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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

POSITIVE AND NEGATIVE ATTITUDES AND SUBJECTIVE NORMS TOWARD PLAGIARISM OF RN TO BSN STUDENTS IN AN ACCELERATED ONLINE PROGRAM

Quartuccio, Katherine E. 20 January 2015 (has links)
No description available.
202

TRANSPORT OF RADON IN STILL WATER

SYAHRIR, SYAHRIR 27 May 2005 (has links)
No description available.
203

Predicting Student Success: Factors Influencing NCLEX-RN® Rates in an Urban University's Pre-Licensure Programs

Foley, David M. 03 May 2016 (has links)
No description available.
204

Professional identity development in nurses returning for a BSN: A naturalistic inquiry

Caplin, Marcy S. 14 December 2016 (has links)
No description available.
205

Variables Predicting Success in an Advanced Medical-Surgical Nursing Course and the NCLEX-RN for Pre-Licensure Baccalaureate Nursing Students

Strayer, Robert Michael January 2010 (has links)
The purpose of this descriptive, ex post facto study was to examine possible relationships between demographic, pre-programmatic, and programmatic factors with success in a final Advanced Medical-Surgical nursing course and the National Council Licensure Examination for Registered Nurses, as well as their predictive abilities. Data were obtained from the academic records of 209 full-time and part-time nursing program graduates who completed an upper-division baccalaureate nursing degree at a mid-Atlantic private urban university. Descriptive and inferential analyses were utilized to discover possible relationships between the two dependent variables and the various independent variables in groupings suggested by Carroll's (1963) model of School Learning. Two models were derived to predict success in the nursing program as evidenced by successful completion of the final Advanced Medical-Surgical nursing course and passing the NCLEX-RN on the first attempt. The first model identified age at entrance to the nursing program and repeating a science course as the two factors that explained approximately 49% of the variance in the Advanced Medical-Surgical course performance. The second model was able to predict 97.2% correctly those graduates who would be successful on the NCLEX-RN, and only identify 43.8% of those candidates likely to fail. The overall classification ability by the model was 89%. Implications for nursing educators are that more attention needs to be given to admission policies/procedures, and that students entering nursing programs require routine standardized evaluation, identification and remediation of nursing content gaps in order to be successful throughout their nursing studies and ultimately on the NCLEX-RN. / Educational Psychology
206

BPN暨RN神經網路與向量誤差修正模型對國內債券價格之預測績效 / Exploring the Relative Abilities of Neural Networks and VECM in Forecasting Taiwan's Bond Price

紀如龍, Jih, Ru-Long Unknown Date (has links)
本研究計畫探討以RN神經網路模型預測國內債券價格的效度。目前一般用於財務預測的神經網路論著主要為BPN模型,惟BPN模型有其限制,所以本研究計畫將(1)分析比較統計計量模型,BPN神經網路,RN神經網路系統對國內公債價格之預測績效。(2)分析不同時期的預測能力,找出景氣和預測變數的關係,同時將比較各個時期統計計量模型和神經網路模型是否同時有效, 抑或有些有效, 有些無效,以探討各工具是否具有互補性或替代性。並探討預測績效是否受到背後經濟環境的影響。 我們研究對象為國內公債,其每日交易資料取樣時間自民國八十一年開始。影響債券價格的因素可拆解成實質利率,預期通貨膨脹率和風險貼水三層面,本研究總體變數之選取,亦循此三項範疇以求周延。 本研究之研究成果對理論及實務應用將有下列三項預期貢獻:(1)比較不同其常的債券在不同景氣狀況下,各不同預測模型的預測效度差異,探討各時期各工具之預測能力,可提供投資實務界對預測工具之選擇,應用與搭配。(2)對債券報酬率預測研究,分析總體變數,利率風險等變數對債券報酬率的影響,可進一步暸解影響債券價格的相關因素及程度。(3)以往神經網路應用在財務預測領域上, 皆以BPN 神經網路為主,此處引進RN神經網路,比較兩者的表現,可提供學術理論界之驗證。 / This research project empirically investigates the accuracy of Reasoning Neural Networks (RN) in forecasting Taiwan's bond prices. We explore (1) the relative predictive abilities of Vector Error Correction Model (VECM), which serve as a representative econometric model, Back Propagation Neural Networks (BPN), which is adopted by most current studies in the application of neural networks in finance, and RN, and (2) th3 potential variations in the three models' predictive power in different phases of economic cycle. Specifically, we aim to study if the three models substitute or complementone another. In addition, we explore the extent to which the relativepredictive abilities of the three models varies with underlying macroecomonic factors. The explanatory variables adopted in this study include all potential drives to (real) risk-free rate, expected inflation rate, and riskspremiums. In this study, we examine the government bond terms to maturity,coupon rate, and prices of government bonds during 1992-1995. This project would contribute to both academic and application researchin the following three aspects : (1) Few, if any , prior study explores whether and how various neuralnetworks and/or eco- nomic models perform under different macro-economicvariables. Our empirical results may indicate an appropriate model ( ormodels ) to improve forecasting of bond prices. (2) This study shows how RN, BPN, and VECM models perform in forecastinggovernment bonds yields to maturity. (3) The BPN model prevails in financial forecasting. Nevertheless, BPNis subject to a few short comings and may thus be a sub-optimal model. This study analyzes if RN is more cost-effective in forecasting bond prices than BPN.
207

