Bronze age landscape degradation in the Northern Argolid: a micromorphological investigation of anthropogenic erosion in the environs of Mycenae, Greece

In this dissertation, I examine the relationship between environmental conditions and human activity in the landscape of the Argive Plain of Greece after the collapse of the Bronze Age palatial system (1200–750 B.C.). I use evidence from four locales: the Petsas House and the Lower Town at Mycenae, to the immediate northwest and southwest of the citadel respectively; the settlement at Chania, three kilometers downstream; and the Northwest Town of Tiryns, in the lower reaches of the plain. I apply micromorphological analysis (the microscopic analysis of soils and sediments) integrated with analysis of grain-size and soil chemistry (assessed by X-Ray Fluorescence and Fourier Transform Infrared) in order to place depositional events within the context of settlement change at the end of the Bronze Age. The climate had been drying during the Late Bronze. An earthquake ca. 1200 B.C. is concurrent with the beginning of the final period of occupation on the edge of the plain around Mycenae. Some accumulation of sandy muds, destabilized sediments from the largely abandoned citadel, is observed at Petsas House as well as in the Lower Town where, additionally, remains were buried by two deposits of red muddy gravels from uncultivated mountain slopes. The gravels are separated by a brief period of stability (less than a century) marked by a weak soil formation, and reached final equilibrium in the Early to Middle Geometric period (900–760 B.C.). At the same time, three kilometers downstream, similar red muddy gravels resulted in the interruption of activity at the settlement of Chania. Meanwhile, at Tiryns, 30 cm of sandy muds, also destabilized by drier conditions, were deposited over decaying mudbrick, implying that the site was already abandoned before sedimentation occurred. The burial of both Mycenae and Tiryns demonstrates the instability in the Argive landscape and the complications of relating these changes to settlement. In the environs of Mycenae, the sudden deposition of muddy gravels certainly brought about the abandonment at Chania, and possibly also in the Lower Town; while at Tiryns abandonment preceded accumulation. This study demonstrates how intensive geoarchaeological study must be a component in properly situating sites in their particular landscapes

Multiplatform-SfM and TLS Data Fusion for Monitoring Agricultural Terraces in Complex Topographic and Landcover Conditions

Agricultural terraced landscapes, which are important historical heritage sites (e.g., UNESCO or Globally Important Agricultural Heritage Systems (GIAHS) sites) are under threat from increased soil degradation due to climate change and land abandonment. Remote sensing can assist in the assessment and monitoring of such cultural ecosystem services. However, due to the limitations imposed by rugged topography and the occurrence of vegetation, the application of a single high-resolution topography (HRT) technique is challenging in these particular agricultural environments. Therefore, data fusion of HRT techniques (terrestrial laser scanning (TLS) and aerial/terrestrial structure from motion (SfM)) was tested for the first time in this context (terraces), to the best of our knowledge, to overcome specific detection problems such as the complex topographic and landcover conditions of the terrace systems. SfM–TLS data fusion methodology was trialed in order to produce very high-resolution digital terrain models (DTMs) of two agricultural terrace areas, both characterized by the presence of vegetation that covers parts of the subvertical surfaces, complex morphology, and inaccessible areas. In the unreachable areas, it was necessary to find effective solutions to carry out HRT surveys; therefore, we tested the direct georeferencing (DG) method, exploiting onboard multifrequency GNSS receivers for unmanned aerial vehicles (UAVs) and postprocessing kinematic (PPK) data. The results showed that the fusion of data based on different methods and acquisition platforms is required to obtain accurate DTMs that reflect the real surface roughness of terrace systems without gaps in data. Moreover, in inaccessible or hazardous terrains, a combination of direct and indirect georeferencing was a useful solution to reduce the substantial inconvenience and cost of ground control point (GCP) placement. We show that in order to obtain a precise data fusion in these complex conditions, it is essential to utilize a complete and specific workflow. This workflow must incorporate all data merging issues and landcover condition problems, encompassing the survey planning step, the coregistration process, and the error analysis of the outputs. The high-resolution DTMs realized can provide a starting point for land degradation process assessment of these agriculture environments and supplies useful information to stakeholders for better management and protection of such important heritage landscapes

Volume estimation of soil stored in agricultural terrace systems : a geomorphometric approach

