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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.
101

The use and effectiveness of information system development methodologies in health information systems / Pieter Wynand Conradie.

Conradie, Pieter Wynand January 2010 (has links)
Abstract The main focus of this study is the identification of factors influencing the use and effectiveness of information system development methodologies (Le., systems development methodologies) in health information systems. In essence, it can be viewed as exploratory research, utilizing a conceptual research model to investigate the relationships among the hypothesised factors. More specifically, classified as behavioural science, it combines two theoretical models, namely the Unified Theory of Acceptance and Use of Technology and the Expectancy Disconfirmation Theory. The main aim of behavioural science in information systems is to assist practitioners (Le., social actors) in improving business processes and competitiveness, thus the effective use of information systems. A wider view of behavioural science incorporates other social actors (e.g., end users) and organisational actors (e.g., executives). In health information systems, the effective use of information systems is especially relevant Health information systems are vital in the area of health care, since only by having access to pertinent health information, can the correct decisions relating to diagnostics and curative procedures be made. The use of systems development methodologies in health information systems development is therefore crucial, since they can make the development process more effective, while improving software quality. By empirically evaluating the conceptual research model, utilizing a survey as the main research method and structural equation modelling as the main statistical technique, meaningful results were obtained. Focussing on the factors influencing the individual's behavioural intent, it was found that the compatibility of systems development methodologies to the developer's pre-existing software development style is vital. Furthermore, performance expectancy, self-efficacy, organisational culture, policies, customer influence, voluntariness and facilitating conditions, all directly influenced the use of systems development methodologies, with policies and customer influence playing a significant role, especially in relation to health information systems. No significant direct effects or indirect effects could be established for the factors effort expectancy, personal innovativeness and social influence. It appears that individuals working in the health care software development discipline are more autonomous, less influenced by others. Also, the lack of support for the factor effort expectancy may indicate that systems development methodologies have entered a mature state, with less concern on the effort required for use. Furthermore, with regard to effectiveness and the continued use of information systems methodologies, satisfaction had a significant direct effect, with confirmation having a significant indirect effect. Keywords: behavioural science; conceptual research model; direct effect; exploratory research; Expectancy Disconfirmation Theory; indirect effect; Unified Theory of Acceptance and Use of Technology; structural equation modelling; survey; systems development methodologies. / Thesis (Ph.D. (Computer Science))--North-West University, Potchefstroom Campus, 2010.
102