Competitividade de destinos tur?sticos e o imperativo sustent?vel: avalia??o de dimens?es e atributos condicionantes no P?lo Costa das Dunas, RN, Brasil / Competitiveness of tourist destinations and the sustainable imperative: an evaluation of dimensions and attributes constraints on Polo Costa das Dunas, RN, Brazil

Cerqueira, Liz Rodrigues 30 October 2010 (has links)
Made available in DSpace on 2014-12-17T15:51:28Z (GMT). No. of bitstreams: 1 LizRC_DISSERT.pdf: 4677127 bytes, checksum: 6c4dcd06c105dcf6dfd1ee295d119df9 (MD5) Previous issue date: 2010-10-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Being available as a tourist destination is a necessary condition but not enough for the expansion and success of tourism activity. To be successful, tourism requires investment, inputs, appropriate planning and management, like any other economic activity. A fundamental goal of the destination management is to understand how the competitiveness of a tourist destination can be improved and sustained. Competitive position of tourism can be measured and assessed by various models. Evaluating the indicators of competitiveness of a tourist destination involves a multivariate analysis, ranging from issues directly related to tourism activity itself to the indirect factors. These are elements that are interrelated and that together will point out the competitive condition of this destination. From the definition and characterization of competitiveness, sustainability and management in the context of tourist destinations, understood as the main concepts of this study, we present the main theoretical and methodological models of assessment of competitiveness of tourist destinations in the literature and represent the state of the issue in the scientific treatment of the subject. These models, designed by researchers from several countries and applied in different tourist destinations, are confronted about their structure, indicators considered and localities in which they were applied. The aim of this study was to know and evaluate the condition of tourist competitiveness of the destination P?lo Costa das Dunas, from the constraints attributes of superior performance of the evaluation model of tourist competitiveness of destinations Competenible, suggested by Mazaro, and that suit the requirements of international market aware of the strength and importance of sustainability. The condition of competitiveness of tourist destination in Rio Grande do Norte P?lo Costa das Dunas was moderate. The competitive strengths and weaknesses of the destination P?lo Costa das Dunas revealed through the dozens of sustainable attributes of the model Competenible showed guidelines and initiatives that can be taken to guide strategic decisions related to their planning and management. Thus, this study should serve as support for strategic planning and long-term management of the sector and as a crucial tool for making decisions related to public policies, sectoral investments, monitor processes, strategic planning, direction and control of the local and regional tourism development of destinations / Estar dispon?vel como destino tur?stico ? uma condi??o necess?ria, mas n?o suficiente para a expans?o e ?xito da atividade do turismo. Para ser bem-sucedido, o turismo requer investimentos, insumos, planejamento e gest?o adequados, como qualquer outra atividade econ?mica. Um dos objetivos fundamentais da gest?o de destino ? entender como a competitividade de um destino tur?stico pode ser melhorada e sustentada. A posi??o competitiva do turismo pode ser mensurada, medida e avaliada por diversos modelos. Avaliar os indicadores da competitividade de um destino tur?stico envolve uma an?lise multivariada, que vai desde aspectos ligados diretamente a atividade do turismo em si a fatores indiretos. Trata-se de elementos que se inter-relacionam e que, juntos, v?o apontar a condi??o competitiva desse destino. A partir da defini??o e caracteriza??o da competitividade, sustentabilidade e gest?o no ?mbito dos destinos tur?sticos, entendidos como os principais conceitos deste estudo, s?o apresentados os principais modelos te?ricos e metodol?gicos de avalia??o de competitividade de destinos tur?sticos da literatura atual e representam o estado da quest?o no tratamento cient?fico do tema. Tais modelos, concebidos por pesquisadores de diversos pa?ses e aplicados em diferentes destinos tur?sticos, s?o confrontados quanto a sua estrutura, indicadores considerados e localidades em que foram aplicados. O objetivo deste estudo foi conhecer e avaliar a condi??o de competitividade tur?stica do destino P?lo Costa das Dunas, a partir dos atributos condicionantes de desempenho superior do modelo de avalia??o da competitividade tur?stica de destinos Competenible, proposto por Mazaro, e que se ad?quam ?s exig?ncias do mercado internacional consciente da for?a e import?ncia da sustentabilidade. A condi??o de competitividade do destino tur?stico potiguar P?lo Costa das Dunas foi moderada. As potencialidades e debilidades competitivas do destino P?lo Costa das Dunas reveladas atrav?s das dezenas de atributos sustent?veis do modelo Competenible apontaram lineamentos e iniciativas que podem ser tomadas no sentido de orientar decis?es estrat?gicas relacionadas ao seu planejamento e gest?o. Nesse sentido, este estudo deve servir como suporte ao planejamento estrat?gico e de gest?o a longo prazo do setor e como instrumento determinante para a tomada de decis?es relacionadas ?s pol?ticas p?blicas, investimentos setorial, monitoramento dos processos, planejamento estrat?gico, direcionamento e controle do desenvolvimento tur?stico local e regional de destinos
208

