Temporality, cultural biography and seasonality: rethinking time in wetland archaeology

Wetland archaeology is uniquely well placed to investigate questions of chronology, temporality, life-cycles and seasonality. Beyond the usual archaeological approaches to time (eg seriation, typology and stratigraphy), most wetland archaeological investigations have access to a ready supply of samples (ie wood, peat and organic deposits) for absolute scientific dating, particularly radiocarbon and dendrochronology. Indeed, the success of dendrochronology in revealing dynamic sequences of site and regional occupation, use and abandonment are well known. Investigating wetland archaeological sites, environmental archaeologists have used the evidence of insects' plant remains, seeds and even testate amoeba to establish the season, or months, of a site's occupation. Soil micromorphologists have carried out innovative studies of settlement deposits to reconstruct the chronological sequences of processes and events leading to their formation. In brief, wetland archaeology has become adept at calibrating past times.

A wind tunnel model for quantifying fluxes in the urban boundary layer

Transport of pollution and heatout of streets into the boundary layer above is not currently understood and so fluxes cannot be quantified. Scalar concentration within the street is determined by the flux out of it and so quantifying fluxes for turbulent flow over a rough urban surface is essential. We have developed a naphthalene sublimation technique to measure transfer from a two-dimensional street canyon in a wind tunnel for the case of flow perpendicular to the street. The street was coated with naphthalene, which sublimes at room temperature, so that the vapour represented the scalar source. The transfer velocity wT relates the flux out of the canyon to the concentration within it and is shown to be linearly related to windspeed above the street. The dimensionless transfer coefficient wT/U�� represents the ventilation efficiency of the canyon (here, wT is a transfer velocity,U�� is the wind speed at the boundary-layer top). Observed values are between 1.5 and 2.7 ��10-3 and, for the case where H/W���0 (ratio of buildingheight to street width), values are in the same range as estimates of transfer from a flat plate, giving confidence that the technique yields accurate values for street canyon scalar transfer. wT/U�� varies with aspect ratio (H/W), reaching a maximum in the wake interference regime (0.3 < H/W < 0.65). However, when upstream roughness is increased, the maximum in wT/U�� reduces, suggesting that street ventilation is less sensitive to H/W when the flow is in equilibrium with the urban surface. The results suggest that using naphthalene sublimation with wind-tunnel models of urban surfaces can provide a direct measure of area-averaged scalar fluxes.

Sunlit fractions on urban facets: impact of spatial resolution and approach

The extent of the surface area sunlit is critical for radiative energy exchanges and therefore for a wide range of applications that require urban land surface models (ULSM), ranging from human comfort to weather forecasting. Here a computational demanding shadow casting algorithm is used to assess the capability of a simple single-layer urban canopy model, which assumes an infinitely long rotating canyon (ILC), to reproduce sunlit areas on roof and roads over central London. Results indicate that the sunlit roads areas are well-represented but somewhat smaller using an ILC, while sunlit roofs areas are consistently larger, especially for dense urban areas. The largest deviations from real world sunlit areas are found for roofs during mornings and evenings. Indications that sunlit fractions on walls are overestimated using an ILC during mornings and evenings are found. The implications of these errors are dependent on the application targeted. For example, (independent of albedo) ULSMs used in numerical weather prediction applying ILC representation of the urban form will overestimate outgoing shortwave radiation from roofs due to the overestimation of sunlit fraction of the roofs. Complications of deriving height to width ratios from real world data are also discussed.

Examining the relationships between Holocene climate change, hydrology, and human society in Ireland

