Lead in ancient Rome’s city waters Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe ...
Proceedings of the National Academy of Sciences - PNAS,
05/2014, Letnik:
111, Številka:
18
Journal Article
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It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the ...gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system.
River deltas are strongly affected by demographic growth and by the intensification of land use. The migration of deltaic coastlines is often rapid, threatening urban settlements, coastal farming, ...and coastal biotopes. Some deltas benefit from centuries of monitoring, such that the evolution of their coastline is well documented. For most deltas, however, such long records do not exist. The study of their geomorphological evolution can benefit from overlapping maps drafted over time, combined with aerial photographs and satellite images, to track the evolution of fluvial and coastal landforms. Both fluvial and coastal landforms are sensitive to variations in water and sediment supply, such that covariations in the evolution of these landforms, or the lack thereof, provide clues on the contribution of water and sediment supply to delta evolution. We document the evolution of river channels and coastlines in the delta of the Aceh River in northwest Sumatra, by overlying maps, ortho‐rectified aerial photographs, and satellite images covering the past 130 years. We assess the accuracy of the overlays, and then use multivariate statistics to analyze the co‐evolution of fluvial and coastal landforms. We propose that a progressive decrease in sediment supply spurred river channel lengthening and narrowing, landward migration of the shoreline, and narrowing of beach ridges. The 2004 Indian Ocean tsunami generated an instantaneous retreat of the coastline that amounts to ∼53% of the coastal retreat from 1884 to 2019 ce. Post‐tsunami evolution is marked by an irreversible acceleration of previous trends. Beach ridges located up‐drift of rivers and tidal channel mouths are more sensitive to long‐term landward retreat and tsunamigenic erosion.
GIS and multivariate analyses reveal coeval fluvial‐coastal landform changes in the Aceh River delta during the century leading to the 2004 Indian Ocean tsunamin (IOT). Decrease in river‐born sediments led to subsequent retreat of the shoreline until the delta was hit by the 2004‐IOT. The tsunami generated coastal retrogradation that amounts to ∼ 53% of the overall coastal retreat from 1884 to 2019. Therefore, post‐tsunami evolution only stands out as an irreversible acceleration of previous trends, rather than unusual dynamics.
Over the last 20 years, the geoarchaeology of ancient harbours has been a very active area of research around the Mediterranean basin, generating much palaeoenvironmental data from many sites, ...including estimations of sedimentation rates, the height of the ancient sea-level at different dates and palaeo-geographical reconstructions. Combining this information has proved a major challenge. This article proposes a new chart called the Palaeoenvironmental Age-Depth Model (PADM chart), that allows the researchers to combine all relevant indicators in order to estimate harbour potential of a given ancient port, and to generate comparable data between harbours in terms of degree of closure and water depth available against a synchronised chronology. This new approach, developed in the context of the ERC-funded RoMP Portuslimen project, takes into account estimations of water depths relating to differing Roman ship draughts at different periods. It is tested against the palaeoenvironmental evidence published over 10 years from two Roman harbours located at the mouth of the river Tiber: Ostia and Portus. This reveals that: (1) there has been an underestimate of the real sedimentation rates due to the margins of error of the radiocarbon dates; (2) there was effective control of the water column by dredging; (3) there were different periods of control of the sedimentation. We suggest that the navigability of the Ostia harbour by ships with shallower draughts was maintained until sometime between the 2nd c. BC and 1st c. AD, while at Portus it was retained until the 6th-7th c. AD.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•Combining MIRS-XRF and DA to fingerprint the alluvial sources of beach sands.•Optimal source fingerprinting is achieved with the medium sand fraction.•DA predictions show good agreement with simple ...forward modeling of sediment fluxes.•Sand provenances display affinities organized into clusters of coastline stretches.•Sand fossil stocks from former beach ridges contribute to post-tsunami beach recovery.