Análise sistêmica da cadeia produtiva da polpa de frutas dos territórios Açú-Mossoró e sertão do Apodi (RN) / Systemic analysis production chain in pulp fruit territories Açu-Mossoró and sertão Apodi (RN)

Oliveira, Isabelle Almeida de 25 February 2015 (has links)
Made available in DSpace on 2016-08-11T14:41:33Z (GMT). No. of bitstreams: 1 IsabelleAO_DISSERT.pdf: 1415862 bytes, checksum: 63b840c911ae8d800331e1f2a4329a7b (MD5) Previous issue date: 2015-02-25 / This thesis is part of a set of studies about the rural areas and family farming, considering its aspects in the economic structure, value addition, organizing group and insertion in the marketplace. There's always been missing a lack of public policies for the family farming, however, during these last ten years there have been issued for those lands significant amounts of funds, especially for small production structures. Although those structures constitute one of the most interesting and promising experiences to the countryside, they have worked in disabilities, and its economic dynamism has not happened. In this context, the main matter is how the supply chain of fruit pulp forms has made a set of initiatives that can build a promising new endogenous development format, but it has not been able enough to promote economic dynamism of the lands in Açu-Mossoró and in the countryside of Apodi (RN). By being aware about that, we tried and analyzed in a systematic way the fruit pulp production chain as an environment of innovation and production of new things, considering its role play in the diversification of the local economies, and in taking forward to the lands of Açu-Mossoró and in the countryside of Apodi (RN). As for the methodology to perform the data collecting we've chosen to use the primary data, which was consisted of a questioning in the units of fruit pulp production identified in the studied areas. As a result, the survey revealed that the fruit pulp chain is largely present in the countryside of Apodi than in Acu-Mossoró due to a larger number of production units, more diversified in the family farming, but besides that they have built a better social organization and consolidated group, which led them into their insertion into different markets. However, deficiencies have been identified, such as the lack of trade certification which limits them in the market insertion. This survey found that the lack of infrastructure is related to the lack of credit, technical and technology assistance, leading the farmers to develop their own new strategies and create their own new policies to try and access their join into the markets / Essa dissertação se insere no conjunto de estudos sobre o meio rural e a agricultura familiar, considerando aspectos relacionados com sua estruturação econômica, agregação de valor, organização coletiva e inserção em mercados. Para a agricultura familiar sempre houve carência de políticas públicas, no entanto, nos últimos dez anos têm sido destinados somas significativas de recursos financeiros para os territórios, especialmente para estruturas produtivas de pequeno porte. Apesar dessas estruturas constituírem uma das experiências mais interessantes e promissoras para o meio rural, elas têm funcionado com deficiência, e a dinamização econômica não tem acontecido. Neste contexto, a questão central é como a cadeia produtiva de Polpa de Frutas forma um conjunto de iniciativas que constrói um novo e promissor formato de desenvolvimento endógeno, porém não tem sido capaz o suficiente para promover a dinamização econômica dos territórios Açu-Mossoró e Sertão do Apodi (RN)? Em face disso, buscou-se analisar, de forma sistêmica, a cadeia produtiva de Polpa de Frutas como ambiente de inovação e produção de novidades, considerando o seu papel na diversificação das economias locais, e na dinamização dos territórios Açu-Mossoró e Sertão do Apodi (RN). Quanto à metodologia para efetuar a coleta de dados optou-se pelos dados primários, que consistiu na aplicação de questionários nas unidades de produção de Polpa de Frutas identificadas nos territórios estudados. Como resultados, a pesquisa revelou que a cadeia de polpa de frutas está mais presente no Território Sertão do Apodi do que no Açu-Mossoró, devido a um número maior de unidades produtivas, de uma agricultura familiar mais diversificada, como também possuir uma organização social e coletiva mais consolidada, o que propiciou a inserção em mercados diferenciados. Porém, foram detectadas deficiências, a exemplo da falta de certificação o que limita a inserção em mercados. A pesquisa apontou que a carência de infraestrutura está relacionada com a falta de crédito, assistência técnica e tecnologia, o que leva os agricultores familiares a elaborar estratégias de inovação e da criação de novidades para acessar políticas e se inserir em mercados
209

Aplicação de bioestimulantes e espaçamento de plantio na produção e conservação pós-colheita de melão / Biostimulants application and spacing of planting in the production and melon postharvest conservation