The development and empirical evaluation of an work engagement structural model

Van Deventer, Megan 04 1900 (has links)
Thesis (MComm)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Work Engagement is one construct of many that forms part of the complex nomological network of constructs underlying the behaviour of working man2. Work Engagement is an important construct both from an individual as well as from an organisational perspective. Human resource management interventions aimed at enhancing Work Engagement aspire to contribute to the achievement of the organisation’s primary objective and the well-being of the organisation’s employees. Such interventions will most likely also be valued by individuals within the workplace, as individuals will be able to experience a sense of personal fulfilment through self-expression at work. It is therefore essential to gain a valid understanding of the Work Engagement construct and the psychological mechanism that underpins it, in order to design human resource interventions that will successfully enhance Work Engagement. The current study raises the question why variance in Work Engagement exists amongst different employees working in different organisational contexts. The research objective of the current study is to develop and empirically test an explanatory Work Engagement structural model that will provide a valid answer to this question. In this study, a comprehensive Work Engagement structural model was proposed. An ex post facto correlational design with structural equation modelling (SEM) as the statistical analysis technique was used to test the substantive research hypotheses as represented by the Work Engagement structural model. Furthermore, the current study tested two additional narrow-focus structural models describing the impact of value congruence on Work Engagement by using an ex post facto correlational design with polynomial regression as the statistical analysis technique. A convenience sample of 227 teachers working in public sector schools falling under the jurisdiction of the Western Cape Education Department (WCED) participated in the study. The comprehensive Work Engagement model achieved reasonable close fit. Support was found for all of the hypothesised theoretical relationships in the Work Engagement structural model, except for the influence of the PsyCap*Job Characteristics interaction effect on Meaningfulness and for three of the five latent polynomial regression terms added in the model in an attempt to derive response surface test values. The response surface analyses findings were mixed. Based on the obtained results, meaningful practical recommendations were derived. / AFRIKAANSE OPSOMMING: Werkverbintenis1 is een van ‘n groot verskeidenheid konstrukte wat deel vorm van die komplekse nomologiese netwerk van konstrukte wat die gedrag van die arbeidende mens onderlê. Werkverbintenis word as ‘n belangrike konstruk beskou vanuit ‘n individuele sowel as vanuit ‘n organisatoriese perspektief. Menslike hulpbronbestuurs-intervensies gerig op die bevordering van Werkverbintenis streef daarna om by te dra tot die bereiking van die organisasie se primêre doel sowel as tot die welstand van die organisasie se werknemers. Sodanige intervensies sal waarskynlik ook deur werknemers waardeer word, aangesien sodanige intervensies die kanse verhoog dat individue selfvervulling in hul werk sal ervaar omdat die werk hul die geleentheid bied om hulself in hul werk uit te leef. Dit is gevolglik noodsaaklik om ‘n geldige begrip te ontwikkel van die Werkverbintenis-konstruk en die sielkundige meganisme wat dit onderlê ten einde menslike hulpronbestuurs-intervensies te ontwerp wat suksesvol Werkverbintenis sal bevorder. Die huidige studie stel die vraag aan die orde waarom variansie in Werkverbintenis tussen verskillende werknemers bestaan wat in verskillende organisatoriese kontekste werk. Die navorsingsdoelstelling van die huidige studie is om ‘n verklarende Werkverbintenisstrukturele model te ontwikkel en te toets wat ‘n geldige antwoord op hierdie vraag sal bied. ‘n Omvattende Werkverbintenis strukturele model is in hierdie studie voorgestel. ‘n Ex post facto korrelatiewe ontwerp met strukturele vergelykingsmodellering (SVM) as die statistiese ontledingstegniek is gebruik om die substantiewe navorsingshipotese soos voorgestel deur die Werkverbintenis strukturele model te toets. Die huidige studie het voorts twee addisionele nouer-fokus strukturele modelle getoets wat die impak van waardekongruensie op Werkverbintenis beskryf deur middel van ‘n ex post facto korrelatiewe ontwerp met polinomiese regressie-ontleding as statistiese ontledingstegniek. ‘n Geriefsteekproef van 227 onderwysers wat in openbare skole werksaam is wat onder die beheer van die Wes Kaapse Department van Onderwys val (WKDO) het aan die studie deelgeneem. Die omvattende Werkverbintenis-model het redelik goeie pasgehalte getoon. Steun is gevind vir all die voorgestelde teoretiese verwantskappe in die Werkverbintenis strukturele model, behalwe vir die invloed van die Sielkundige kapitaal*Werk eienskappe-interaksie-effek op Betekenisvolheid en vir drie van die vyf polinomiese latente regressie-terme wat in die model ingesluit is in ‘n poging om responsoppervlakte-waardes af te lei. Gemengde resultate is verkry vir die responsoppervlakte-ontleding. Betekenisvolle praktiese aanbevelings is gemaak op grond van die navorsingsresultate.
103

The value base of water governance in the Upper Paraguay River basin, Mato Grosso, Brazil

Schulz, Paul Christopher January 2017 (has links)
Values have been identified as important factors that guide decision-making and influence preferences in water governance. Comparing the values reflected in water governance decisions with the values held by stakeholders and the general public may inform the debate on the political legitimacy of water governance. The research presented in this PhD thesis draws on multiple research traditions on values, ranging from ecological economics and political ecology to social and environmental psychology, to investigate the value base of water governance in the Upper Paraguay River Basin, in the state of Mato Grosso, Brazil. It first introduces a novel conceptual framework that integrates these various research traditions and suggests that water governance is closely related to the fundamental values, governance-related values, and assigned values of stakeholders and actors in water governance more generally. These different types of values vary in their level of abstractness, as well as in their ‘locus’, i.e. where the valuing person locates them, and are hypothesised to be closely interrelated in a hierarchical structure, with fundamental values being the most abstract type of values. Water governance, in turn, is defined as the synthesis of water policy (the ‘content’ of decisionmaking), water politics (the ‘power play’ between actors) and water polity (the institutional framework). The thesis then proceeds to apply this novel conceptual framework in a case study on stakeholders’ values in the Upper Paraguay River Basin, and investigates the relationship of their values with their preferences regarding the construction of the Paraguay-Paraná Waterway through the Pantanal wetland, in the south of Mato Grosso. This water infrastructure project has a long history of conflict attached to it, as it might impact the hydrology and ecology of the Pantanal, the world’s largest tropical freshwater wetland and UNESCO biosphere reserve, while at the same time benefitting Mato Grosso’s rapidly growing agribusiness sector by lowering the cost of soybean exports. Based on 24 semi-structured interviews with relevant stakeholders, it was found that supporters and opponents possess different, clashing ‘value landscapes’ (i.e. groups of related values), which may explain the protracted nature of the conflict around the construction of the waterway, while at the same time highlighting political legitimacy deficits of the project. This research was followed up by a quantitative study with members of the general public (n=1067), which sought to measure and test the assumption that we can empirically identify such clashing value landscapes, and their relationship with preferences for or against the Paraguay-Paraná Waterway. Using structural equation modelling (SEM), statistically significant links between people’s values and their preferences in water governance could indeed be found, as well as between different types of values, which formed two contrasting value landscapes. This suggests that water governance conflicts may in part be explained by the presence of different value landscapes among involved actors, which may include even the most abstract level of fundamental values. The research presented in this thesis thus contributes to interdisciplinary debates on the role of values for water governance from multiple conceptual, as well as methodological perspectives. Additionally, through its application to a concrete case study, it highlights the policy relevance of such research, as addressing conflicts in water governance and examining alternative policy options may require a more explicit consideration of the values of the actors involved.
104

