos estudos para aumentar o conhecimento quanto às características e propriedades físico-químicas destes minerais, visando melhorar o seu aproveitamento e longevidade das jazidas naturais, como as fontes de bauxita, que é a principal matéria-prima para a produção de óxido de alumínio fundido. Na sua forma cristalina mais comum, denominada coríndon, ou óxido de alumínio ?, sua baixa condutividade elétrica, baixo calor específico, alta condutividade térmica, alto ponto de fusão, elevada dureza e resistência mecânica, o torna adequado para uso em produtos refratários, cerâmicos e abrasivos tais como, lixas, rebolos, ferramentas de corte e de polimento. Na síntese deste produto as principais impurezas que afetam a qualidade dos grãos são Fe, Si, Ca, K, Na e Zr, oriundas da matéria prima bauxita e da carta de mistura, composta por ilmenita, limalha de ferro, carvão vegetal e coque de petróleo. Desta forma, o presente trabalho assumiu o objetivo de estudar a dispersão das propriedades físico-químicas em blocos de alumina fundida marrom obtida em fornos Higgins a arco por eletrofusão, produzidos na Saint-Gobain Abrasivos, unidade de Lorena, SP. Por fim, foram utilizadas técnicas de caracterização físico-químicas de difratometria de raios X (DRX), análises químicas de fluorescência de raios X (FRX), ensaio de dureza Knoop e caracterização microestrutural via (MEV/EDS). Desta forma, foi definido o mapeamento composicional nos blocos de alumina eletrofundida marrom, que servirão como referência técnico-científica para subsidiar ações de melhoria deste produto, em decorrência do avanço do estado da arte deste referido assunto. / The mineral ores are not renewable sources and we need to use it in the best way possible. In this way, a large number of researches are being developed around the world aiming the improvement of current methods of production mainly in chemical, metallurgy, mineralogical from the steps of extraction, processing, application and reuse of waste ore. Therefore, it is extremely important to intensify the studies to increase the knowledge about the characteristics and physicochemical properties of these minerals, in order to improve their utilization and longevity of natural deposits, such as sources of bauxite, which is the main raw material to product aluminum oxide fused. In its most common crystalline form, called corundum or ?-aluminum oxide, its low electrical conductivity, low specific heat, high thermal conductivity, high melting point, high hardness and mechanical strength, making it suitable for use as refractories, ceramics and fine or coarse abrasives. The synthesis of this product major impurities that affect quality of grain is Fe, Si, Ca, K, Na and Zr, derived from the raw material bauxite and the mixture chart consisting of ilmenite, iron filings, charcoal and coke oil. Thus, this shows the dispersion of physicochemical properties of brown fused alumina blocks produced by eletrocfusion at Higgins furnace process in the company Saint Gobain Abrasivos, Lorena- SP. Finally, the samples were physicochemical analyzed by X ray diffraction (XRD), chemical analyses by X ray fluorescence (XRF), hardnes using Knoop method, microstructural characterization by (SEM). The results of this work show a compositional gradient map of the fused alumina block; that shows the main physicochemical differences into the block, to support changes in the alumina production process; and it is also important to improve the actual state of art of this particular theme.

