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dynamics of a rotating colony and trajectory of cells

In the southwestern coast of Sardinia coastal sediments preserve evidence of geomorphic processes such as slope, colluviation and pedogenesis, as well as human activities. We present the preliminary results of an integrated approach focused on descriptive and analytical soil investigation together with micromorphological data, geoarchaeological investigations and landscape survey as part of a larger project aimed to characterise the geoheritage of the region. We describe palaeosol sequences related to stratal architectures that date back to the Late Pleistocene. Our goal is to gain information on landscape evolution in the area and the effect of human agency on the larger environment, as well as document hydroclimatic change.At the current coastline level, the last marine transgression exposed marine sequences dated to the MIS5, later covered by fluvial and slope deposits throughout the last portion of the Late Quaternary. Several soil sequences show traces of recent colluvial events of anthropogenic origin. Such deposits contain pottery and other human made materials related to the Iron/roman age. These initial findings seem to suggest a strong control of human activity on environmental change in the area, not related to a single location but widespread in the landscape. This control was such to cover and take precedence over the natural pre-existing surface dynamics, thereby complicating the definition of Anthropocene in Sardinia. Further investigations would bring more light on the ways palaeosols can inform on the shifts in human land use and occupation. How has land use accelerated since the Bronze age? How can these palaeosequences inform us about anthropogenic processes overstepping natural ongoing surface dynamics?

The geological substrate and its landforms, as main providers of natural resources, have a clear influence on landscape management practices The landscape evolution of the island of Sardinia (Italy) during the Holocene has strongly influenced the populations settled there, especially during the Bronze Age. We constructed a map of the land units in the southwestern corner of Sardinia and compared them with the distribution of known Bronze Age megalithic towers called nuraghes. Our aim is to understand which factors represent relevant criteria for settlement and try to infer possible causes.The vast majority of nuraghes are located in proximity to river networks at low and mid elevations. Most densely settled areas also show the highest landscape diversity with a variety of land units much higher than the rest of the territory. Another potential factor affecting the location choice for nuraghes is the presence of elevated outcrops, which provide the advantage of a raised position and of stable foundations. The interaction of human dispersal patterns with landscape features can provide useful information on the sustenance strategies of past communities. It can therefore be interesting to consider the combined effect of geodiversity and landscape diversity in order to build more accurate dispersal models.

This publication is part of the proceedings of the Biot-Bažant Conference on Engineering Mechanics and Physics of Porous Materials, which took place virtually on June 1-3, 2021. It contains a one-page abstract and the video of the talk that was given at the conference.

The work aims to present the first results of the excavation conducted at the Terramara of Pragatto and illustrate the related research project. The area under investigation encompassed a wide strip of about 7,000 square meters corresponding to the southern portion of the settlement. The explorations, conducted by the Archeosistemi AR/S Cooperative, began in May 2016 and are currently being finalized. Excavation reached the settlement’s limits toward both east and west. In the western area, the archaeological stratigraphy resulted progressively decreasing and the presence of a natural slope suggested the existence, already in the Bronze Age, of a watercourse coinciding with the present-day Rio Carpineta. A more complex and articulated system of perimetric delimitation was instead defined in the eastern side, which included a moat, the edges of the embankment’s colluvium, and traces of a palisade and wooden gabions towards the inhabited area. Both structures, the palisade and the gabions, present a gap in correspondence with what could be interpreted as one of the accesses to the village and, although preserved only at the basal level, they appear strictly comparable with those discovered by Pigorini at Castione Marchesi. For what concerns the stratigraphy of the settlement, the materials collected on the surface after that agricultural works have removed the upper levels of the archaeological deposit, date the last occupation to the recent phases of the Bronze Age. The underneath deposit is fully preserved starting from levels dating to the Middle Bronze Age 3 – early Late Bronze Age and it has two distinct phases of well-characterized and regularly spaced heaped dumps. The basal level revealed the existence of a first settlement phase which, in the explored area, seems having included no dwellings, while long palisades delimitating empty areas, as well as holes and stumps, have instead been found. In parallel with the beginning of the excavations, a team was set up to address the research questions related to the geoarchaeological, palaeobotanical, palynological, and zooarchaeological data, as well as to explore potential analyses of metals, objects in animal hard tissues, and macro-lithic tools. The constitution of this team aimed not only at conducting laboratory analyses but also at supporting archaeologists during field investigations. Therefore, in addition to defining proactive protocols for the correct sampling and treatment of artifacts and samples, targeted interventions have been carried out during excavations in response of specific needs emerged during the progress of exploration.