Towards the formation and measurement of ethnic price perception

Mendoza, Jose January 2016 (has links)
This research is the outcome of a preeminent interest in the topic of price perception. Pointedly, the perception of prices is part of the purchasing process, the same willingness to pay and the actual purchase behaviour, and is indubitably a perceptual construct. As such, perception is problematic to measure as it does not relate to an observable behaviour. On the other hand, pricing is regarded as an important variable in the marketing mix. This research contributes to theory by augmenting the current knowledge on the perception of prices including the methods used in the measurement of such perception. Moreover, this research addresses a gap in the understanding of how diverse ethnic groups perceive prices. The relationship set in this study between ethnicity and price perception is thought-provoking as it contributes to the current discussion around diversity in the marketplace. For example, the literature shows advances in areas such as multicultural and ethnic marketing and this research makes a significant contribution to these areas from price perception. Accordingly, this study involved a systematic review of the literature and presented a framework that suggested that the formation of price perception is affected by external factors such as culture and ethnicity. Furthermore, a qualitative study examined the formation of price perception around ethnic groups. Next, this research used a quantitative study that sought differences in price perception among ethnic groups. Thus, the quantitative study used a price perception scale (Lichtenstein et al., 1993) and a choice-based conjoint analysis. Also, the study adopted structural equation modelling (SEM) to measure differences among scales and the multinomial logit model to analyse the choice-based conjoint analysis. The findings of both the quantitative and the qualitative studies link to the systematic review and support the framework for the formation and measurement of price perception originally proposed.
105

Pulsos de inundação, padrões de diversidade e distribuição de espécies arbóreas em uma floresta ribeirinha no sul do brasil

