Ralf Hesse | Landesamt für Denkmalpflege im Regierungspräsidium Stuttgart / State Office for Cultural Heritage Baden-Wuerttemberg (original) (raw)

Books by Ralf Hesse

Papers by Ralf Hesse

The Encyclopedia of Archaeological Sciences

Topography is perhaps the most important characteristic of the physical environment. It has direc... more Topography is perhaps the most important characteristic of the physical environment. It has direct relevance for human activities and also influences a multitude of other parameters, many of which are relevant for the availability and accessibility of resources. Digital models of the land surface thus have enormous analytical and modeling potential with regard to past human–environment interactions. These include, for example, visibility, movement, settlement, and resource exploitation. Different technologies are available for the creation of digital elevation models, of which airborne light detection and ranging (LiDAR) is presently by far the most favored due to canopy penetration, spatial resolution, and availability. High‐resolution, LiDAR‐based digital terrain models are commonly used for archaeological prospection. In combination with advanced visualization techniques, this has contributed to a focus shift from individual sites to archaeological landscapes.

Landscape Archaeology between Art and Science

High-resolution Digital Elevation Models (DEM) based on airborne LiDAR have emerged as a valuable... more High-resolution Digital Elevation Models (DEM) based on airborne LiDAR have emerged as a valuable new data source in archaeology. While such data are becoming increasingly available on a regional to national scale, their potential is far from being fully utilised. One field in which improvements can be expected is the optimisation of data processing with the goal of extracting anthropogenic features for archaeological prospection. Until recent years, however, most archaeological applications of LiDAR have been limited to the visual interpretation of the DEM. In this case, the detection of potential archaeological features depends to a large degree on the chosen illumination angles. Here, a data processing approach is presented which produces Local Relief Models (LRM) from LiDAR-derived high-resolution DEM. The LRM represents local, small-scale elevation differences after removing the large-scale landscape forms from the data. The LRM greatly enhances the visibility of small-scale, shallow topographic features irrespective of the illumination angle and allows their relative elevations as well as their volumes to be directly measured. This makes the LRM an improved basis for spatially extensive archaeological prospection over a wide range of landscapes. The LRM raster map of local positive and negative relief variations can be used for the mapping and prospecting of archaeological features such as burial mounds, linear and circular earthworks, sunken roads, agricultural terraces, ridge and furrow fields, kiln podia and mining sites. This approach is currently being used in a project aimed at the spatially complete archaeological mapping and prospection of Baden-Württemberg, covering an area of 35,751 km2. The goal is the verification and extension of the existing archaeological data base. An object-based local relief vector layer is produced as a by-product; however, due to the common agglutination of natural and anthropogenic features this cannot be efficiently used for archaeological prospection at present.

Landscape Archaeology between Art and Science, 2012

ABSTRACT The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of n... more ABSTRACT The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous studies. Availability of and access to water have long been recognised as the key issues for the habitability of valley oases in the coastal desert where agriculture depends on seasonal river discharge from the Andes. In general, the reason for cultural changes has often been seen in ‘natural disasters’ or climatic changes. We propose an alternative qualitative model to explain changes of human-environment interactions in the region. This model focuses on patterns arising from the exploitation of and adaptation to the limited – but on the whole not necessarily declining – resources of water and arable land. Agriculture along the rivers of the Peruvian coastal desert was probably first practised in the wide, gently sloping lowland valley floor areas at the foot of the Andes, where large tracts of land can be irrigated with relatively low expenditure of labour. Subsequent expansion of agriculture necessitated the utilisation of progressively marginal areas along the upstream reaches of the rivers. While the spatially limited valley floor areas can to a certain extent be irrigated with short irrigation canals, irrigation of the steep valley slopes of upvalley areas requires the labour-intensive construction and maintenance of canals and terraced fields in difficult – and arguably less productive – terrain. Diversion of water onto up-valley terraced fields can be expected to have reduced water availability in the lowland valley floor fields. Thus, the adaptation to the constraints of one limited resource (irrigable land) may have led to a suboptimal exploitation of another limited resource (water), leading to an overall decline in agricultural productivity per unit of arable land. Such a feedback between land use and water availability is consistent with archaeological findings such as declining population density and increasing conflict during the Early Intermediate Period.