Submitted by Leticia Schettini (leticia@ufrrj.br) on 2016-10-11T13:42:58Z No. of bitstreams: 1 2005 - Carmem L?cia Fernandes Medeiros.pdf: 467565 bytes, checksum: ad65a23289538d4ef20044cdf3dd5a32 (MD5) / Made available in DSpace on 2016-10-11T13:42:58Z (GMT). No. of bitstreams: 1 2005 - Carmem L?cia Fernandes Medeiros.pdf: 467565 bytes, checksum: ad65a23289538d4ef20044cdf3dd5a32 (MD5) Previous issue date: 2005-12-16 / Between July and August of 2005 nine brown brocket deer (Mazama gouazoubira), were housed in individual stalls, and submitted to three treatment containing three repetitions, with the objective of evaluating the consumption and the digestibility of alfalfa (Medicago sativa), mulberry leaves (Morus Alba) and perennial soybean (Neonotonia Wightii), as well as the ingestive behavior of the animals in relation to the diets the one that was submitted, being monitored for 24 hours, in regular intervals of five minutes, being determined the feeding activities, rumination, water consumption, leisure and other activities. There was significant difference (P < 0,05) in the natural matter consumption; however, when an adjustment for dry matter, the difference did not persist. It was observed differentiates (P < 0,05) in the times of ingestion, rumination, leisure and other activities. The animals that consumed mulberry leaves spent more time ingesting, ruminating and in leisure than the animals that consumed the other foods and for that they spent less time with other activities. There was not influence (P > 0,05) of the food type on the tax of mastication of the animals. There was significant difference (P < 0,01) in the coefficients of digestibility of the dry matter and of the fractions of the fiber (P < 0,05). Was ended that the consumption of matter drought did not differ among the treatments, although the animals that consumed mulberry leaves have spent more time in the ingestion and rumination of that food, suggesting possible inherent differences to the cellular wall of this bulky one interfering in these varied. The brown brocket deer used in this study, they were shown relatively efficient in the digestion of the fiber, when this was used as partial ingredient of the diet, and the animals that consumed mulberry leaves and perennial soybean, obtained the largest digestibility coefficients. / Entre Julho e Agosto de 2005 nove veados-catingueiro (Mazama gouazoubira), foram alojados em baias individuais, distribu?dos em um delineamento experimental inteiramente casualizado, com tr?s tratamentos e tr?s repeti??es, com o objetivo de avaliar o consumo e a digestibilidade de tr?s alimentos: alfafa (Medicago sativa), folhas de amoreira (Morus Alba) e soja perene (Neonotonia Wightii), bem como o comportamento ingestivo dos animais em rela??o ?s dietas a que foram submetidos, sendo monitorados durante 24 horas, em intervalos regulares de cinco minutos, determinando-se as atividades de alimenta??o, rumina??o, consumo de ?gua, ?cio e outras atividades. Houve diferen?a significativa (P < 0,05) no consumo de mat?ria natural, entretanto, quando se efetuou um ajuste para mat?ria seca dos alimentos, a diferen?a n?o persistiu. Observou-se diferen?a (P < 0,05) nos tempos de ingest?o, rumina??o, ?cio e outras atividades. Os animais que consumiram folhas de amoreira, gastaram mais tempo ingerindo, ruminando e em ?cio do que os animais que consumiram os outros alimentos e por isso gastaram menos tempo com outras atividades. N?o houve influ?ncia (P > 0,05) do tipo de alimento sobre a taxa de mastiga??o dos animais. Houve diferen?a significativa (P < 0,01) nos coeficientes de digestibilidade da mat?ria seca e das fra??es da fibra (P < 0,05). Concluiu-se que o consumo de mat?ria seca n?o diferiu entre os tratamentos, embora os animais que consumiram folhas de amoreira tenham gastado mais tempo na ingest?o e rumina??o desse alimento, sugerindo poss?veis diferen?as inerentes ? parede celular deste volumoso interferindo nestas vari?veis. Os veados-catingueiros utilizados neste estudo, mostraram-se relativamente eficientes na digest?o da fibra, quando esta foi utilizada como ingrediente parcial da dieta, sendo que os animais que consumiram folhas de amoreira e soja perene, obtiveram os maiores coeficientes de digestibilidade.

