Desenvolvimento regional sustentável dos municípios da Amazônia legal: análise de políticas públicas

Dissertação apresentada ao Programa de Pós-Graduação Mestrado em Administração (PPGMAD), da Fundação Universidade Federal de Rondônia (UNIR) como requisito para obtenção do Grau de Mestre em Administração. Orientadora: Profª Drª Mariluce Paes de SouzaO desenvolvimento econômico regional pode ser estabelecido atendendo paradigmas de sustentabilidade, pois quando ocorre sem planejamento, leva comunidades a tomarem decisões prejudiciais à sua cultura e ao seu próprio desenvolvimento social e ambiental, podendo comprometer irreparavelmente o futuro. O Desenvolvimento Regional Sustentável – DRS, como novo paradigma, estabelece a necessidade de racionalização do uso dos recursos naturais, de modo que possam atender às necessidades atuais das populações amazônicas sem comprometer as necessidades das gerações futuras. Sob a perspectiva institucional, observa-se que o tema já é amplamente aceito pelos governos, empresas, organizações não governamentais e a sociedade em geral, haja vista a presença de isomorfismo quando se observa mimetização nas melhores práticas. Este trabalho tem como objetivo avaliar o impacto das políticas públicas de desenvolvimento regional sustentável nos municípios da Amazônia Legal. Esta pesquisa analisa as características dos 771 municípios da Amazônia Legal a partir de 26 indicadores incorporados a um Barômetro da Sustentabilidade composto de nove temas, visando comparar, a partir da qualificação obtida dos municípios, as políticas públicas que mais impactam o Desenvolvimento Sustentável na Região Amazônica, permitindo que gestores e Policy Makers possam atuar, prioritariamente, para atingir com maior eficiência os Objetivos do Milênio na Amazônia Legal. Como resultado, observou-se que as políticas envolvendo os temas educação, renda, tratamento sanitário e tratamento de resíduos são preponderantes para elevar a região ao patamar de sustentabilidade necessário. No entanto, os indicadores de resultado apontam, ainda, baixa eficiência do bem-estar humano e ambiental na Amazônia Legal

Climate changes and the formation of fluvial terraces in central Amazonia inferred from landscape evolution modeling

Climate changes have been considered an essential factor controlling the shaping of the recent alluvial landscapes in central Amazonia, with implications for explaining the biogeographic patterns in the region. This landscape is characterized by wide floodplains and various terrace levels at different elevations. A set of older terraces with ages between 50 and > 200 ka occupy the higher portions of central Amazonia, whereas multiple terraces next to floodplains occur at lower elevations and display ages of a few thousand years. These lower terraces, referred to as middle–lower terraces, reveal what can be perceived as a stochastic pattern both in space and time. Despite the widespread occurrence of these geomorphic features, no process-oriented analysis has been conducted to explain their formation. Here, we develop a landscape evolution model referred to as SPASE (Sedimentary Processes and Alluvial Systems Evolution) to explicitly account for fluvial erosion and deposition in combination with lateral channel migration to explore the controls on terrace development. The model results show that the higher terraces were deposited under the condition of a higher base level for the basins upstream of the confluence between the Solimões and Negro rivers. The subsequent decrease in the base level initiated a phase of gradual incision, thereby resulting in the current fluvial configuration. The model also predicts that high-frequency climate changes resulted in the construction of middle–lower terraces at various elevations which, however, are all situated at lower elevation than the higher terrace levels. Our model shows that dry-to-wet shifts in climate, in relation to the modern situation, yield a landscape architecture where middle–lower terrace levels are better preserved than wet-to-dry changes in climate, again if the current situation is considered as reference. Finally, our results show that fast and widespread landscape changes possibly occurred in response to high- frequency climate changes in central Amazonia, at least since the Late Pleistocene, with great implications for the distribution and connectivity of different biotic environments in the region. Because of this short timescale of response to external perturbations, we suggest that the streams in central Amazonia possibly also respond in rapid and sensitive ways to human perturbations

Provenance and paleocurrents of conglomerates and sandstones of the Santa Barbara Group (Ediacaran) in the Piquiri Valley, Eastern Camaquã Sub-basin, Rio Grande do Sul, Brazil: tectonic implications