Landscape Archaeology between Art and Science, 2012

Beim ersten 3D-Geländescan, der im Jahr 2003 für die archäologische Denkmalpflege in Baden-Württe... more Beim ersten 3D-Geländescan, der im Jahr 2003 für die archäologische Denkmalpflege in Baden-Württemberg angefertigt wurde, stand der frühkeltische Fürstensitz Heuneburg an der Oberen Donau im Zentrum des Interesses. An diesem Beispiel konnten erste Erfahrungen gesammelt und Einsatzmöglichkeiten für archäologische Fragestellun gen erprobt werden (vgl. hierzu Nachrichtenblatt 3/2007). Während der ersten Jahre der Verwendung von Laserscandaten für archäologische Fragestellungen in Baden-Württemberg lag der Fokus zunächst vor allem auf einzelnen Fundstellen oder Geländedenk malen. Als Beispiele sind etwa Grabhügel nekropolen oder der Obergermanisch-Raetische Limes zu nennen, wo nach gezielten Befliegungen detaillierte Beobachtungen und Auswertungen allein auf Basis der visuellen Analyse von Graustufenreliefbildern durchgeführt wurden. In den Jahren zwischen 2000 und 2005 wurde im Auftrag der staatlichen Landesvermessung BadenWürttemberg die gesamte Oberfläche des Bun des landes mit der n...

BIBLIOGRAPHIE CAMINO et al. 2015 J. Camino Mayor, E. Peralta Labrador & J. F. Torres Martinez (Hr... more BIBLIOGRAPHIE CAMINO et al. 2015 J. Camino Mayor, E. Peralta Labrador & J. F. Torres Martinez (Hrsg.), Las Guerras Astur-Cantabras (Gijon 2015). CEPEDA 2006a J. J. Cepeda Ocampo, Los campamentos romanos de La Poza (Cantabria). In: Arqueologia militar romana en Hispania 2 (Leon 2006) 683–690. CEPEDA 2006b J. J. Cepeda Ocampo, Pena Cutral (Cantabria). La via y los campamentos romanos. In: Actas del Homenaje al Profesor Juan Maria Apellaniz Castroviejo. Anejos Kobie 6 (Bilbao 2006) 391–402. CEPEDA et al. 2009 J. J. Cepeda Ocampo, J. M. Iglesias Gil, A. Ruiz Gutierrez & P. Sarabia Rogina, La ciudad de Iuliobriga y los campamentos romanos de La Poza (Cantabria). In: Limes XX. Anejos Gladius 13 (Madrid 2009) 631–638. CNIG (Centro Nacional de Informacion Geogra; ca) 2015 Presentacion del Centro de Descargas y Politica de Datos [http://centrodedescargas.cnig.es/CentroDescargas/index. jsp] (12.07.2016). COSTA 2015 J. M. Costa Garcia, Asentamientos militares romanos en el norte peninsular. Ap...

Seit einigen Jahren ist eine zunehmende Verfügbarkeit und Bedeutung von Lidar-basierten hochauflö... more Seit einigen Jahren ist eine zunehmende Verfügbarkeit und Bedeutung von Lidar-basierten hochauflösenden Digitalen Geländemodellen (DGM) in der archäologischen Forschung sowie in der Bodendenkmalpflege zu beobachten. Allerdings ist die ,konventionelle‘ Visualisierung derartiger Geländemodelle als schattiertes Reliebild (basierend auf simulierter gerichteter Beleuchtung des DGM) für viele Anwendungen in der Archäologie nicht optimal. Aus diesem Grund wird am Landesamt für Denkmalpflege Baden-Württemberg in Esslingen im Rahmen des von der Europäischen Kommission geförderten multinationalen Projektes ,Archaeolandscapes Europe‘ (www.archaeolandscapes.org) eine Lidar Visualisation Toolbox (LiVT) entwickelt. Im Folgenden sollen sowohl die Grundlagen verschiedener Visualisierungsmethoden als auch die Benutzung der Sotware im Überblick dargestellt werden.