A great deal of attention has been paid to brown carbon aerosol in the troposphere because it can both scatter and absorb solar radiation, thus affecting the Earth’s climate. However, knowledge of the optical and chemical properties of brown carbon aerosol is still limited. In this thesis, we have investigated different aspects of the optical and physicochemical properties of various brown carbon aerosol samples of potential atmospheric importance. First, reactions involving the di-carbonyl species methylglyoxal (MG) have been previously suggested as an important pathway for the production of secondary organic aerosol (SOA) in the atmosphere. Reaction in an aqueous inorganic salt solution, such as ammonium sulfate (AS), leads to the formation of light-absorbing brown carbon (BrC) product. In this thesis work, we employed a variety of experimental approaches to investigate the optical and physicochemical properties of BrC aerosol generated from this AS-MG reaction (BrC (AS/MG)). Optical properties of the dried BrC (AS/MG) aerosol particles were studied by Fourier transform infrared (FTIR) extinction spectroscopy in the mid-infrared region, cavity ring-down spectroscopy (CRDS) at 403 nm in the visible, and by measuring the light scattering phase function and polarization profiles at two different visible wavelengths, 532 and 402 nm. In addition, we used UV−vis spectroscopy to measure the mass absorption coefficient (MAC) of the solution-phase reaction products. The different optical properties were measured as a function of reaction time for a period of up to 22 days. The UV-vis absorption spectra showed a clear increase in measured MAC in the visible and near UV as the solution aged. However, analysis of the light scattering data showed no significant differences between AS and BrC aerosol in the derived refractive indices at either 532 or 402 nm, even for the longest reaction times. The FTIR extinction spectra was modeled in a Mie theory simulation to derive the complex refractive index in the mid-IR range (7000-800 cm−1); the results showed no significant changes in either the real or the imaginary parts of the refractive indices for BrC (AS/MG) aerosol particles when compared to unreacted AS aerosol. From the CRDS extinction data, the optical constants for BrC (AS/MG) particles at 403 nm were also determined through a Mie theory based analysis. The retrieved real index of refraction at 403 nm is n = 1.551 ± 0.005, with an imaginary index value of k = 0.000 ± 0.002; these values do not appear to change significantly with aging time over the course of 22 days and are not markedly different from the AS aerosol values. The small imaginary index value suggests that BrC (AS/MG) aerosol formed from this pathway may not significantly contribute to warming. In addition, CRDS measurements of the BrC (AS/MG) aerosol extinction at 403 nm as a function of particle size show a significant deviation from Mie theory simulations for particles with diameters of ≳500 nm, probably as a result of non-spherical particle shape effects. We also employed atomic force microscopy (AFM)-based IR spectroscopy to investigate the morphology and chemical composition of single SOA particles. AFM analysis of the particle morphology shows that a significant fraction of BrC (AS/MG) particles with diameters of ≳500 nm are non-spherical in shape, consistent with our observed breakdown in the applicability of Mie theory for larger particles. In addition to these measurements, we have characterized additional physicochemical properties of the BrC (AS/MG) aerosol particles including hygroscopic growth using a tandem-differential mobility analyzer. Compared to AS, BrC aerosol particles are found to have lower deliquescence relative humidity (DRH), efflorescence relative humidity (ERH), and hygroscopic growth at the same relative humidity values. Second, we investigated the optical properties of the water soluble products of limonene BrC generated from ozonolysis of d-limonene with further aging by AS. Optical constants for the dried limonene BrC aerosol product were measured at 403 nm by CRDS over the course of 9 days of aging. While the fresh limonene BrC aerosol showed a significant non-zero absorption index, the aged samples showed absorption index values consistent with zero. This result was somewhat unexpected because UV-vis absorption spectra of the bulk reaction solution showed a continued increase in absorption as the solution aged. One possible explanation for this result is that there could be an increase in the fraction of volatile chromophores as the solution ages, that are then removed in the aerosol drying process. Third, we investigated optical properties and chemical compositions of several humic substance (HS) reference samples including humic acid (HA) and fulvic acid (FA) standards by CRDS, UV-vis spectroscopy, elemental analysis, and 13C NMR spectroscopy. Measurements of the optical properties of HS is important in atmospheric science, because it is thought that HS samples have similar optical properties to organic materials, such as HUmic-Like Substances (HULIS), that exist in clouds, fogs, rainwater, and atmospheric aerosol. The humic acid aerosol samples generally showed higher absorption index values than the fulvic acid aerosol samples. We also found a correlation between the absorption index and chemical composition, with the value for k generally increasing with both increasing carbon-to-oxygen atomic ratio and sample aromaticity. In addition, we compared our measured optical constants for the HS aerosol samples with results from previous studies of field collected HULIS. The absorption index values for the fulvic acid aerosol samples give a better match than the humic acid samples when compared to the results from the field collected samples. Overall, these studies provide new details of the optical and physicochemical properties of a class of brown carbon organic aerosol which may have important implications for atmospheric chemistry and climate.