Góes, Glêidson Bezerra de 25 February 2015 (has links)
Made available in DSpace on 2016-08-12T19:18:32Z (GMT). No. of bitstreams: 1 GleidsonBG_TESE.pdf: 1056498 bytes, checksum: 1b634839425bf45c68c20db5dd97cbbc (MD5) Previous issue date: 2015-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of new technologies aimed at improving the quality of fruit is needed to meet consumer demands and this should remain for a longer time in order to reach distant consumer markets. Thus, this study evaluated the influence of the application of bio-stimulants and spacing of planting the melon postharvest conservation. For this, two experiments were conducted at the Farm Garden, located at Pau-Branco community in Mossoró-RN, to assess the influence of bio-stimulants, application forms and planting space in post-harvest melons conservation. The experiments were divided into two phases: the field and the laboratory. The first experiment evaluated the effect of bio-stimulants and application form in pre-harvest quality and melon postharvest conservation Yellow 'Iracema'. The field phase of this experiment was conducted in a randomized blocks in a factorial scheme with an additional treatment 2 x 2 + 1, two bio-stimulants (Crop Set® and Spray Dunger®), two application forms (sprayed and fertilized) and a control (without product application), with five repetitions. The second experiment evaluated the influence of spacing and biostimulant in the production, quality and melon conservation hybrid Frog Skin Sancho. For the field phase of this experiment, we adopted a randomized blocks in factorial 3 x 2, with three spacing between plants (40, 45 and 50 cm) and two applications of bio-stimulant Crop Set® (with and without), with four replications. In both experiments, the combination of factors constituted the plots where the fruits were sampled for characterization in the laboratory quality during storage. The fruit harvest was performed when they reached commercial maturity, and on this occasion we assessed the number of fruits per plant, number of fruits per meter, average fruit weight and productivity. The laboratory phase of both experiments was conducted in a completely randomized design with split plots in storage time with eight replications. At that stage, one fruit group was characterized, the day after the harvest, and the other were stored in refrigeration chamber regulated at 101ºC and 902% RH, time-lapse of 14, 21, 28 and 35 days. At each time interval, the fruit were evaluated by mass loss (ML), pulp firmness (PF), soluble solids (SS), titratable acidity (TA), reason soluble solids/titratable acidity (ratio), pH, vitamin C (VC) and soluble sugars. The data were submitted to analysis of variance and the significant variables were compared by the Tukey test, and the average of the control treatment compared using the Dunnett test and for the significant variables in the storage life regression analysis was performed. The biostimulants and the application form before the harvest influenced the quality and service life Yellow melon postharvest 'Iracema'. In Yellow melons, the application of bio-stimulant fertigation led to higher average fruit weight and productivity. The fruits of PF decreased during storage, the largest decrease occurred with the application of Spray Dunger® via spraying. The application by fertigation provided greater SS content in fruit, but during the storage period the SS content of the fruits decreased and remained at 35 days levels of 10%. The higher content of soluble sugars was found in the application form via fertigation by applying Crop Set®, but there were decreases of soluble sugar after 35 days of storage. There was a linear increase in VC content during storage. For the melon 'Piel de Sapo' production, quality and conservation of fruit were influenced by crop at different spacings and bio-stimulant. Production variables were not influenced by the application of Crop Set®. However, the number and the weight of commercial fruit per plant increased as increased spacing between plants. The storage of fruit provided an increase in melons ML with application of bio-stimulant, independently of planting space. PF fruit decreased during storage. The planting spacing of 40 cm provides lower SS of fruit than the spacings of 45 and 50 cm / A utilização de novas tecnologias visando à melhoria na qualidade dos frutos