Interpreting Archaeological Topography, 2013

Prostor, kraj, čas, 2018

Sva prava su pridržana. Niti jedan dio ovog izdanja ne smije se reprodukovati, pohranjivati ili r... more Sva prava su pridržana. Niti jedan dio ovog izdanja ne smije se reprodukovati, pohranjivati ili reprodukovati u bilo kojem obliku ili na bilo koji način, elektronski, mehanički, fotokopiranjem, snimanjem ili na drugi način, bez prethodnog pismenog odobrenja izdavača. © 2018 ZRC SAZU, Inštitut za antropološke in prostorske študije, autori, Založba ZRC. Slika na koricama knjige: Sjeverozapadni dio Slovenije. Lidarski podaci od 10 m prostorne rezolucije © ARSO, Slovenija. Regional Bureau for Science and Culture in Europe United Nations Educational, Scientific and Cultural Organization Ključne riječi lidar, lasersko skeniranje iz zraka, vizuelizacija, prikaz prostornih podataka, interpretacija, tumačenje, postavke, tehnike, alati, digitalni modeli visina Sažetak This guide provides an insight into a range of visualization techniques for highresolution digital elevation models (DEMs). It is provided in the context of investigation and interpretation of various types of historical and modern, cultural and natural small-scale relief features and landscape structures. It also specifies concise guidance for selecting the best techniques when looking at a specific type of landscape and/or looking for particular kinds of forms. The three main sections-descriptions of visualization techniques, guidance for selection of the techniques, and visualization tools-accompany examples of visualizations, exemplar archaeological and geomorphological case studies, a glossary of terms, and a list of references and recommendations for further reading. The structure facilitates people of different academic background and level of expertise to understand different visualizations, how to read them, how to manipulate the settings in a calculation, and choose the best suited for the purpose of the intended investigation.

Journal of Cultural Heritage, 2015

For millennia, humans have lived in regions which have been and/or are today characterised by ari... more For millennia, humans have lived in regions which have been and/or are today characterised by arid environmental conditions. Many archaeological sites are therefore located in deserts where they are subjected to specific conditions regarding their preservation, vulnerability, visibility and accessibility. The aim of this paper is to show how data from high and intermediate resolution satellite sensors and groundbased multi-image photogrammetry (Structure-from-Motion) can be combined to document damage to spatially extensive archaeological heritage in arid environments. In this approach, high-resolution satellite images (QuickBird) are used to locate archaeological sites and to verify the type of disturbance. Multiple sequential intermediate resolution satellite images (Landsat 7 ETM+) are used to document the spatial extent and temporal development of surface disturbances at the site and in the surrounding area. Structure-from-Motion (SfM) is used to document damage to a small segment of the archaeological site by creating a very high resolution DEM and orthophoto which are used for detailed damage assessment. The approach is exemplified using damage by off-road vehicles to a large Nasca period geoglyph in the coastal desert of southern Peru. It can be applied to document threats to spatially extensive archaeological sites in arid environments, such as large-scale looting, agricultural expansion or urban and industrial sprawl.

Journal of Arid Environments, 2014

Abstract Coppice dunes covered by epiarenic Tillandsia fog vegetation occur in the Peruvian coast... more Abstract Coppice dunes covered by epiarenic Tillandsia fog vegetation occur in the Peruvian coastal desert. To analyse the three-dimensional vegetation structure on such a coppice dune, a photogrammetric structure-from-motion approach is applied. A photogrammetric plant height map was derived from a digital surface model and a digital terrain model created by this approach. This plant height map is analysed in conjunction with stand-scale vegetation patterns, regional wind direction derived from migrating dunes, near-surface wind direction derived from the orientation of sand ripples and ground observations. Tillandsia vegetation patterns are non-random. Banded and reticulate patterns occur at stand scale. At metre to sub-metre scale, groups of tall plants occur in clusters as well as in rows aligned with air movement. While self-organisation processes related to maximising fog moisture capture by the plants and to coppice dune growth appear to control the development of the banded to reticulate pattern, retaining an upright growing position (and hence continued exposure to fog moisture on decadal time scales) by minimising aeolian erosion at the base of these rootless plants appears to control the development of rows and clusters at metre to sub-metre scale.