High-resolution topographic (HRT) techniques allow the mapping and characterization of geomorphological features with wide-ranging perspectives at multiple scales. We can exploit geomorphometric information in the study of the most extensive and common landforms that humans have ever produced: agricultural terraces. We can only develop an understanding of these historical landform through in-depth knowledge of their origin, evolution and current state in the landscape. These factors can ultimately assist in the future preservation of such landforms in a world increasingly affected by anthropogenic activities. From HRT surveys, it is possible to produce high-resolution Digital Terrain Models (DTMs) from which important geomorphometric parameters such as topographic curvature, to identify terrace edges can be extracted, even if abandoned or covered by uncontrolled vegetation. By using riser bases as well as terrace edges (riser tops) and through the computation of minimum curvature, it is possible to obtain environmentally useful information on these agricultural systems such as terrace soil thickness and volumes. The quantification of terrace volumes can provide new benchmarks for soil erosion models, new perspectives to stakeholders for terrace management in terms of natural hazard and offer a measure of the effect of these agricultural systems on soil organic carbon sequestration. This paper presents the realization and testing of an innovative and rapid methodological workflow to estimate the anthropogenic reworked and moved soil of terrace systems in different landscapes. We start with remote terrace mapping at large scale and then utilize more detailed HRT surveys to extract geomorphological features, from which the original theoretical slope-surface of terrace systems were derived. These last elements were compared with sub-surface information obtained from the excavations across the study sites that confirm the reliability of the methodology used. The results of this work have produced accurate DTMs of Difference (DoD) for three terrace sites in central Europe in Italy and Belgium. Differences between actual and theoretical terraces from DTM and excavation evidence have been used to estimate the soil volumes and masses used to remould slopes. The utilization of terrace and lynchet volumetric data, enriched by geomorphometric analysis through indices such as sediment conductivity provides a unique and efficient methodology for the greater understanding of these globally important landforms, in a period of increasing land pressure

Ending the Cinderella Status of Terraces and Lynchets in Europe : The Geomorphology of Agricultural Terraces and Implications for Ecosystem Services and Climate Adaptation

Terraces and lynchets are ubiquitous worldwide and can provide increasingly important Ecosystem Services (ESs), which may be able to mitigate aspects of climate change. They are also a major cause of non-linearity between climate and erosion rates in agricultural systems as noted from alluvial and colluvial studies. New research in the ‘critical zone’ has shown that we must now treat soil production as an ecologically sensitive variable with implications for soil carbon sequestration. In this review and synthesis paper we present a modified classification of agricultural terraces, review the theoretical background of both terraces and lynchets, and show how new techniques are transforming the study of these widespread and often ancient anthropogenic landforms. The problems of dating terraces and the time-consuming nature of costly surveys has held back the geomorphological and geoarchaeological study of terraces until now. The suite of techniques now available, and reviewed here,includes Digital Elevation Models (DEMs) - Structure from Motion (SfM) photogrammetry, Airborne and Terrestrial Laser Scanning (ALS-TLS); optically stimulated luminescence (OSL and pOSL), portable x-ray fluorescence (pXRF), Fourier-transform infra-red analysis (FTIR), phytoliths from plants, and potentially environmental DNA. Three process-related geomorphological questions arise from using this suite of methods; a) can they provide both a chronology of formation and use history, b) can we identify the sources of all the soil components? c) can terrace soil formation and ecosystem services be modelled at the slope to catchment scale? The answers to these questions can also inform the management of the large areas of abandoned and under-used terraces that are resulting from both the economics of farming and rural population changes. Where possible, examples are drawn from a recently started ERC project (TerrACE; ERC-2018-2023; https://www.terrace.no/) that is working at over 15 sites in Europe ranging from Norway to Greece

Early to Middle Bronze Age agricultural terraces in north-east England : morphology, dating and cultural implications

Terracing is found widely in the Mediterranean and in other hilly and mountainous regions of the world. Yet while archaeological attention to these ‘mundane' landscape features has grown, they remain understudied, particularly in Northern Europe. Here, the authors present a multidisciplinary study of terraces in the Breamish Valley, Northumberland. The results date their construction to the Early to Middle Bronze Age, when they were built by cutting back the hillside, stone clearance and wall construction. Environmental evidence points to their use for cereal cultivation. The authors suggest that the construction and use of these terraces formed part of an Early to Middle Bronze Age agricultural intensification, which may have been both demographically and culturally driven

New data from old bones: A taphonomic reassessment of Early Iron Age beef ranching at Nichoria, Greece