é necessária para atender às exigências do consumidor e essa deve permanecer por um tempo maior visando a alcançar mercados consumidores distantes. Dessa forma, este trabalho avaliou a influência da aplicação de bioestimulantes e espaçamento de plantio na conservação pós-colheita de melão. Para isto, foram conduzidos dois experimentos na Fazenda Jardim, localizada na comunidade de Pau-Branco, em Mossoró-RN, para avaliar a influência de bioestimulantes, formas de aplicação e espaçamentos de plantio na conservação pós-colheita de melões. Os experimentos foram divididos em duas fases: campo e laboratório. O primeiro experimento teve por objetivo avaliar o efeito dos bioestimulantes e da forma de aplicação em pré-colheita na qualidade e conservação pós-colheita de melão Amarelo Iracema . A fase de campo deste experimento foi realizada em delineamento experimental em blocos casualizados em esquema fatorial com tratamento adicional 2 x 2 + 1, sendo dois bioestimulantes (Crop Set® e Spray Dunger®), duas formas de aplicação (pulverizado e fertirrigado) e uma testemunha (sem aplicação de produto), com cinco repetições. O segundo experimento teve por objetivo avaliar a influência do espaçamento e aplicação de bioestimulante na produção, qualidade e conservação de melão Pele de Sapo híbrido ˈSanchoˈ. Para a fase de campo deste experimento, foi adotado o delineamento experimental em blocos casualizados em esquema fatorial 3 x 2, sendo três espaçamentos entre plantas (40; 45 e 50 cm) e duas aplicações do bioestimulante Crop Set® (com e sem), com quatro repetições. Em ambos os experimentos, a combinação dos fatores constituiu as parcelas de onde foram amostrados os frutos para caracterização, em laboratório, da qualidade durante o armazenamento. A colheita dos frutos foi realizada quando estes atingiram a maturidade comercial, sendo nesta ocasião avaliados o número de frutos por planta (NFP), número de frutos por metro linear (NFML), peso médio de frutos (PMF) e produtividade (PROD). A fase de laboratório, de ambos os experimentos, foi realizada em delineamento inteiramente casualizado com parcelas subdivididas no tempo de armazenamento com oito repetições. Nessa fase, um grupo de frutos foi caracterizado, um dia após a colheita, e os demais foram armazenados em câmara de refrigeração regulada a 101ºC e 902%UR, por intervalo de tempo de 14, 21, 28 e 35 dias. Em cada intervalo de tempo, os frutos foram avaliadas quanto à perda de massa (PM), firmeza de polpa (FP), sólidos solúveis (SS), acidez titulável (AT), razão sólidos solúveis/acidez titulável (SS/AT), pH, vitamina C (Vit. C) e açúcares solúveis (AS). Os dados foram submetidos à análise de variância, sendo as variáveis significativas comparadas pelo teste de Tukey, e as médias do tratamento testemunha comparadas por meio do teste de Dunnett e para as variáveis significativas no tempo de armazenamento, foi realizada análise de regressão. Os bioestimulantes e a forma de aplicação em pré-colheita influenciaram a qualidade e vida útil pós-colheita de melão Amarelo Iracema . Em melões Amarelo, a aplicação do bioestimulante via fertirrigação propiciou maior PMF e maior produtividade. A FP dos frutos diminuiu durante o armazenamento, o maior decréscimo ocorreu com a aplicação de Spray Dunger® via pulverização. A aplicação via fertirrigação propiciou maior teor de SS nos frutos, mas durante o período de armazenamento o teor de SS dos frutos diminuiu e manteve aos 35 dias teores de 10%. O maior teor de açúcares solúveis foi verificado na forma de aplicação via fertirrigação com a aplicação de Crop Set®, mas houve decréscimos dos AS aos 35 dias de armazenamento. Houve aumento linear no teor de vitamina C durante o período de armazenamento. Para o melão Pele de Sapo , a produção, a qualidade e conservação dos frutos foram influenciadas pelo cultivo em diferentes espaçamentos e aplicação de bioestimulante. As variáveis de produção não foram influenciadas pela aplicação de Crop Set®. Porém, o número e o peso de fruto comercial por planta aumentaram com o aumento do espaçamento entre as plantas. O armazenamento dos frutos propiciou aumento na PM dos melões com aplicação do bioestimulante, independentemente do espaçamento de plantio. A FP dos frutos diminuiu durante o armazenamento. O espaçamento de plantio de 40 cm propiciou média de SS dos frutos inferior aos frutos dos espaçamentos 45 e 50 cm
210