This thesis explores human-environment interactions during the Mid-Late Holocene in raised bogs in central Ireland. The raised bogs of central Ireland are widely-recognised for their considerable palaeoenvironmental and archaeological resources: research over the past few decades has established the potential for such sites to preserve sensitive records of Holocene climatic variability expressed as changes in bog surface wetness (BSW); meanwhile archaeological investigations over the past century have uncovered hundreds of peatland archaeological features dating from the Neolithic through to the Post-Medieval period including wooden trackways, platforms, and deposits of high-status metalwork. Previous studies have attempted to explore the relationship between records of past environmental change and the occurrence of peatland archaeological sites reaching varying conclusions. More recently, environmentally-deterministic models of human-environment interaction in Irish raised bogs at the regional scale have been explicitly tested leading to the conclusion that there is no relationship between BSW and past human activity. These relationships are examined in more detail on a site-by-site basis in this thesis. To that end, testate amoebae-derived BSW records from nine milled former raised bogs in central Ireland were produced from sites with known and dated archaeological records. Relationships between BSW records and environmental conditions within the study area were explored through both the development of a new central Ireland testate amoebae transfer function and through comparisons between recent BSW records and instrumental weather data. Compilation of BSW records from the nine fossil study sites show evidence both for climate forcing, particularly during 3200-2400 cal BP, as well as considerable inter-site variability. Considerable inter-site variability was also evident in the archaeological records of the same sites. Whilst comparisons between BSW and archaeological records do not show a consistent linear relationship, examination of records on a site-by-site basis were shown to reveal interpretatively important contingent relationships. It is concluded therefore, that future research on human-environment interactions should focus on individual sites and should utilise theoretical approaches from the humanities in order to avoid the twin pitfalls of masking important local patterns of change, and of environmental determinism.

CO2 emission estimation in the urban environment: measurement of the CO2 storage term

Eddy covariance has been used in urban areas to evaluate the net exchange of CO2 between the surface and the atmosphere. Typically, only the vertical flux is measured at a height 2���3 times that of the local roughness elements; however, under conditions of relatively low instability, CO2 may accumulate in the airspace below the measurement height. This can result in inaccurate emissions estimates if the accumulated CO2 drains away or is flushed upwards during thermal expansion of the boundary layer. Some studies apply a single height storage correction; however, this requires the assumption that the response of the CO2 concentration profile to forcing is constant with height. Here a full seasonal cycle (7th June 2012 to 3rd June 2013) of single height CO2 storage data calculated from concentrations measured at 10 Hz by open path gas analyser are compared to a data set calculated from a concurrent switched vertical profile measured (2 Hz, closed path gas analyser) at 10 heights within and above a street canyon in central London. The assumption required for the former storage determination is shown to be invalid. For approximately regular street canyons at least one other measurement is required. Continuous measurements at fewer locations are shown to be preferable to a spatially dense, switched profile, as temporal interpolation is ineffective. The majority of the spectral energy of the CO2 storage time series was found to be between 0.001 and 0.2 Hz (500 and 5 s respectively); however, sampling frequencies of 2 Hz and below still result in significantly lower CO2 storage values. An empirical method of correcting CO2 storage values from under-sampled time series is proposed.

Kerb and urban increment of highly time-resolved trace elements in PM10, PM2.5 and PM1.0 winter aerosol in London during ClearfLo 2012

Ambient concentrations of trace elements with 2 h time resolution were measured in PM10���2.5, PM2.5���1.0 and PM1.0���0.3 size ranges at kerbside, urban background and rural sites in London during winter 2012. Samples were collected using rotating drum impactors (RDIs) and subsequently analysed with synchrotron radiation-induced X-ray fluorescence spectrometry (SR-XRF). Quantification of kerb and urban increments (defined as kerb-to-urban and urban-to-rural concentration ratios, respectively), and assessment of diurnal and weekly variability provided insight into sources governing urban air quality and the effects of urban micro-environments on human exposure. Traffic-related elements yielded the highest kerb increments, with values in the range of 10.4 to 16.6 for SW winds (3.3���6.9 for NE) observed for elements influenced by brake wear (e.g. Cu, Sb, Ba) and 5.7 to 8.2 for SW (2.6���3.0 for NE) for other traffic-related processes (e.g. Cr, Fe, Zn). Kerb increments for these elements were highest in the PM10���2.5 mass fraction, roughly twice that of the PM1.0���0.3 fraction. These elements also showed the highest urban increments (~ 3.0), although no difference was observed between brake wear and other traffic-related elements. All elements influenced by traffic exhibited higher concentrations during morning and evening rush hours, and on weekdays compared to weekends, with the strongest trends observed at the kerbside site, and additionally enhanced by winds coming directly from the road, consistent with street canyon effects. Elements related to mineral dust (e.g. Al, Si, Ca, Sr) showed significant influences from traffic-induced resuspension, as evidenced by moderate kerb (3.4���5.4 for SW, 1.7���2.3 for NE) and urban (~ 2) increments and increased concentrations during peak traffic flow. Elements related to regional transport showed no significant enhancement at kerb or urban sites, with the exception of PM10���2.5 sea salt (factor of up to 2), which may be influenced by traffic-induced resuspension of sea and/or road salt. Heavy-duty vehicles appeared to have a larger effect than passenger vehicles on the concentrations of all elements influenced by resuspension (including sea salt) and wearing processes. Trace element concentrations in London were influenced by both local and regional sources, with coarse and intermediate fractions dominated by traffic-induced resuspension and wearing processes and fine particles influenced by regional transport.