This paper evaluates the evidence for post-depositional attrition from faunal material and sediments from Nichoria in Southwest Greece excavated over 40 years ago. Initial publication concluded that a relative increase in cattle in the Early Iron Age settlement indicated a shift to beef ranching. Without access to original archaeological contexts, geoarchaeological analyses were conducted on intact aggregates of sediment from unwashed bags of bone. The results reveal that material underwent differential attrition, likely related to depth from surface, that affected the composition of chronologically sensitive assemblages. The increased presence of cattle in the Early Iron Age is, therefore, more likely related to differential preservation. Well-preserved Early Iron Age assemblages do not show an increased presence in cattle, and similar mortality profiles between the Late Bronze Age and Early Iron Age suggest animal management strategies remained broadly similar. These analyses demonstrate the potential for applying modern taphonomic analyses to older collections

European agricultural terraces and lynchets: from archaeological theory to heritage management

Terraces are highly productive, culturally distinctive socioecological systems. Although they form part of time/place-specific debates, terraces per se have been neglected–fields on slopes or landscape elements. We argue that this is due to mapping and dating problems, and lack of artefacts/ecofacts. However, new techniques can overcome some of these constraints, allowing us to re-engage with theoretical debates around agricultural intensification. Starting from neo-Broserupian propositions, we can engage with the sociopolitical and environmental aspects of terrace emergence, maintenance and abandonment. Non-reductionist avenues include identifying and dating different phases of development within single terrace systems, identifying a full crop-range, and other activities not generally associated with terraces (e.g. metallurgy). The proposition here is that terraces are a multi-facetted investment that includes both intensification and diversification and can occur under a range of social conditions but which constitutes a response to demographic pressure in the face to fluctuating environmental conditions.</p

Chapter 6 - SfM photogrammetry for GeoArchaeology

Geoarchaeological studies have benefits from new technological developments in remote-sensing technologies that have become an integral and important part of the archeological researches. In particular, structure-from-motion (SfM) photogrammetry is one of the most successful emerging techniques in high-resolution topography (HRT) and provides exceptionally fast, low-cost, and easy three-dimensional (3D) survey for geoscience applications. In this chapter, we present an example of SfM application for geoarchaeology. The purpose is to realize HRT digital terrain models (DTMs) of an area of prehistoric agricultural terracing together with a geoarchaeological excavation trench in the Ingram Valley, Northumberland National Park, NE England. The study area is one of the six pilot case studies of TerrACE archeological research project (ERC-2017-ADG: 787790, 2018–2023; https://www.terrace.no/), a 5-year European Research Council grant funded by the European Union. An integrated approach utilizing ground-based and UAV (nadir and oblique) images was used to preserve fine-grained topographic detail and permit the accurate survey of highly vegetated areas and steep or subvertical surfaces (e.g., vertical walls of terraces), while also allowing for the capture of large spatial datasets. The SfM-DTM provided an accurate and high level of detail of the terrace landscape, the archeological features, and the soil and sediment stratigraphy along the excavation trench. An additional terrace was identified that had not been recognized before due to the HRT study bringing out a level of detail that had not been previously observable in this area. The SfM 3D outputs allowed the extraction of profiles, sections, scaled plans, and orthomosaics of the terrace complex and the excavation trench, simplifying and speeding the archeologist's field and laboratory work. SfM has shown it to be a rapid, cost effective, and highly accurate technique for surveying archeological sites at both a landscape and localized scale and adding new and more accurate information in nationally important landscapes and beyond

Academic achievement and smoking initiation in adolescence : a general growth mixture analysis

Aims This study aims to: (i) explore the relations between smoking initiation and different profiles of academic achievement trajectories in early to mid-adolescence; and (ii) to investigate whether background characteristics (gender, ethnicity, grade repetition, parental education) and proximal processes (parental practices, extra-curricular involvement) predicted class membership and smoking initiation. Design Four-year longitudinal cohort study (7th-10th grade). Setting Adolescents completed the questionnaires during school hours. Participants At total of 741 adolescents with no history of smoking in grade 7 participating in the Montreal Adolescent Depression Development Project. Measurements Self-report questionnaires were used to assess predictors and previous smoking in year 1, and smoking initiation by the end of the study. Grade point average (GPA) was obtained twice yearly from school records. Findings Three academic achievement trajectories were identified and found to differ significantly in rates of smoking initiation: persistently high achievers (7.1% smoking), average achievers (15.1% smokers) and unstable low achievers (49.1% smoking). Further, results showed that general parenting practices and parental education indirectly reduced the likelihood of smoking by reducing the risk of membership in classes with lower GPA. Conclusions Adolescents who do well in school are less likely to smoke and it may be cost-effective for smoking prevention to focus on the few (12%) easy to identify unstable low achievers who form 35% of smoking onsets. In addition, as parental support and democratic control reduced the likelihood of poor academic performance, promoting essential generic parenting skills from a young age may also prevent future onsets of smoking in adolescence