Budke, Jean Carlos January 2007 (has links)
Formações ribeirinhas são áreas de transição entre os sistemas terrestre e aquático, caracterizadas por elevada heterogeneidade ambiental e por um amplo espectro de elementos biológicos e valores socioeconômicos. Contrário às grandes bacias hidrográficas, onde geralmente os pulsos de inundação são sazonais, os rios de pequeno porte apresentam regimes de inundação freqüentemente imprevisíveis, onde os gradientes de perturbação podem ser expressos pela razão direta entre intensidade, duração e freqüência. Considerando a distribuição de grupos ecológicos ao longo de um gradiente de inundação e as relações entre distúrbio e variáveis ambientais, o presente trabalho teve como objetivo avaliar os padrões de riqueza e diversidade de espécies arbóreas em um rio com regime de inundações não-previsível. O estudo foi realizado próximo à foz do rio Botucaraí (30º 01’S e 52º 47’W), em quatro parcelas de 1 ha, situadas em diferentes cotas de elevação. Cada parcela foi dividida em 10 transecções contíguas de 10 × 100 m, paralelas à margen do rio, sendo cada transecção posteriormente subdividida em unidades amostrais de 10 × 10 m. Em cada parcela, todos os indivíduos arbóreos vivos com perímetro à altura do peito (pbh) ≥ 15 cm foram amostrados. Coletas superficiais de solo (0 – 20 cm de profundidade) foram realizadas, bem como um detalhamento topográfico das parcelas. A freqüência de distúrbio em cada unidade amostral foi definida a partir da interpolação de cota topográfica de cada unidade amostral com os pulsos de inundação para o período de 1981–2004. Técnicas multivariadas de ordenação e classificação foram aplicadas, a fim de explorar as relações entre distribuição de espécies arbóreas, grupos ecológicos de regeneração, estratificação e dispersão com as variáveis ambientais. Uma modelagem por equações estruturadas definiu um modelo significativo entre freqüência de distúrbio, biomassa e variáveis ambientais sobre a variação na riqueza de espécies. Foram amostrados 5.779 indivíduos arbóreos de 37 famílias botânicas. A interação entre distúrbio e biomassa revelou um pico de riqueza de espécies com o aumento da biomassa e a diminuição da freqüência de distúrbios. O modelo estrutural final explicou 79% da variação na riqueza de espécies e 67% na variação sobre biomassa. A análise dos grupos ecológicos revelou menor estratificação vertical em direção às áreas mais inundáveis. Estas áreas também apresentaram maior proporção de indivíduos de espécies pioneiras e dispersão autocórica. Variações florísticas ao longo do gradiente sugerem que a seleção de habitat influencia os padrões de distribuição das espécies, favorecendo histórias de vida com características generalistas, em decorrência de um regime de inundações não-previsível. / Riverine systems are transitional areas between land and aquatic ecosystems that present high environmental heterogeneity and including a wide array of socio-economic and biological values. In large hydrographic basins, flood pulses are seasonal and currently predicted which differ substantially from small rivers, where flood pulses are unpredictable and should be referred as a direct interaction of intensity, duration and frequency. By analyzing the distribution of ecological groups across a flood gradient and the relationships among disturbance and environmental variables, the present work addressed to analyze tree species richness and diversity in a small river with unpredictable flood regime. The survey was conducted in the lower sector of rio Botucaraí (30º 01’S e 52º 47’W) where we installed four 1 ha plots across different topographical sites. Each plot comprised ten contiguous 10 × 100 m transects, parallels to the river margin and then, each transect was subdivided in 10 × 10 m sampling units. In each plot we sampled all individual living trees having at least 15 cm of perimeter at the breast height (pbh). We collected samples of the topsoil (0–20 cm depth) and we carried out a detailed topographic survey of each plot. We interpolated the topographical position of each sampling unit and inundation records from 1981–2004 to obtain a disturbance frequency to each position. We applied multivariate ordination and grouping techniques to seek for relationships among environmental variables, tree species distribution and ecological groups of regeneration, stratification and dispersal. A structural equation modelling improved a significant model among flood frequency, biomass and environmental variables over species richness. Field inventory yielded a total of 5,779 trees belonging to 96 species and 36 families. The interaction between disturbance and biomass revealed a species richness peak with higher biomass and lower disturbance frequency. The final structural model explained 79% of variance in species richness and 67% of variance in biomass. The ecological groups’ analyses revealed lower vertical stratification toward frequently inundated areas. Moreover, these sites presented higher proportion of pioneer and autochorous trees. Floristic changes across the gradient suggest that habitat selection influences species distribution patterns, by selecting generalized live history traits due to the unpredictable flooding regime.
106

The relationship between organisational trust and quality of work life

Van der Berg, Yolandi 02 1900 (has links)
Recent organisational changes have refocused attention on the productivity and performance of sales representatives and consequently brought about a re-evaluation of the QWL these employees experience, as well as their trust in the organisation to support them. Responses to an internet-based survey methodology were analysed using quantitative techniques and structural equation modelling. Results confirm a positive relationship between Managerial Practices and Organisational Trust, and a lower relationship between the dimensions of Personality and Organisational Trust. A positive relationship was noted between QWL and Managerial Practices, and a lower relationship between QWL and the Personality constructs. This study accentuates the importance of management to be aware of the trust employees have in the organisation as well as their experience of QWL, as it seems as though the Personality traits and Managerial Practices of managers influences both the trust relationship and QWL experienced by employees. / Industrial and Organisational Psychology / M.A. (Industrial and Organisational Psychology)
107