Determining modern sediment provenance along sandy beaches helps understanding coastline dynamics and can therefore assist coastal management. Provenance analysis relies usually on mineralogical, elemental, and isotopic fingerprinting of sediment sources. Mid-Infrared Spectroscopy (MIRS) offers a rapid and non-destructive alternative. It relies on the identification of molecular-bonds in organic and inorganic materials. Thus far, MIRS has been used to fingerprint fine-grained sediments in mountainous and agricultural catchments. Here we use MIRS to analyze a range of sediment grain sizes (<0.25 mm; 0.25–0.5 mm; 0.5–2 mm) in modern fluvial and coastal sands, located in the delta of the Aceh River in Sumatra. Variations in molecular bond associations are compared to variations in major element concentration, quantified by portable X-ray fluorescence (pXRF) on a subset of samples. Covariations between MIRS and pXRF data are used to predict major element concentrations in all samples. Discriminant Analysis (DA) is used to classify sand-feeding streams into groups possessing distinctive MIRS fingerprints. DA proximity relationships are then used to predict the contribution of each source group to trunk stream sand and beach sands. The best discrimination is obtained among sands belonging to the medium grain-size fraction. Simple forward modeling of the expected contributions of the different sources is used to shade light on the DA-predicted association patterns. It helps discussing the biases introduced by sediment compositional changes from the headwaters to the coast, especially hydrodynamic sorting. We find that sand composition along the delta shoreline is primarily controlled by the asymmetric dispersal of sediment from the Aceh River mouth, owing to directional longshore drift. Local variations are generated by particle-size effects and by the propensity of the coast to erode or thicken over the past century. The coastal stretches the most severely damaged by the 2004 Indian Ocean Tsunami exhibit the greatest variations in apparent provenance between sub-fractions.
Heavy metals from urban runoff preserved in sedimentary deposits record long-term economic and industrial development via the expansion and contraction of a city’s infrastructure. Lead concentrations ...and isotopic compositions measured in the sediments of the harbor of Ostia—Rome’s first harbor—show that lead pipes used in the water supply networks of Rome and Ostia were the only source of radiogenic Pb, which, in geologically young central Italy, is the hallmark of urban pollution. High-resolution geochemical, isotopic, and 14C analyses of a sedimentary core from Ostia harbor have allowed us to date the commissioning of Rome’s lead pipe water distribution system to around the second century BC, considerably later than Rome’s first aqueduct built in the late fourth century BC. Even more significantly, the isotopic record of Pb pollution proves to be an unparalleled proxy for tracking the urban development of ancient Rome over more than a millennium, providing a semiquantitative record of the water system’s initial expansion, its later neglect, probably during the civil wars of the first century BC, and its peaking in extent during the relative stability of the early high Imperial period. This core record fills the gap in the system’s history before the appearance of more detailed literary and inscriptional evidence from the late first century BC onward. It also preserves evidence of the changes in the dynamics of the Tiber River that accompanied the construction of Rome’s artificial port, Portus, during the first and second centuries AD.
This study examines the long‐term interactions between the well‐known Roman city of Ostia and a river meander. Located at the mouth of the Tiber river, Ostia was a major harbor city that connected ...Rome to the Mediterranean Sea. Based on aerial photography and borehole analysis, the paleodynamics of the Fiume Morto's paleomeander are understood to be linked to the urban evolution of the city of Ostia. Four periods of evolution have been identified as a result of this interdisciplinary work: (1) the foundation of Ostia's urban center, in the 4th to 3rd century BC, occurred when the meander already existed; (2) between the 4th century BC and the 3rd century AD, human/environmental interactions contributed to the compound growth of the meander that possibly eroded an important Roman road linking Ostia to Rome; (3) from the Imperial period until the meander was cut off in AD 1557–1562, the constricted meander channel at the apex led to the stability of the downstream river channel; (4) the cutoff of the paleomeander was completed in 1562, leading to the filling of the paleochannel. These successive phases of channel evolution mark changing fluvial risks from the Roman period to today.