Tectonics, 2005

[1] Tectonic erosion at the base of the overriding plate plays an important role in controlling t... more [1] Tectonic erosion at the base of the overriding plate plays an important role in controlling the Peru margin bathymetry. However, the methodology of estimating the rates of tectonic erosion as used by Clift et al. [2003] is questioned. Several factors may have led Clift et al. [2003] to overestimate the rates of tectonic erosion: the assumption of an originally horizontal character of the 11 Ma erosional surface, the assumption of continuous isostatic equilibrium of the Peruvian forearc since 47 Ma, and not taking into account possible influences of changes in the rate of plate convergence and a shallowing of the subduction angle. [2] The rates of tectonic erosion calculated by Clift et al. [2003] are based on a seismic reflector interpreted as being the product of subaerial erosion at 11 Ma before present. The reconstructed depth of this reflector (after simulating the unloading of overlying sediment and allowing for sea level change) increases toward the SW, i.e., toward the trench. This is interpreted as ‘‘indicating faster basal tectonic erosion close to the trench, compared to more landward areas’’ (their Figure 8). The reflector is interpreted as having been originally horizontal, and subaerial erosion as having taken place at sea level. This interpretation is in conflict with the nature of subaerial erosion forms and processes: subaerial horizontal surfaces are very rare and are almost exclusively limited to accretion, not erosion (e.g., limnic sediments, fluvial overbank deposits). Both marine and fluvial erosional surfaces commonly have slopes of several degrees (0.5 to 11 for pediments [Dohrenwend, 1994], 1 to 5 for abrasion platforms (e.g., Goy et al. [1992], for examples from southern Peru), 3 for the land surface onshore of the study area (from the GTOPO-30 data set, average slope from 40 km inland to the coast). In any case, the slope will be toward the trench (for fluvial erosion toward base level, i.e., the sea; for abrasion also toward the sea). The sediment-unloaded cross sections of HIG-13 and HIG-14 of Clift et al. have slopes of approximately 2.5 to 3.5 , which is in agreement with subaerial erosional processes. It can thus be assumed that the slope of the reflector has not changed significantly and can therefore not be taken as an indicator for preferential basal erosion close to the trench. This also implies that the age of the erosion surface increases toward the trench. Furthermore, the faults affecting the sediments above the reflector [Clift et al., 2003, Figures 3 and 4] are not associated with noticeable vertical displacements of the reflector, which also indicates that no significant preferential basal erosion close to the trench has taken place. [3] One of the basic assumptions apparently made by Clift et al. [2003] is that the Peruvian forearc in the vicinity of the Lima Basin is, and has for the past 47 million years always been, in isostatic equilibrium. The possible effect of boundary forces on land and seafloor elevations, i.e., that the current elevation of the continental plate margin is considered to be a result of the balance between boundary forces and isostatic compensation [Mercier et al., 1992], is not taken into account. While the plate motion slowed from 123 mm/yr before 10.8 Ma to 61 mm/yr at present [Hampel, 2002], the rate of tectonic erosion as calculated by Clift et al. [2003] increased from 1.1 mm/yr before 11 Ma to 10 mm/yr after 11 Ma. This nineteenfold increase in the ratio of plate margin loss to relative plate motion is explained solely by the effect of the Nazca Ridge. A decrease in the rate of plate convergence as observed at the Peru margin should lead to a decrease in the uplifting component of the boundary forces and shift the balance toward isostatic compensation, and thus lead to subsidence of the surface. This subsidence due to the change in boundary forces must be separated from the subsidence due to tectonic erosion. Also, the possible effects of the rather abrupt shift in the subduction angle from steep south of the Nazca Ridge to shallow north of the ridge [Cahill and Isacks, 1992] on the observed subsidence are not discussed by Clift et al. [2003]. [4] While tectonic erosion at the base of the overriding plate certainly plays an important role in controlling the Peru margin bathymetry, it has to be noted that the results of Clift et al. [2003] are a maximum estimate of the tectonic erosion. More accurate estimates can be arrived at by critically assessing and adjusting the basic assumptions and by taking into consideration the influence of changes in plate convergence rate and subduction angle. TECTONICS, VOL. 24, TC2004, doi:10.1029/2004TC001636, 2005