Efeitos de seca prolongada na diversidade beta de assembleias de peixes de um reservatório semiárido / prolonged drought effects on beta diversity of fish assemblages of a semiarid reservoir

Pinheiro, Laura Amélia Pereira 31 July 2015 (has links)
Made available in DSpace on 2016-08-15T20:31:27Z (GMT). No. of bitstreams: 1 LauraAPP_DISSERT.pdf: 738763 bytes, checksum: ebeaf280b69690d2824f0efa4d627ebb (MD5) Previous issue date: 2015-07-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Santa Cruz reservoir suffered interferences in the reduction of the rain level between 2010 and 2014, where the precipitation values were under the expected level in that region, decreasing from 473 mm to 0 mm and resulting in the progressive reduction of the reservoir volume from 94% until 41.9%. So the objective of this study was: (1) test the effect of the reduction level of the water in the reservoir caused by the decreasing of the pluviosity above the beta diversity; (2) investigate spacial and temporal patterns of the beta diversity of the group using dissimilarity indexes based in incidences (β-sor) and abundance (β-bray); (3) investigate the importance of the turnover (β-sim) and nestedness (β-sne) components in the dissimilarities of Sorensen; (4) investigate the importance of the gradiente (β-gra) and balance (β-bal) components in the dissimilarity of Bray-Curtis; (5) evaluate the relations between the measures and components of dissimilarity and the dried gradients (reduction of the water volume and the monthly rains) and longitudinal (gradient dam-river) where the dissimilarities of Sorensen were calculated and so partitioned in components of turnover and nestedness, and also the Bray-Curtis dissimilarity partitioned in components of ballance and gradiente. To evaluate the correlation between the dissimilarity matrix and the dam-river gradient with the dry gradients, it was made multiples regressions in the distance matrix. The average value of the β-sor dissimilarity was from 0.44± 0.15 varying from 0 to 1. The β-sim values shows 56% of β-sor (p=0.001) while the β-sne was 1.4% (p=0.01). The average value of the Bray Curtis dissimilarities was from 0.70± 0.17 varying from 0.09 to 1. The β-bal value shows 12% (p=0.01), where the β-gra value shows 14% (p=0.01). The β-sor matrix was negatively correlated with the pluviosity, however the same was positively correlated with the reservoir volume. The β-sim matrix was negatively correlated with the pluviosity and with the volume of the reservoir while the same was positively correlated with the points distance. The β-sne matrix was positively correlated only with the distance matrix of the points. The β-bray matrix was positively correlated with the distance of the points and the reservoir s volume. The β-bal matrix was negatively correlated with the distances of the points and the pluviosity, while the same was positively correlated with the reservoir s volume. The β-gra matrix was positively