The Eastern Camaquã Sub-basin comprises exposures of Eastern border, as the Piquiri Valley, belonging to the Santa Barbara Group (Ediacaran). Stratigraphic studies of facies, depositional systems, provenance and paleocurrentes led to the subdivision of the Santa Barbara Group on Eastern Camaquã Sub-basin in two units: (i) Passo da Capela Formation, formed by turbidites of subaqueous fans; (ii) Rincão dos Mouras Formation, that consists of sandstones and conglomerates of alluvial fans and fluvial braided systems. This article proposes a model of structural highs evolution during the filling of a rift basin. Subaqueous fan conglomerates of Passo da Capela Formation feature framework composition derived the basin (sandstones), indicating autophagy, and rocks of the basement (quartzites, schists, metarhyolites) also occur. Paleocurrent analyses indicate dispersal of sediments toward NNE, compatible with lithotypes of the Porongos Complex (quartzites, metarhyolites, mylonites). Northward, provenance analyses of conglomerates indicate derivation mostly from Syenite Piquiri, but also from other lithologies. This fact suggests a local contribution (clasts of Syenite Piquiri), with little or no transportation. Alluvial conglomerates of the Rincão dos Mouras Formation have diverse provenance. Provenance analysis suggests denudation of the Porongos Complex (basement highs), exemplified by metarhyolites, and of the own basin (sandstones). Middle portion presents clasts of granites/muscovite leucogranites correlated to the Pelotas Batolith, and lithologies of the Porongos Complex. Syenites and trachytes appear in small proportion, as well as sandstones. Provenance and paleocurrent analyses indicate that areas to the east were being uplifted and eroded, such as Pelotas Batolith and Porongos Complex, behaving like basement highs, supplying sediments to the basin. At the top fragments of the Porongos Complex predominate (marbles). Paleocurrent analyses in the Rincão dos Mouras Formation suggest important tectonic control during the filling of the unit, with shifts in sources of debris to the basin and uplift of internal highs. Provenance analysis carried out in all units (i) indicated always adjacent sources to the sedimentary deposits, (ii) demonstrated the sources of debris, and (iii) assisted in the differentiation between Passo da Capela and Rincão dos Mouras formations. The occurrence in this last unit of marble fragments and the considerable increase in the proportion of clasts related to the Encruzilhada do Sul Granite, located ENE of the region of the Piquiri Valley, were two important criteria used to differentiate both units, especially when stratified conglomerates of both are contiguous.A Sub-bacia Camaquã Oriental compreende exposições da borda leste da Bacia do Camaquã, como o Vale do Piquiri, pertencentes ao Grupo Santa Bárbara (Ediacarano). Estudos estratigráficos de fácies, sistemas deposicionais, proveniência e paleocorrentes conduziram à subdivisão do Grupo Santa Bárbara na Sub-bacia Camaquã Oriental em duas unidades: (i) Formação Passo da Capela, formada por turbiditos de leques subaquosos; e (ii) Formação Rincão dos Mouras, constituída por arenitos e conglomerados de leques aluviais e sistemas fluviais entrelaçados. Este artigo propõe formular um modelo de evolução de altos estruturais durante o preenchimento de uma bacia rifte. Conglomerados de leques subaquosos da Formação Passo da Capela apresentam composição do arcabouço derivada da própria bacia (arenitos), indicando autofagia, além de rochas do embasamento (quartzitos, xistos, metarriolitos). Análises de paleocorrentes indicam dispersão dos sedimentos segundo NNE, compatível com litotipos do Complexo Porongos (quartzitos, metarriolitos, milonitos). A norte, análises de proveniência dos conglomerados indicam derivação principalmente do Sienito Piquiri, e também de outras litologias. Esse fato sugere que a proveniência reflete contribuição do embasamento adjacente (clastos do Sienito Piquiri), com pouco ou nenhum transporte. Conglomerados aluviais da Formação Rincão dos Mouras contam com proveniência diversificada. Na base ocorrem clastos metamórficos do Complexo Porongos (metarriolitos) e da própria bacia (arenitos). Análises de proveniência sugerem denudação do Complexo Porongos (altos de embasamento) e da bacia. A porção intermediária apresenta clastos de granitos róseos/muscovita leucogranitos correlacionáveis ao Batólito Pelotas, e litologias do Complexo Porongos. Sienitos e traquitos aparecem em pequena proporção, assim como arenitos. Análises de proveniência, aliadas às de paleocorrentes, indicam que áreas a leste estavam sendo soerguidas e erodidas, como Batólito Pelotas e Complexo Porongos, comportando-se como altos de embasamento fornecedores de sedimentos para a bacia. No topo predominam fragmentos do Complexo Porongos (mármores). Análises de paleocorrentes realizadas na Formação Rincão dos Mouras sugerem controle tectônico importante durante o preenchimento da unidade, com mudanças de fontes de detritos para a bacia e soerguimento de altos internos. As análises de proveniência levadas a efeito em todas as unidades (i) indicaram sempre fonte adjacente aos depósitos sedimentares; (ii) demonstraram as fontes de detritos; e (iii) auxiliaram na diferenciação entre as formações Passo da Capela e Rincão dos Mouras. A ocorrência na Formação Rincão dos Mouras de fragmentos de mármore e o aumento considerável da proporção de clastos do Granito Encruzilhada do Sul, situado a ENE da região do Vale do Piquiri, foi mais um dos critérios utilizados na separação das unidades, sobretudo quando conglomerados estratificados de ambas se acham contíguos