Environmental and time-scale reconstructions of deep sedimentary sequences are based on a wide variety of markers to highlight and characterise environmental variations within a homogeneous sedimentary setting. Moreover, in the lack of reliable age constrain, it is often the only way to highlight timelines and correlations between sequences collected in different places. Within this set of potential markers, palaeosols developed on terrestrial sedimentary beds during biostasy conditions stand out. These evidences are often useful for both their visibility within a core and their strong environmental implications. In continental basins characterized by glacial contributions, they also represent potential time information linked to the fluctuation of glacial and interglacial periods. However, the interpretation of sedimentary markers in cores using visual identification to the naked eye can possibly lead to the wrong conclusions: this method for palaeosol identification is not straightforward and prone to the production of false positives. We conducted detailed micromorphological investigations on a series of markers in a core from the central-northern portion of the Po Plain foreland basin, proximal to the Southern Italian Alps which fed the basin during the Pleistocene.Seventeen sedimentary anomalies were identified during the visual description on the basis of colours and textures as potential palaeosols and were sampled to be studied in thin section. The study allowed to recognise evidences of soil-forming processes, which could characterise the past pedogenesis as well as their environment. From micromorphological analysis, only 4 samples showed visible signs of pedogenesis or post depositional weathering caused by proximity to the surface. Observed elements range from pedoplasmation to pedogenetic features related to redoximorphic processes and clay illuviation, thus allowing to interpreted them as truncated palaeosols. Conversely, 6 samples showed forms of transport of soil material, either sedimentary or in solution, but did not represent soils formed in situ; these can be interpreted as pedorelicts. Of the remaining samples, 5 were calcrete potentially related to groundwaters, and 2 represented accumulations of Fe/Mn oxides in wetland conditions (“bog iron”). These results suggest a reconsideration of the role of palaeosols as stratigraphic markers in the study of subsurface sedimentary sequences. Precise identification and microstructure characterization are necessary to avoid possible misinterpretations and correlations among cores.

In a world where the interaction between humans and the physical landscape is deep and widespread since prehistory, geological and cultural heritage are still very much separate and addressed by experts and professionals coming from very different fields. The scarcity of effective communication channels impairs shared experience and fruitful collaboration in enhancing geosite awareness in the general public. When integrated approaches appear, they often still concentrate on the cultural narration using geological and environmental information only to support a palimpsest very much human-centred. Attention on integrated divulgation of the geological and natural processes surrounding cultural sites is still lacking. In fact, there is the possibility of walking the opposite path: that is, of using cultural heritage in order to inform the public and divulgate past and current geological processes acting on the wider landscape. This is especially true in highly dynamic environments, where geomorphological processes visibly modify cultural landmarks over time. In this sense, coasts are the ideal setting. They have represented one of the preferential places for human settlement since the dawn of civilization. Coastal environments show strong, complex geomorphological dynamics subject to cycles and variations over time which can be recorded in many different archives, some readily understandable by non-experts.In this contribution we bring examples of how the interaction between cultural heritage and geoheritage can be used to enhance the communication of geomorphological issues. The coastal area of the southwestern portion of Sardinia (Italy) is the location of numerous archaeological settlements, ranging from Mesolithic shelters to wide, majestic Punic and Roman trade ports and cities. Sea level rise since the Last Glacial Maximum has widely interested this territory, and its effect is very well recorded in archaeological contexts. Here, variations in topography and geomorphology are changing the contexts of the sites themselves and sometimes threat their integrity through different geological and geomorphological hazards. The development of narrations focused on explaining these processes, using the archaeological evidence as a tool to convey geological concepts, might raise geological awareness in the general public and spread knowledge about the geomorphological history and features of the local and global landscape.

We study the implications of state dependent costs of policy mismatch in political agency models where politicians have reputational concerns and ``good'' politicians share the same objectives with the voters. We find that state-dependent costs can increase the set of parameters where pandering is an equilibrium strategy. Indeed, in our model, pandering can arise even without office rents. Moreover, we show that voters do not necessarily prefer biased politicians to be in favour of the policy that produces the cheapest expected cost of mismatch. We discuss the implications of those results for populism, environmental policies and the equilibrium incentives to over- or under-provide lockdowns or other mitigation measures.