correlated with the distance. This research revealed that the dry gradient changes the ecosystem of a tropical reservoir, principally by the turnover of the species and the abundance gradient. / O reservatório de Santa Cruz sofreu a interferência na redução do nível de chuvas de 2010 a 2014, onde os valores de precipitação foram inferiores ao nível médio da região, variando de 473 mm a 0 mm, resultando na redução progressiva do volume do reservatório reduzindo assim de 94% em até 41,9%, com isso, o objetivo da pesquisa foi: (1) Testar o efeito da redução do nível de água do reservatório, ocasionado pela diminuição da pluviosidade, sobre a diversidade beta (2) Investigar padrões espaciais e temporais de diversidade beta das assembleias usando índices de dissimilaridade baseados em incidência (β-sor) e abundancia (β-bray) (3) Investigar a importância dos componentes de turnover (β-sim) e aninhamento (β-sne) nas dissimilaridades de Sorensen (4) Investigar a importância dos componentes de gradiente (β-gra) e balanço (β-bal) na dissimilaridade de Bray-Curtis (5) Avaliar as relações entre as medidas e componentes de dissimilaridade e os gradientes de seca (redução do volume da água e da chuva mensal) e longitudinal (gradiente barragem-rio), onde foram foram calculadas as dissimilaridade de Sorensen e assim particionada em componentes de turnorver e aninhamento, e também a dissimilaridade de Bray-Curtis particionada em componentes de balanço e gradiente. Para avaliar as correlações entre as matrizes de dissimilaridade e o gradiente barragem rio com os gradientes de seca, foi feitas regressões múltiplas em matrizes de distâncias. O valor médio da dissimilaridade de β-sor foi de 0,44± 0,15 variando de 0 à 1 .Os valores de β-sim explicou 56% de β-sor (p=0,001) enquanto o de β-sne 1,4% (p=0,01). O valor médio da dissimilaridade de Bray Curtis foi de 0,70± 0,17, variando de 0,09 à 1, O valor de β-bal explicou 12% (p=0,01), enquanto o valor de B-gra explicou 14% (p=0,01). A matriz β-sor foi correlacionada negativamente com a pluviosidade, no entanto a mesma foi correlacionada positivamente com o volume do reservatório. A matriz β-sim foi correlacionada negativamente com a pluviosidade e com o volume do reservatório, enquanto a mesma foi correlacionada positivamente com a distância dos pontos. A matriz β-sne foi correlacionada positivamente apenas com a matriz de distância dos pontos. A matriz β-bray foi correlacionada positivamente com a distância dos pontos e volume do reservatório. A matriz β-bal foi correlacionada negativamente com a distância dos pontos e com a pluviosidade, enquanto a mesma foi positivamente correlacionada com o volume do reservatório A matriz β-gra foi correlacionada positivamente com a distância. A presente pesquisa evidenciou que gradiente de seca altera o ecossistema de um reservatório tropical, principalmente por turnorver de espécies e gradiente de abundancia

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