Interpretation software applied to the evaluation of shallow seismic data processing routines in fluvial deposits

High-resolution seismic surveys have been successfully applied in the study of active sedimentary environments in shallow submerged settings, particularly improving the interpretation of sedimentary facies and architectural elements that characterize fluvial rock records. Nevertheless, specific data processing workflows to emphasize sedimentary structures have not been proposed or tested, so that interpretation currently relies on the subjective opinion of individual interpreters, which might lead to biased conclusions. Aiming at the construction of a less biased data processing workflow, we developed a software that analyzes seismic data and performs standardized interpretation by linking individual seismic traces to generate interpreted reflector lines. A dataset acquired with boomer continuous seismic profiler in the sedimentary bed of the Amazonas river in Brazil was processed with a typical sequence of filter and gain (using Seismic UNIX software), as well as a routine of trace interpolation written in GNU Octave. The application of the Standardized Interpreter at different stages of processing enabled the comparison of the resulting interpretation scenarios in terms of the representation of geometries related to internal sedimentary structures, thus leading to the proposition of a workflow adapted to the specific needs of sedimentary structure interpretation from seismic data

Evolução Estratigráfica e paleogeográfica do grupo Santa Bárbara (Ediacarano) na sub-bacia Camaquã Central, RS

In the Central Camaquã Sub-basin, the Santa Bárbara Group (Ediacaran) is over 2,000 m thick, being well exposed in the Minas do Camaquã and Bom Jardim regions. The group is represented by a sucession of marine to coastal sandstones and rhythmites, and alluvial fan conglomerates, disposed in progradational-retrogrational cycles. Detailed stratigraphic studies of paleoenvironments, paleocurrents and provenance have lead to the subdivision of the Group in the central sub-basin into four formations: 1. Passo da Capela Formation: silty-sandy unit composed of outer- and inner- subaqueous fan turbidites and offshore tempestites; 2. Seival Formation: sandstones of coastal deposits, including tidal flat sistems; 3. Rincão dos Mouras Formation: alluvial fan and braided alluvial pebbly unit and 4. João Dias Formation: mainly sandstones interpreted as foreshore and shoreface coastal deposits. These studies have permitted the detailed correlation between the Minas do Camaquã and Bom Jardim regions, thus supporting the proposition of including in the Santa Bárbara Group as defined here, the deposits exposed in the Minas do Camaquã region, traditionally attributed to the Arroio dos Nobres Formation.As exposições do Grupo Santa Bárbara (Ediacarano) na Sub-bacia Camaquã Central são representadas por uma sucessão de depósitos arenosos e rítmicos marinhos/transicionais e depósitos conglomeráticos de leques aluviais, que compõem ciclos progradacionais-retrogradacionais. Nesta sub-bacia, o Grupo Santa Bárbara apresenta mais de 2.000 m de espessura, com excelentes exposições nas regiões das Minas do Camaquã e de Bom Jardim. Estudos estratigráficos de paleoambientes, paleocorrentes e de proveniência realizados nestas regiões possibilitaram a seguinte subdivisão do Grupo Santa Bárbara na Sub-bacia Camaquã Central, a partir da base: 1. Formação Passo da Capela: unidade areno-siltítica subdividida em turbiditos distais de leque subaquoso (Outer-fan), e turbiditos proximais a distais de leque subaquoso (Inner-Fan a Outer-fan) e tempestitos de costa-afora (offshore); 2. Formação Seival: arenitos e siltitos de depósitos litorâneos e de planície de marés; 3. Formação Rincão do Mouras: unidade areno-conglomerática formada por depósitos de leques aluviais e de sistemas fluviais entrelaçados e 4. Formação João Dias: composta principalmente por arenitos interpretados como depósitos litorâneos de antepraia e de face litorânea e tempestitos de face litorânea. Estes estudos permitiram ainda o reconhecimento de uma notável correlação entre as unidades encontradas nestas regiões legitimando, desta forma, a proposta de englobar os depósitos da região das Minas do Camaquã, classicamente relacionadas à Formação Arroio dos Nobres, no redefinido Grupo Santa Bárbara

