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Urban-geomorphology studies in historical cities provide a significant contribution towards the broad definition of the Anthropocene, perhaps even including its consideration as a new unit of geological time. Specific methodological approaches to recognize and map landforms in urban environments, where human-induced geomorphic processes have often overcome the natural ones, are proposed. This paper reports the results from, and comparison of, studies conducted in coastal historical cities facing the core of the Mediterranean Sea – that is, Genoa, Rome, Naples, Palermo (Italy) and Patras (Greece). Their settlements were facilitated by similar climatic and geographical contexts, with high grounds functional for defence, as well as by the availability of rocks useful as construction materials, which were excavated both in opencast and underground quarries. Over centuries, urbanization has also required the levelling of relief, which was performed by the excavation of heights, filling of depressions and by slope terracing. Consequently, highly modified hydrographic networks, whose streams were dammed, diverted, modified in a culvert or simply buried, characterize the selected cities. Their urban growth, which has been driven by maritime commercial activities, has determined anthropogenic coastal progradation through port and defence or waterfront works. Aggradation of artificial ground has also occurred as a consequence of repeated destruction because of both human and natural events, and subsequent reconstruction even over ruins, buried depressions and shallow cavities. As a result, the selected cities represent anthropogenic landscapes that have been predominately shaped by several human-driven processes, sometimes over centuries. Each landform represents the current result, often from multiple activities with opposing geomorphic effects. Beyond academic progress, we believe that detecting and mapping these landforms and processes should be compulsory, even in risk-assessment urban planning, because of the increase of both hazards and vulnerability as a result of climate-change-induced extreme events and extensive urbanization, respectively.

In this paper, we present the results of a detailed geomorphological and sedimentological study of a coastal sector of southern Italy, the Pineta della foce del Garigliano SCI (i.e. Site of Community Importance), which is largely affected by shoreline retreat and the degradation of dune habitat. The analysis of shoreline evolution demonstrates that severe erosion processes have occurred over the last 50 years. They caused the complete dismantling of the foredune, whereas the anomalous and advanced position of the secondary dune promoted a progressive loss of vegetation habitat of high environmental value such as juniper (Juniperus oxycedrus ssp. macrocarpa). Morpho-sedimentary data and hydrodynamic models suggest that the main climate events promoted a net longshore transport toward the South. Our analyses confirm that erosion processes are linked to natural factors but several negative human practices have contributed to the acceleration of shoreline retreat and degradation of the dune habitat. In addition to its scientific value, the map and data here presented represent an important tool for beach management purposes.

A multidisciplinary survey was carried out on the quality of water and sediments of the estuary of the Sele river, an important tributary of the Tyrrhenian Sea, to assess anthropogenic pressures and natural variability. Nine sediment sites were monitored and analyzed for granulometry, morphoscopy, benthic foraminifera and ostracod assemblages, heavy metals, and polycyclic aromatic hydrocarbons. Surface water was assayed for ionic composition and phytoplankton biomass. Total organic carbon (TOC) and total nitrogen (TN) in sediments were higher in the inner part of the estuary (IE), up to 12.7 and 0.7% because of anthropic influence. In waters, N-NH4, N-NO3, and Ptot. were high, with loads of Ptot in IE exceeding ~fourfold the limit. Here, it was also observed that the highest primary production was Chl-a, 95.70 &micro, g/L, with cryptophytes, 37.6%, and diatoms, 33.8%, being the main phytoplanktonic groups. The hierarchical analysis split the estuary into two areas, with marked differences in anthropic pollution. Waters were classified as poor&ndash, bad level with respect to the content of nutrients. Sedimentological assay reveals littoral erosion and poor supply of river sandy sediments. The erosion environment is confirmed by the presence of meiobenthic recent marine forms intrusion inside the river. All these data reveal the fragility of the estuary and the need of urgent remediation actions.