Journal of Arid Environments, 2012

ABSTRACT Fog-dependent vegetation communities (lomas) occur in disjunct populations in the coasta... more ABSTRACT Fog-dependent vegetation communities (lomas) occur in disjunct populations in the coastal desert of Peru and northern Chile. Epiarenic species of Tillandsia develop characteristic metre-scale vegetation patterns which allow their distribution to be mapped in high-resolution satellite images. In combination with digital elevation models, topographic controls on their distribution are deduced. Dense Tillandsia lomas in the Pisco–Acarí sector of the Peruvian coastal desert occur at elevations between 467 and 1129 m; sparse populations have a slightly wider elevation range but are spatially much more extensive. Mean slope and aspect of dense Tillandsia lomas are 3.5° and 227°, respectively; however, scatter is large. Modelling based on the topographic properties of mapped dense Tillandsia lomas results in a much larger surface area than actually occupied by Tillandsia, implying that there must be other limiting factors besides local topographic controls. Comparison of the modelling results with the mapped distribution in conjunction with satellite images and digital elevation models indicates that the factors which limit the actual distribution of Tillandsia are (i) distance from the coast together with regional-scale lee situations behind the Cordillera de la Costa, (ii) local lee situations behind small topographic obstacles and (iii) wind strength and/or aeolian sediment transport.

Journal of Archaeological Science, 2013

ABSTRACT A recently published paper proposing a “strict solar alignment” of figurative rock carvi... more ABSTRACT A recently published paper proposing a “strict solar alignment” of figurative rock carvings in southern Sweden requires some critical and cautionary remarks. Using the paper “Strict solar alignment of Bronze Age rock carvings in SE Sweden” by N.-A. Mörner as a case study, various pitfalls and challenges in archaeoastronomical investigations are highlighted. Substantiating the idea of a relationship between the orientation of archaeological features such as rock carvings and astronomical events such as sunrise at winter solstice requires accurate and precise determination of (i) the orientation of the archaeological features and (ii) the azimuth of the astronomical event at the time of creation of the rock carvings, taking into account all influencing factors such as changes in Earth orbit parameters, surrounding topography and vegetation. Furthermore, possible motivations or intentions of Bronze Age rock carvers have to be considered. When trying to support a causal link between the orientation of archaeological features and astronomical events, it is indispensable to discuss and exclude possible alternative explanations, related to, for example, rock carving practice and visibility. Taking into account the above issues, there is no evidence for a solar alignment of the Järrestad rock carvings. The issues discussed using the Järrestad rock carvings as a case study are relevant to archaeoastronomical investigations in general.

Applied Geography, 2014

High-resolution digital elevation models, often derived from airborne lidar, are rapidly gaining ... more High-resolution digital elevation models, often derived from airborne lidar, are rapidly gaining importance in both archaeology and geomorphology, in particular where these two disciplines overlap in their interest in anthropogenic changes to the relief of the earth surface ("archaeogeomorphology"). Intergroup and interstate conflict are one aspect of human behaviour which commonly causes such relief changes. Conflict archaeology and conflict geomorphology, which are both young sub-disciplines within their scientific fields, have until now only touched upon a small part of the wide range of issues which they can encompass. While conflict archaeology has for a long time been almost synonymous with battlefield archaeology, the few papers explicitly discussing conflict geomorphology are mainly concerned with the impact of bombing on soil geomorphology. The application of high-resolution digital elevation models in investigating past conflicts can and should, however, encompass all geomorphological traces of conflict. These include defensive structures such as earthworks, primary and secondary traces of warfare itself (e.g. bomb craters and rubble mountains), conflict-related traces associated with military training and weapons testing facilities as well as, potentially, traces of conflict sustenance (e.g. conflict-related mining and infrastructure). Examples highlight the potential of high-resolution digital elevation models for the detection, mapping and quantification of conflict-related relief changes and thus for the understanding of conflicts. As suitable data are becoming increasingly available, the study of prehistoric and historic conflicts will benefit across the discipline boundaries between archaeology and geomorphology. In the field of heritage management, the detection, visualisation and protection at landscape-scale of what is often seen as "dark" heritage is expected to gain importance.