The relationship between organisational culture and occupational health

Nel, Mari-Lize 03 1900 (has links)
The aim of the study was to determine whether there is a relationship between organisational culture and occupational health. The General Health Questionnaire and the South African Culture Instruments were used for this purpose. Structural equation modelling (SEM) was used for this purpose. The study focused on clarifying the two concepts and their impact on the organisation. The effects of general health factors were determined in the organisation under investigation. The existing organisational culture was also investigated. In conclusion, the assumption that occupational health can have an impact on organisational health, or vice versa, was confirmed. / Industrial and Organisational Psychology / MCom (Industrial and Organisational Psychology)
108

An investigation of Locke's model of work motivation for the financial services-industry

Olivier, Lynette Dianne 01 1900 (has links)
This research empirically investigates Locke's (1997) model of work motivation by means of quantitative research. The OCQ consisting of three tiered questionnaires was constructed based on Locke's model. OCQ-Tierl deals with core components of Locke's model. OCQ-Tier2 determines which factors caused the incidence of dissatisfaction in OCQ-Tierl. OCQ-Tier3 enables the identification of corrective actions. The OCQ was administered to financial services employees. The results were analysed and Locke's model was tested by means of structural equation modelling using the AMOS graphics programme. The results indicated that the model, suggesting causal links between components within OCQ-Tierl, could not be confirmed. A better fit was found at OCQ-Tier2 and OCQ-Tier3. In testing the causal links across the three tiers per component, the models did not fit the data for "personal actualisation" and "goal achievement". Moderate confirmation of the models was found in the case of "goal setting" and "goal behaviour" across the three tiers after some adaptations were made to the models on the basis of "modification indices", suggested by AMOS. A reasonably good fit was found for the models across the three tiers for "quality of work life". The level of correlation between factors was high because of this, and in some cases some of the factors were merged. Modification indices in the statistical output suggested that improvement was possible if covariance between error terms in the model was allowed. This suggested possible systematic sources of covariance between items not accounted for by the factors in the models. As confirmed by the Cronbach Alpha coefficients within tiers and across tiers, the general level of internal consistency was very high. Possibly response set and response style were the cause of this. This made the testing of models difficult in the present study. So too was it difficult to draw a conclusion about the internal consistency reliability of the measurement of each component across the three tiers, because the high Cronbach coefficients may to some extent be due to the indiscriminate high correlations between items / D.Litt. et Phil. (Industrial Psychology)
109

Mediators of transdiagnostic psychological treatments for eating disorders

Sivyer, Katy January 2017 (has links)
Cognitive behaviour therapy and interpersonal psychotherapy are the leading treatments for eating disorders. Little is understood regarding their mechanisms of action. The research described in this thesis investigated the purported mechanisms of action of two transdiagnostic versions of these treatments; enhanced cognitive behaviour therapy (CBT-E) and interpersonal psychotherapy for eating disorders (IPT-ED). A series of mediation studies were embedded within a randomised controlled trial comparing CBT-E and IPT-ED in a transdiagnostic sample of patients with eating disorders. An analytic strategy using multilevel and structural equation modelling was used to assess for statistical mediation. Three of the key purported mediators of action of CBT-E (regularity of eating, frequency of weighing, and frequency of shape checking) and the key purported mediator of IPT-ED (interpersonal problem severity) were studied. Only regularity of eating demonstrated a strong case for being a mediator of the effect of CBT-E (on frequency of binge eating). The findings were inconclusive regarding other putative mediators of the effect of CBT-E, and for interpersonal problem severity being a mediator of the effect of IPT-ED. Limitations of the research included the non-optimal choice of measures and non-optimal timing of measurements for establishing temporal precedence. Future research should investigate the mediating role of both cognitive (e.g. interpretation of weight) and behavioural processes (e.g. frequency of weighing) in CBT-E, and the role of interpersonal functioning in CBT-E and IPT-ED. Research should use daily, or session by session measurement to better assess the temporal relationship between the purported mediator/s and the outcome/s. Experimental designs comparing dismantled versions of treatment would also help determine the relative effects that different treatment procedures have on treatment outcome/s.
110

Pulsos de inundação, padrões de diversidade e distribuição de espécies arbóreas em uma floresta ribeirinha no sul do brasil