Thermogenic brown and beige adipocytes convert chemical energy to heat by metabolizing glucose and lipids via uncoupling protein 1 (Ucp1), a process known as non-shivering thermogenesis. Serotonin (5-HT) neurons in the ventral medulla are known to regulate sympathetic efferent neurons in the intermediolateral nucleus (IML) necessary to maintain brown adipose tissue (BAT) activity. Previous studies show that mice lacking central 5-HT neurons are incapable of maintaining body temperature in cold, ambient conditions. Due to this direct linkage between 5-HT and thermoregulation, we hypothesized that central 5-HT neurons may be vital to the regulation of brown and beige adipocyte activity. Given that BAT consumes large amounts of substrate when active, we also hypothesized that inactivation of BAT due to deletion of the regulatory neural circuitry (5-HT neurons) would cause metabolic dysregulation. To test this, we generated mice in which the human diphtheria toxin (DT) receptor was selectively expressed in central 5-HT neurons under control of a Pet-1 promoter. Pet-1 is a transcription factor selectively located in mature, central 5-HT neurons. Coincidentally, some cells within pancreatic islets also express Pet-1, and contain adequate machinery to produce, release, and uptake 5-HT. Systemic treatment with DT eliminated 5-HT neurons and caused loss of thermoregulation, BAT steatosis, and a >50% decrease in Ucp1 expression in BAT and beige fat, indicative of reduced thermal production. In parallel, blood glucose increased 3.5-fold, free fatty acids 13.4-fold and triglycerides 6.5-fold. Intracerebroventricular (ICV) treatment with 1/30th the systemic dose of DT induced an even greater thermoregulatory impairment. The metabolic deficits following systemic DT treatment indicate that central 5-HT neurons are essential for proper metabolic regulation. However, such high levels of glucose and lipids also indicate failure of the pancreatic endocrine program following systemic treatment, likely due to moderate destruction of β-cells expressing Pet-1 and the DT receptor. Because ICV treatment caused even greater thermoregulatory and metabolic deficits, where little, if any, of the toxin would spread systemically, central 5-HT neurons are clearly essential for normal central regulation of metabolism. Interestingly, similar BAT and beige fat defects occurred in Lmx1bf/f/p mice, in which 5-HT neurons fail to develop in utero. Assessment of systemically treated animals using a euglycemic/hyperinsulinemic clamp showed extensive fasting hyperglycemia and systemic insulin resistance, coinciding with reduced glucose uptake in skeletal muscle and BAT. The hyperinsulinemic clamp failed to suppress hepatic glucose and fatty acid production, leading to the conclusion that loss of central 5-HT neurons disrupts central hepatic regulation. In attempts to induce BAT thermogenesis and metabolism, we optogenetically stimulated 5-HT neurons in the rostral raphe pallidus and measured BAT and body temperature along with blood glucose. Unfortunately, these stimulations were incapable of increasing BAT temperature and lowering blood glucose, perhaps limiting therapeutic potential of these 5-HT neurons. We conclude that 5-HT neurons are major players in central regulation of metabolic homeostasis, in part through recruitment and activation of brown and beige adipocytes and hepatic substrate production. Data also suggest that 5-HT neurons regulate glucose homeostasis via undefined neural mechanisms independently of BAT activity and pancreatic insulin secretion. Cumulative data on central 5-HT neurons indicate they are master regulators of whole-body metabolism.

Comprehensive population studies in the field of fisheries are in great demand. Many of our fishable waters are being changed, and we need to be able to predict the results of these habitat alterations. We must know how to include beneficial modifications in readjustments of habitat in order to create a fishery or prevent destruction of an existing one. The acceptable situations for good fish production in large mountain streams are not well-knowno A fishery can be properly managed only if the manager has sufficient knowledge of the carrying capacity of the habitat, the survival and mortality of the population, and the movements of the fish within the population. My study is an attempt to answer some of these questions about the self-sustaining populations of brown trout (Salmo trutta fario Linnaeus) and mountain whitefish (Prosopium williamsoni Girard) in a 5-mile section of Logan River, Utah.