Spatial and temporal variability of the concentration field from localized releases in a regular building array

Spatial and temporal fluctuations in the concentration field from an ensemble of continuous point-source releases in a regular building array are analyzed from data generated by direct numerical simulations. The release is of a passive scalar under conditions of neutral stability. Results are related to the underlying flow structure by contrasting data for an imposed wind direction of 0 deg and 45 deg relative to the buildings. Furthermore, the effects of distance from the source and vicinity to the plume centreline on the spatial and temporal variability are documented. The general picture that emerges is that this particular geometry splits the flow domain into segments (e.g. ���streets��� and ���intersections���) in each of which the air is, to a first approximation, well mixed. Notable exceptions to this general rule include regions close to the source, near the plume edge, and in unobstructed channels when the flow is aligned. In the oblique (45 deg) case the strongly three-dimensional nature of the flow enhances mixing of a scalar within the canopy leading to reduced temporal and spatial concentration fluctuations within the plume core. These fluctuations are in general larger for the parallel flow (0 deg) case, especially so in the long unobstructed channels. Due to the more complex flow structure in the canyon-type streets behind buildings, fluctuations are lower than in the open channels, though still substantially larger than for oblique flow. These results are relevant to the formulation of simple models for dispersion in urban areas and to the quantification of the uncertainties in their predictions.

Formulation of a tropical town energy budget (t-TEB) scheme

This work describes the tropical town energy budget (t-TEB) scheme addressed to simulate the diurnal occurrence of the urban heat island (UHI) as observed in the Metropolitan Area of Rio de Janeiro (MARJ; -22A degrees S; -44A degrees W) in Brazil. Reasoning about the tropical urban climate have guided the scheme implementation, starting from the original equations from Masson (Bound-Lay Meteorol 94:357-397, 2000). The modifications include (a) local scaling approaches for obtaining flux-gradient relationships in the roughness sub-layer, (b) the Monin-Obukhov similarity framework in the inertial sub-layer, (c) increasing aerodynamic conductance toward more unstable conditions, and (d) a modified urban subsurface drainage system to transfer the intercepted rainwater by roofs to the roads. Simulations along 2007 for the MARJ are obtained and compared with the climatology. The t-TEB simulation is consistent with the observations, suggesting that the timing and dynamics of the UHI in tropical cities could vary significantly from the familiar patterns observed in mid-latitude cities-with the peak heat island intensity occurring in the morning than at night. The simulations are suggesting that the thermal phase shift of this tropical diurnal UHI is a response of the surface energy budget to the large amount of solar radiation, intense evapotranspiration, and thermal response of the vegetated surfaces over a very humid soil layer.

Evolution of a rift basin dominated by subaerial deposits: The Guaritas Rift, Early Cambrian, Southern Brazil

Most existing models for the evolution of rift basins predict the development of deep-water depositional systems during the stage of greatest tectonic subsidence, when accommodation generation potentially outpaces sedimentation. Despite this, some rift basins do not present deep-water systems, instead being dominated by subaerial deposits. This paper focuses on one of these particular rift basins, the Cambrian Guaritas Rift, Southern Brazil, characterized by more than 1500 m of alluvial and aeolian strata deposited in a 50-km-wide basin. The deposits of the Guaritas Rift can be ascribed to four depositional systems: basin-border alluvial fans, bedload-dominated ephemeral rivers, mixed-load ephemeral rivers and aeolian dune fields. These four systems are in part coeval and in part succeed each other, forming three stages of basin evolution: (i) Rift Initiation to Early Rift Climax stage, (ii) Mid to Late Rift Climax stage, and (iii) Early Post-Rift stage. The first stage comprises most of the Guaritas Group and is characterized by homogeneous bed-load-dominated river deposits, which do not clearly record the evolution of subsidence rates. The onset of sedimentation of finer-grained deposits occurred as a consequence of a reactivation event that changed the outline of the basin and the distribution of the nearby highlands. This strongly suggests that the capture of the main river system to another depression decreased the sediment supply to the basin. The study of the Guaritas Rift indicates that rift basins in which the sediment supply exceeds the accommodation generation occur as a consequence of moderate subsidence combined with the capture of a major river system to the basin during the initial stages of basin evolution. In these basins, changes in the average discharge of the river system or tectonic modification of the drainage network may be the major control on the stratigraphic architecture. (c) 2009 Published by Elsevier B.V.