Located between the deltaic plain and the subaqueous delta, base level is one of the most important factors that affect depositional elements and the sedimentary architecture of river deltas. In this ...respect, its changes are essential to reconstruct delta evolution during the Holocene. In this paper, we study three cores drilled in the Tiber delta (Italy). Palaeoenvironmental analyses were performed and included new sedimentological data (laser grain size, loss-on-ignition, magnetic susceptibility), new data from bioindicators (ostracods and macrofauna), and 11 new radiocarbon dates. The three cores were analysed and replaced in a cross section between the Inner and Outer Tiber delta, i.e.,in the palaeolagoon and in the progradational delta plain. First, we have mapped the Holocene transgression and progradation of the Ostia area using palaeoenvironmental age-depth modelling techniques (PADMs). PADM charts help to interpret a stratigraphic succession in a river delta. They contribute to the understanding of the links between depositional environments, sedimentation rate, and sea level rise and to reconstruct coastline trajectories. More precisely, they contribute to the interpretation of the consequences of the sea level jumps dated to the 9000–8000 cal. BP period on coastal environments and help to identify progradational phases (around 4 k, and from 2.8 to 2.6 k cal. BP). Second, we identify indirect (freshwater bioindicators) and direct (bedload-derived facies) evidence of fluvial activity in the studied cross section. The studied deep cores indicate that at least one palaeochannel of the Tiber River was already flowing in the middle/southern part of the delta from 4 k cal. BP. Finally, a first map of the lateral mobility of the palaeochannels of the Tiber River is proposed for the last 6 k cal. BP using the new data and a synthesis of all the data available at the scale of the delta.
•Reconstruction of coastal transgression and progradation at the transition between the inner and outer delta plain near Ostia;•High sedimentation rates and deepening facies coeval to sea level jumps from the 9-8 k cal. BP;•Strong progradational phases are recorded around 4k cal. BP, and from 2.8 to 2.6k cal. BP;•Identification of the Tiber River influence below and near the area of the archaeological site of Ostia: 4.2 to 4 k, 2.9 to 2.5 k, and 2.5 to 1.7k cal. BP;•PADM chart demonstrates great efficiency in interpreting stratigraphic successions and coastline-trajectoriesin a river delta.
Economic resilience of Carthage during the Punic Wars Delile, Hugo; Pleuger, Elisa; Blichert-Toft, Janne ...
Proceedings of the National Academy of Sciences - PNAS,
05/2019, Letnik:
116, Številka:
20
Journal Article, Web Resource
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While the Punic Wars (264–146 BC) have been the subject of numerous studies, generally focused on their most sensational aspects (major battles, techniques of warfare, geopolitical strategies, etc.), ...curiously, the exceptional economic resilience of the Carthaginians in the face of successive defeats, loss of mining territory, and the imposition of war reparations has attracted hardly any attention. Here, we address this issue using a newly developed powerful tracer in geoarchaeology, that of Pb isotopes applied to paleopollution. We measured the Pb isotopic compositions of a well-dated suite of eight deep cores taken in the Medjerda delta around the city of Utica. The data provide robust evidence of ancient lead–silver mining in Tunisia and lay out a chronology for its exploitation, which appears to follow the main periods of geopolitical instability at the time: the Greco-Punic Wars (480–307 BC) and the PunicWars (264–146 BC). During the last conflict, the data further suggest that Carthage was still able to pay indemnities and fund armies despite the loss of its traditional silver sources in the Mediterranean. This work shows that the mining of Tunisian metalliferous ores between the second half of the fourth and the beginning of the third century BC contributed to the emergence of Punic coinage and the development of the Carthaginian economy.
Fluvial and coastal landforms are indicative of landscape river delta evolution over time and provide clues for understanding coastal adjustments to sea-level and fluvial dynamics fluctuations, ...tectonic displacements, and extreme waves. We have mapped the surface and sub-surface footprints of fluvial and coastal geomorphological features in the Aceh River delta, northern Sumatra, using imagery dataset, vertical facies logging and helicopter electromagnetic surveys. The result is a geomorphological map at the scale of 1:75.000 which outlines the main features of the deltaic plain, including rivers, tidal and buried channels, fluvial levees, beach ridges, swales, tidal flats and lagoons. We compare their spatial distribution to the geometry of buried sediment bodies, revealed by boreholes and resistivity maps. Buried channel belts and floodplain deposits document the former locations of the distributary channels of the Aceh River. Coastal-parallel beach ridges evidence 7-8 km of asymmetric delta progradation since the mid-Holocene sea-level high stand.
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