Using morphological, stratigraphic, paleoecological and geoarcheological data, as well as radiocarbon datings, we reconstructed the evolution of the coastal plain of Mondragone, in the northern sector of the Campania Plain, during the last 40 kyr. The Late Pleistocene-Holocene morphodynamics of this coastland were mainly dictated by mutual interaction between tectonics, sea-level fluctuations, Quaternary volcanic eruptions, and subsidence. These processes also influenced the dynamics of prehistoric and proto-historic human populations. Actually, the discovery over the last 25 years of several archaeological sites referable to Upper Paleolithic-Early Iron Age as well as the recent finding of artifacts, fauna and, for the third time in Campania, of Neanderthal human remains in the Roccia San Sebastiano cave, demonstrates that the coastal plain of Mondragone had always hosted human settlements. This constant frequentation is confirmed by, both emerged and submerged, ruins of Roman age and Middle Ages, and the high level of urbanization of the modern town. The interpretation of four borehole stratigraphic sequences down to 22 m bgl, of microfossils analysis and sediment facies highlighted the succession of transition, from marine to freshwater, and continental paleoenvironments in this coastal plain. These wetlands developed in climatic conditions that varied from glacial (Wurm) to postglacial phases. Some deposits are interpreted as marshy sediments accumulated in shallow, elongated ponds behind sandy beach or dunes, which existed almost up to the present. The reconstruction of landscape morphodynamic evolution shows that after the “super eruption” of the Campanian Ignimbrite (∼39 kyr BP) the physiography abruptly changed. A wide gulf characterized by gray tuff cliffs and facing northwest formed, along the littoral between the Garigliano and the Volturno river mouths during the volcanic stasis of the Phlegrean Fields, which lasted about ten thousand years after the violent ignimbrite eruption. In this period, the presence of Neanderthal and of a settlement in the Roccia San Sebastiano cave, at the foot of Mt. Massico, is proven by the findings of an excavation. Later (∼20 kyr BP - Holocene), subsidence and sea-level rise activated strong erosion processes due to the postglacial marine ingression, with a consequent rapid shoreline recession and the genesis of transition environments. Finally, according to the results of previous multidisciplinary research carried out on other Campania coastal plains, adjacent or not to the studied area, distinct generations of post-Campanian Ignimbrite - Holocene coastal lakes (lagoons, ponds) and waterlogged environments (marshes, quagmires) were recognized, slightly below and at the current sea-level.

Most of the literature reports on the impact of the former Bagnoli brownfield on the pollution of Bagnoli Bay, embedded in the Gulf of Pozzuoli (GoP). Thus, we studied concentrations, types and sources of sixteen PAHs (EPA) in sediments at 22 sites along 5 transects covering the entire area of GoP. Outstanding levels of PAHs were found, varying from 7.1 μg g−1 to 2.5 E +3 μg g−1. Sediments collected at sites far away from Bagnoli were found to be polluted to a similar extent than those facing the brownfield site, with values > 100 μg g−1. Total PAHs levels in the sediments of GoP were higher by thirty-eleven thousand fold than those reported by other studies from various marine sites in the world. Transit axes of fine and very fine sands and diagnostic indexes revealed a common pyrolytic PAHs pollution spreading from the Bagnoli plant to all GoP.

The distribution of metals in surface sediments of Gulf of Pozzuoli (GoP), embedding the former second Italian largest integrated steelworks of Bagnoli, was studied based on sediment dispersal, quality guidelines (SQGs) and quantitative pollution indices of the respective metals. As, Cd, Hg, Pb, Zn largely exceeded the limits. Hg had a mean of 5.8 mg/kg, twentyfold higher the rule, accumulating primarily near Bagnoli site. The mean effective range quotient, m-ERM-Q, revealed a high potential for negative biological effects especially in the area nearby the Bagnoli site. The enrichment factor (EF) values were outstandingly high, > 1.5 with values which were often ≥ 100. The geoaccumulation index, Igeo, was very critical for Cr, Cu, Hg and Ni, showing an Igeo in the range of strongly polluted (4 < Igeo < 5) and very strongly polluted (Igeo > 5). The principal component analysis (PCA) and Pearson's correlation matrix (CM), excluded significant contribution from weathering products.