Tectono-sedimentary evolution of the Neoproterozoic BIF-bearing Jacadigo Group, SW-Brazil

The Jacadigo Group contains one of the largest sedimentary iron and associated manganese deposits of the Neoproterozoic. Despite its great relevance, no detailed sedimentological study concerning the unit has been carried out to date. Here we present detailed sedimentological data and interpretation on depositional systems, system tracts, external controls on basin evolution, basin configuration and regional tectonic setting of the Jacadigo Basin. Six depositional systems were recognized: (I) an alluvial fan system; (II) a siliciclastic lacustrine system; (III) a fan-delta system; (IV) a bedload-dominated river system; (V) an iron formation-dominated lacustrine or marine gulf system; and (VI) a rimmed carbonate platform system. The interpreted depositional systems are related to three tectonic system tracts. The first four depositional systems are mainly made of continental siliciclastics and refer to the rift initiation to early rift climax stage; the lake/gulf system corresponds to the mid to late rift climax stage and the carbonate platform represents the immediate to late post rift stage (Bocaina Formation deposits of the Ediacaran fossil-bearing Corumba Group). The spatial distribution of the depositional systems and associated paleocurrent patterns indicate a WNW-ESE orientation of the master fault zone related to the formation of the Jacadigo Basin. Thus, the iron formations of the Jacadigo Group were deposited in a starved waterbody related to maximum fault displacement and accommodation rates in a restricted continental rift basin. The Fe-Si-Mn source was probably related to hydrothermal plume activity that reached the basin through the fault system during maximum fault displacement phases. Our results also suggest a restricted tectono-sedimentary setting for the type section of the Puga Formation. The Jacadigo Group and the Puga Formation, usually interpreted as glacial deposits, are readdressed here as basin margin gravitational deposits with no necessary relation to glacial processes. (C) 2011 Elsevier B.V. All rights reserved.

Determina����o de propriedades f��sicas de diferentes materiais para discos e pastilhas de freio e rela����o destas propriedades com ru��do