The social behavior of brown bears (Ursus arctos) was studied during the summers of 1972 and 1973 as bears fished for salmon at McNeil River, Alaska. Study objectives were to determine behavioral characteristics of bears in relation to sex and age, changes in social behavior over a 40-day long fishing season, social and environmental parameters correlated with the occurrence of behavior, and to test the hypothesis that brown bears modify social behavior in a feeding aggregation to exploit a resource limited in time and space. Over one-half of the agonistic interactions consisted of passive deferrals. Encounters that included elements of overt threat were jawing, sparring, charges, and fighting. Jawing was the most prevalent agonistic encounter and generally occurred between individuals of the same sex and age class. Sparring, charges and fights were generally initiated by larger bears against smaller individuals. Females with young were most intolerant. Adult males participated in few encounters that involved overt threat since most bears avoided them. Single adult and adolescent females were neither particularly aggressive nor especially tolerant. Adolescent males adjusted quickly to McNeil Falls and as a group were unaggressive. Subadults were wary and frequently were the objects of aggression of older bears. Social dominance relationships between bears of the same class were often ambiguous, the exception being adult males. Relationships between bears of different classes were mostly stable; adult males were dominant, followed in order by females with young, single adult females, adolescents, and subadults. However, apparent reversals also were common between single adult females and adolescent males. Nonagonistic encounters occurred only when salmon were exceptionally abundant and usually involved adolescent and subadult bears. Behavioral changes over time included a decline in the frequency of running deferrals, a decline in deferrals in total, and a decline in the frequency of charges. The occurrence of fighting and sparring encounters did not change, but the frequency of jawing increased within each fishing season. Various factors determined salmon caught by a bear per hour of fishing effort: salmon abundance, water levels, time of day, and fishing location. The time of day a bear could fish and its choice of location depended on its ability to gain and defend a profitable site. Fishing success was directly correlated with social status, but differences in success are probably unimportant in terms of individual fitness except when salmon are relatively scarce. Changes in encounter intensity over time had no detectable effect on fishing success. Salmon abundance, however, resulted in a further reduction of agonistic encounter intensity and an increase in nonagonistic encounters. Bear social relationships were governed largely by variations in resource abundance. Despite energetic and psychological costs imposed by the bear concentration on individual animals, salmon were evidently sufficiently numerous that these costs were outweighted by returns in protein. Dominance relationships at McNeil Falls did not correspond to predictions of classical dominance theory. This may have been partially attributable to the fact that bears in aggregations derive no benefits from tacit acceptance of subordinate roles; a bear's alternatives were to compete and gain access to food or, if unsuccessful, to try elsewhere. To pose the question if normally solitary bears can adapt behaviorally to efficiently exploit a localized source of food may have been inappropriate. Alternatively, bears can be viewed as occupying and defending areas akin to small territories, with their behavior explicable in terms of energetic costs and benefits based on variations in resource abundance.

The purposes of this paper are threefold: 1) To provide a justification for the increased use of native plants in mountain land development, not only in northeastern Utah, but in the entire western United States. 2) To investigate and delineate what the physical needs of a plant materials list are. 3) To provide a nearly comprehensive list of basically unused plants native to northeastern Utah and to highlight their landscaping potentials based on the earlier investigation. Also touched upon, to help landscape architectural students and professionals alike, are two cursory case studies and a chapter which deals briefly with the problems of nursery supply of native plants and the potential and future research.

Due to the significant threats posed by nonnative fish species worldwide, it is important to understand how life-history strategies of individual species interact with environmental conditions to explain the success or failure of nonnative fish invasions. Brown trout are prolific invaders, but often exhibit upstream distributional limits in Intermountain West streams, potentially due to a maladaptive reproductive life-history strategy influenced by hydrologic conditions in high-elevation areas. We used redd counts, egg survival experiments, and temperature modeling to investigate the reproductive life-history strategy of brown trout and its potential for success along an elevational stream gradient. We documented brown trout spawning in stream reaches at elevations higher than where we typically encounter brown trout during summer electrofishing surveys, indicating the potential for upstream invasion. We observed a decline in egg survival at higher elevation, cooler water sites, but did not document complete recruitment failure at these sites, again indicating the potential for successful invasion at this life-stage. Temperature data indicate that during most years, incubating brown trout eggs would likely fail to emerge from the gravel prior to peak spring flows in these high-elevation stream reaches, suggesting that damaging spring floods may cause significant egg and sac-fry mortality at high elevations, and may determine invasion success in these areas. Our results highlight the importance of identifying specific mechanisms of recruitment failure in order to better predict nonnative fish invasions in the future.

Bibliography: leaves 131-150.