Budke, Jean Carlos January 2007 (has links)
Formações ribeirinhas são áreas de transição entre os sistemas terrestre e aquático, caracterizadas por elevada heterogeneidade ambiental e por um amplo espectro de elementos biológicos e valores socioeconômicos. Contrário às grandes bacias hidrográficas, onde geralmente os pulsos de inundação são sazonais, os rios de pequeno porte apresentam regimes de inundação freqüentemente imprevisíveis, onde os gradientes de perturbação podem ser expressos pela razão direta entre intensidade, duração e freqüência. Considerando a distribuição de grupos ecológicos ao longo de um gradiente de inundação e as relações entre distúrbio e variáveis ambientais, o presente trabalho teve como objetivo avaliar os padrões de riqueza e diversidade de espécies arbóreas em um rio com regime de inundações não-previsível. O estudo foi realizado próximo à foz do rio Botucaraí (30º 01’S e 52º 47’W), em quatro parcelas de 1 ha, situadas em diferentes cotas de elevação. Cada parcela foi dividida em 10 transecções contíguas de 10 × 100 m, paralelas à margen do rio, sendo cada transecção posteriormente subdividida em unidades amostrais de 10 × 10 m. Em cada parcela, todos os indivíduos arbóreos vivos com perímetro à altura do peito (pbh) ≥ 15 cm foram amostrados. Coletas superficiais de solo (0 – 20 cm de profundidade) foram realizadas, bem como um detalhamento topográfico das parcelas. A freqüência de distúrbio em cada unidade amostral foi definida a partir da interpolação de cota topográfica de cada unidade amostral com os pulsos de inundação para o período de 1981–2004. Técnicas multivariadas de ordenação e classificação foram aplicadas, a fim de explorar as relações entre distribuição de espécies arbóreas, grupos ecológicos de regeneração, estratificação e dispersão com as variáveis ambientais. Uma modelagem por equações estruturadas definiu um modelo significativo entre freqüência de distúrbio, biomassa e variáveis ambientais sobre a variação na riqueza de espécies. Foram amostrados 5.779 indivíduos arbóreos de 37 famílias botânicas. A interação entre distúrbio e biomassa revelou um pico de riqueza de espécies com o aumento da biomassa e a diminuição da freqüência de distúrbios. O modelo estrutural final explicou 79% da variação na riqueza de espécies e 67% na variação sobre biomassa. A análise dos grupos ecológicos revelou menor estratificação vertical em direção às áreas mais inundáveis. Estas áreas também apresentaram maior proporção de indivíduos de espécies pioneiras e dispersão autocórica. Variações florísticas ao longo do gradiente sugerem que a seleção de habitat influencia os padrões de distribuição das espécies, favorecendo histórias de vida com características generalistas, em decorrência de um regime de inundações não-previsível. / Riverine systems are transitional areas between land and aquatic ecosystems that present high environmental heterogeneity and including a wide array of socio-economic and biological values. In large hydrographic basins, flood pulses are seasonal and currently predicted which differ substantially from small rivers, where flood pulses are unpredictable and should be referred as a direct interaction of intensity, duration and frequency. By analyzing the distribution of ecological groups across a flood gradient and the relationships among disturbance and environmental variables, the present work addressed to analyze tree species richness and diversity in a small river with unpredictable flood regime. The survey was conducted in the lower sector of rio Botucaraí (30º 01’S e 52º 47’W) where we installed four 1 ha plots across different topographical sites. Each plot comprised ten contiguous 10 × 100 m transects, parallels to the river margin and then, each transect was subdivided in 10 × 10 m sampling units. In each plot we sampled all individual living trees having at least 15 cm of perimeter at the breast height (pbh). We collected samples of the topsoil (0–20 cm depth) and we carried out a detailed topographic survey of each plot. We interpolated the topographical position of each sampling unit and inundation records from 1981–2004 to obtain a disturbance frequency to each position. We applied multivariate ordination and grouping techniques to seek for relationships among environmental variables, tree species distribution and ecological groups of regeneration, stratification and dispersal. A structural equation modelling improved a significant model among flood frequency, biomass and environmental variables over species richness. Field inventory yielded a total of 5,779 trees belonging to 96 species and 36 families. The interaction between disturbance and biomass revealed a species richness peak with higher biomass and lower disturbance frequency. The final structural model explained 79% of variance in species richness and 67% of variance in biomass. The ecological groups’ analyses revealed lower vertical stratification toward frequently inundated areas. Moreover, these sites presented higher proportion of pioneer and autochorous trees. Floristic changes across the gradient suggest that habitat selection influences species distribution patterns, by selecting generalized live history traits due to the unpredictable flooding regime.

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