Este trabalho visou a determina����o experimental de propriedades f��sicas b��sicas de materiais para pastilhas e discos de freio de diferentes composi����es qu��micas. Posteriormente, estas propriedades foram correlacionadas com resultados de avalia����o de ru��do de freio dos respectivos materiais. As propriedades f��sicas determinadas para os materiais de pastilhas de freio foram: dureza, densidade, porosidade, compressibilidade a frio, compressibilidade a quente, transmiss��o t��rmica, resist��ncia �� compress��o, resist��ncia �� tra����o, resist��ncia interna ao cisalhamento, m��dulo de elasticidade, freq����ncias de resson��ncia, ��ndice de amortecimento, coeficiente de atrito em diferentes condi����es de frenagem, e taxas de desgaste. Medi����es incluem verifica����es do efeito do aumento da temperatura na varia����o de algumas das propriedades citadas. A avalia����o de ru��do de freio gerado com uso das diferentes composi����es de materiais foi realizada atrav��s do uso de um sistema de freio padr��o, e o ensaio executado em um dinam��metro tipo inercial dotado de recursos como c��mara para isolamento ac��stico de ru��do externo e sistema de aquisi����o de sinais para monitoramento dos par��metros de frenagem: tempo, torque, press��o, temperatura e espectro de ru��do gerado em escala de tempo e freq����ncia. Os materiais de pastilhas de freios inclu��dos nesta verifica����o experimental foram selecionados de seis aplica����es bastante distintas, como por exemplo: materiais para pastilhas de freio traseiro de ve��culos de passeio, pastilhas para freio dianteiro de ve��culos de passeio, pastilhas para caminhonetes, pastilhas para caminh��es leves e micro��nibus Al��m da composi����o qu��mica bastante distinta, estudos da influ��ncia da altera����o de par��metros de processo de fabrica����o nas propriedades f��sicas do material de atrito foram considerados. Para a avalia����o do efeito da varia����o de composi����o de materiais de discos de freio na gera����o de ru��do, cinco diferentes tipos de discos foram selecionados. Dentre estas vers��es est��o inclu��das: a liga de ferro fundido cinzento do material tipo original do sistema de freio a disco padr��o, uma vers��o de ferro fundido cinzento de baixo custo comprada no mercado de autope��as de reposi����o, um ferro fundido cinzento com alto de teor de carbono, um ferro fundido cinzento com adi����o de tit��nio como elemento de liga, e, finalmente, um ferro fundido vermicular. Propriedades f��sicas dos materiais de discos de freio n��o foram t��o amplamente avaliadas como no caso dos materiais de pastilhas, mesmo assim dados de dureza, densidade, resist��ncia �� tra����o, ��ndice de amortecimento e freq����ncias fundamentais de resson��ncia foram determinados para os diferentes materiais.Ao final do trabalho, foram definidas correla����es entre ru��do de freio e propriedades f��sicas dos materiais de pastilhas de freio que indicam que o material de atrito da pastilha �� mais propenso a apresentar ru��do quando: menos poroso, com maior resist��ncia mec��nica, maior m��dulo de elasticidade, maior dureza (valores mais baixos de dureza Gogan), e maior coeficiente de atrito. Tamb��m foram detectadas altera����es significativas no comportamento de ru��do com uso de diferentes materiais de discos de freio, mas n��o foram estabelecidas correla����es conclusivas entre as propriedades dos discos de freio e sua propens��o a ru��do devido ao baixo n��mero de vers��es avaliadas.

Caracteriza����o biol��gica e molecular da intera����o de Drechslera avenae (Eidam) Sharif com cultivares e linhagens de aveia (Avena sativa L.)

A helmintosporiose, incitada por Drechslera avenae (teleomorfo, Pyrenophora avenae), constitui fator limitante �� produ����o e �� qualidade do gr��o de aveia (Avena sativa L). A caracteriza����o biol��gica e molecular da intera����o aveia - D. avenae pode contribuir para o manejo e a determina����o de estrat��gias de controle da doen��a. Para a caracteriza����o biol��gica, foram avaliadas trinta cultivares de aveia quanto �� percentagem de ��rea foliar com sintomas da doen��a e o tipo de les��o, inicialmente sob condi����es de inocula����o artificial com tr��s isolados do fungo e, ap��s, no campo, sob condi����es naturais de infec����o. Os resultados demonstraram haver intera����es significativas entre os gen��tipos da planta e isolados do pat��geno. Classificaram-se como mais resistentes ao fungo OR 4, UFRGS 7, UFRGS 14, UFRGS 18 e UPF 19. Para a caracteriza����o molecular da intera����o, cinco gen��tipos (CTC 5, ORLA 975, preta-comum, UFRGS 18 e UPF 17), n��o inoculados e inoculados com dois isolados do fungo, foram investigados para a an��lise de express��o diferencial de genes ap��s 12, 24 e 72 horas ap��s a inocula����o. A partir do RNA total extra��do das plantas submetidas aos tratamentos, realizaram-se a s��ntese de cDNA (RT-PCR), o isolamento de cDNAs expressados diferencialmente e a produ����o de sondas para a verifica����o de mRNAs induzidos, os quais foram hibridizados por meio de ���Southern blot��� e ���Reverse Northern���. Foram observadas diferen��as na express��o de genes, em n��vel de mRNA, entre plantas sadias e infectadas, tendo-se obtido sete fragmentos de cDNAs relacionados �� intera����o com D. avenae, os quais foram comparados quanto a sua similaridade com seq����ncias depositadas no banco de dados do Genbank. Pela an��lise de ���Reverse Northern���, p��de-se identificar um cDNA denominado E3-IFCO, relacionado com a resposta de defesa da planta.