Andean Tectonics and Mantle Dynamics as a Pervasive Influence on Amazonian Ecosystem

The Amazonian landscape evolution is the result of the combined effect of Andean tectonism, climate and the Earth’s interior dynamics. To reconstruct the landscape evolution and its influence on paleoenvironmental variations within Amazonia since the Oligocene, we conducted numerical experiments that incorporate different surface and geodynamic processes, reproducing many paleogeographic features as inferred from the sedimentary record. We show that the evolution of the drainage pattern gradually reduced the area of sedimentation derived from the Guiana and Brazilian shields while expanded the Andean derived deposits during the Miocene, affecting the nutrient availability. First order biotic habitats were inferred from these paleogeographical reconstructions, showing an eastward expansion of várzea and terra firme forests and consequent retraction of igapó forests, with a millennial-scale reconfiguration of a mosaic of habitats in the lowlands. We conclude that this dynamism probably guided the observed patterns of speciation in the most biodiverse biome on Earth. © 2019, The Author(s)

Large barchanoid dunes in the Amazon River and the rock record : implications for interpreting large river systems.

The interpretation of large river deposits from the rock record is hampered by the scarcity of direct observations of active large river systems. That is particularly true for deep-channel environments, where tens of meters deep flows dominate. These conditions are extremely different from what is found in smaller systems, from which current facies models were derived. MBES and shallow seismic surveys in a selected area of the Upper Amazonas River in Northern Brazil revealed the presence of large compound barchanoid dunes along the channel thalweg. The dunes are characterized by V-shaped, concave-downstream crest lines and convex-up longitudinal profiles, hundreds of meters wide, up to 300 m in wavelength and several meters high. Based on the morphology of compound dunes, expected preserved sedimentary structures are broad, large-scale, low-angle, concave up and downstream cross-strata, passing laterally and downstream to inclined cosets. Examples of such structures from large river deposits in the rock record are described in the Silurian Serra Grande Group and the Cretaceous S?o Sebasti?o and Marizal formations in Northeastern Brazil, as well as in Triassic Hawkesburry Sandstone in Southeastern Australia and the Plio?Pleistocene I?? Formation in the western Amazon. All these sedimentary structures are found near channel base surfaces and are somewhat coarser than the overlying fluvial deposits, favoring the interpretation of thalweg depositional settings. The recognition of large barchanoid dunes as bedforms restricted to river thalwegs and probably to large river systems brings the possibility of establishing new criteria for the interpretation of fluvial system scale in the rock record. Sedimentary structures compatible with the morphological characteristics of these bedforms seem to be relatively common in large river deposits, given their initial recognition in five different fluvial successions in Brazil and Australia, potentially enabling substantial improvements in facies models for large rivers

Umbria-Marche Basin, Central Italy: A Reference Section for the Aptian-Albian Interval at Low Latitudes

Within the Cretaceous Period, the Aptian-Albian interval (125–99.6 Ma, Ogg et al., 2008) was a critical time on a global scale. This is evident from 1) changes in the nature of the ocean-climate system brought about by increased ocean crust production coupled with active midplate and plate margin volcanism in a shifting paleogeography (Skelton et al., 2003); 2) cyclic deposition and preservation of common “black shales”, some of them termed Oceanic Anoxic Events(OAE1a to OAE1d) (Schlanger and Jenkyns, 1976; Arthur et al., 1990); 3) periodic changes in redox conditions at the ocean bottom (Oceanic Red Beds, ORBs) (Wang et al., 2009); and 4) rapid biotic radiations and turnovers (Leckie et al., 2002). The Aptian-Albian time is also of interest for one of the most noteworthy geomagnetic events, namely the post-M0r “Cretaceous Quiet Zone”. This long and constant normal polarity superchron without any convincing true reversal to date (Satolli et al., 2008) precludes usage of reversals magnetostratigraphy from the Aptian through the Santonian. The Poggio le Guaine core was designed to provide a high-resolution age model and a high-resolution relative magnetic paleointensity reference curve for the Aptian-Albian interval of the long normal Cretaceous superchron; it was also designed to understand the causal linkages among geological, biogeochemical, oceanographic and climatic eventsas well as their consequences. The core was drilled at Poggio le Guaine, where the most continuous, complete, and best preserved Aptian-Albian succession is exposed throughout the Umbria-Marche Basin (UMB) of the northern Apennines of central Italy (Fig. 1). It represents a continuous record of fossiliferous pelagic rocks extending from the Albian-Cenomanian boundary down to the uppermost Barremian (99.6–126 Ma). In this progress report we present the first preliminary findings of this ongoing project