Afastamentos composicionais no Choro Torturado de Camargo Guarnieri

O presente trabalho consiste em examinar a presen��a dos elementos caracter��sticos do choro tradicional nos ��mbitos mel��dico, harm��nico, r��tmico e formal no Choo Torturado de Camargo Guarnieri buscando investigar os afastamentos composicionais em rela����o ao paradigma da defini����o de choro vigente em sua ��poca. Estes afastamentos est��o fundamentados basicamente no conceito de Pantonalidade estabelecido por Rudolph Reti em Tonality, Atonality, Pantonality ��� A sudy of some trends inTwentieth Century Music (1958).

Sitios geologicos e geomorfologicos dos municipios de Acari, Carna��ba dos Dantas e Currais Novos, regi��o sarid�� do Rio Grande do Norte

Geological and Geomorphological Sites of the Towns of Acari, Carna��ba dos Dantas and Currais Novos, Serid�� Region of the Rio Grande do Norte, northeastern Brazil, consist s of a study about geological, geomorphological, mineralogical, palaeontological and archaeological features of the study area, aiming the identification of sites that presents scientific, historical, cultural, economic and ecological excellent importance, and that they deserve to receive special protection for its maintenance for the gifts and future generations. It was developed according with methods adopted for the Brazilian Commitee of Geological and Paleontological Sites SIGEP/UNESCO and by Initiati ve of Sofia for the Preservation of the Mineral Diversity of the Planet, objectifying the description of the main sites, the its environmental problematic and proposal of protectionistic measures. Seven sites with features and typical structures had been identified that they deserve to be aim of protection. In the Acari town, three sites had been identified: geological -geomorphologicalarchaeological site Barra of the Carna��ba; geological-geomorphological site of the Gargalheiras; and geological-geomorphological site Bico of Arara. In Carna��ba of the Dantas, the geomorphological complex river of the Bojo that possesss canyons and deep throats, with rocky-arts registers of the three great rocky-arts traditions of northeast: Northeast Serid�� Sub-tradition, Wasteland and Itaquatiara. In the Currais Novos town, 3 sites had been also identified: geomorphological site Canyon of the Apertados; geomorphological-archaeological-palaeontological complex of the Totor��; e, geologicalmineralogical site Breju��. Because to the environmental problematic that it involves each one of the identified sites, it is proposed, as a guarantee of protection to these sites, its economic exploitation with the ecogeotouristic activity, that it aims at to the integration of the community in programs of environmental education and others, besides providing to the generation of job and income for the towns. Finally, a series of measures is suggested that they aim at to the efectivation of the activity and to the protection of the sites that they can be classified as natural heritage, in accordance with the denomination of UNESCO, in its program World Natural Heritage

Caracteriza����o e an��lise do talude continental adjacente �� bacia potiguar, NE Brasil

This work presents the results of the first imaging of continental slope adjacent to Potiguar Basin, in the equatorial Brazilian margin (NE Brazil). Swath bathymetry provided a complete coverage of seafloor between the upper and middle slope (100-1,300 m). Fifteen submarine canyons were mapped. The shape of the slope reflects in distinct spatial distribution of the canyons. The western area displays convex profiles which implied a greater amount of incisions by canyons. Some of them have gradient walls higher than 35��. They were classified according to location and morphology. The canyons with heads indenting shelf edge, association with a incised valley and a large fluvial system, high sinuosities, V shape, terraces along margins, further erosive features such as landslide and gullies allow to deduce a sandy-gravelly sedimentation. These canyons are associated with deposition of submarine fan systems that have been considered permeable hydrocarbon reservoirs. The presence of gullies, furrows and dunes demonstrates the role of bottom currents in the shaping of the slope. The enlargement of canyons and the change in the course when they cross the border fault imply that tectonic has also influenced in the morphology of deep waters environments of Potiguar Basin. The current sedimentation of continental slope is considered mixed because the sediments are composed of siliciclastics and bioclasts. Predominant siliciclastics are calcite, dolomite, quartz, and clay minerals. The presence of stable minerals (zircon, tourmaline and rutile), and fragmented bioclasts implies the contributions of Rivers A��u and Apodi