The Encyclopedia of Archaeological Sciences

Landscape Archaeology between Art and Science

Landscape Archaeology between Art and Science, 2012

Interpreting Archaeological Topography, 2013

Prostor, kraj, čas, 2018

Journal of Cultural Heritage, 2015

Journal of Arid Environments, 2014

Tectonics, 2005

Journal of Arid Environments, 2012

Journal of Archaeological Science, 2013

Applied Geography, 2014

Aeolian Research, 2012

In the coastal desert of southern Peru, sequential high-resolution satellite images document the ... more In the coastal desert of southern Peru, sequential high-resolution satellite images document the presence of short-lived and long-lived dust devil tracks. Dust devil tracks in the study region remain visible for less than 6 months in one area and for more than 4 years in another area. Short-lived tracks are generally darker than the surrounding ground surface. The brightness of long-lived tracks is often equal to that of their surroundings; they become visible due to a brighter edge along their margins. Different modes of formation related to ground surface properties are suggested to explain the differences in persistence and appearance. Dark, short-lived dust devil tracks are ascribed to the removal of silt-sized material from largely sand-sized surface materials. Long-lived tracks with bright margins are ascribed to coarser surface materials and the fallout of sand-sized particles along the track edges. Locating suitable areas on Earth for the study of dust devil tracks and distinguishing between different types of dust devil tracks is expected to further promote terrestrial analogue studies for Martian dust devil streaks.

Airborne lidar has become an important data source for large area archaeological prospection. How... more Airborne lidar has become an important data source for large area archaeological prospection. However, relatively few of the identified archaeological relief features are archaeological "sites" in the traditional sense. The vast majority of archaeological relief feature in airborne lidar data sets are various "scrapes and traces" created by or related to former activities. Among them, linear features of often unknown or ambiguous origin are extremely common. Arguably, most of these lines are traces of former field or cadastral boundaries. They are commonly expressed topographically as very low banks or ridges or as shallow linear depression. By itself, each of these features is usually undateable and of indefinable origin and function. Small- and large-area alignments and patterns in conjunction with rare cross-cutting relationships with topographical features of known age can, however, allow inferences regarding their age and origin. This is particularly relevant in the case of roman cadastral grids.

Historical maps are very valuable sources of information for understanding the past and for locat... more Historical maps are very valuable sources of information for understanding the past and for locating possible archaeological sites. However, due to various inaccuracies of such maps, many features shown on them can be difficult to locate. For example, many 18th century maps are based on a mix of survey methods (e.g. triangulation of important landmarks and less important places filled in based on walking distances or estimation) with very different error margins (from tens of metres to several kilometres). Standard methods for georeferencing therefore often result in maps which are severely distorted or in which only the well-surveyed points (usually those considered important at the time) are shown in the correct location. Features like roads, stream channels or artificial ponds (including commonly associated features such as bridges, gallows or mills) which are often depicted on historical maps can be very important from an archaeological point of view. However, their exact location may have been unimportant (or unknown) to the creator of the map. Interpretation of ALS (airborne lidar) visualisations can in many cases provide the necessary information to locate such features shown on historical maps. On the other hand, historical maps can support the interpretation of ALS visualisations. In many cases (and in particular for maps predating the 19th century), time and effort for a combined interpretation of historical maps and ALS visualisations are high.

Landscapes are continually changing, granted. But thinking about just what is changing (and how) ... more Landscapes are continually changing, granted. But thinking about just what is changing (and how) can become quite complicated long before we can even begin to think about devising metrics for detecting and quantifying such changes in remotely sensed data. One important reason for this is that landscapes are not only physical but are also socially constructed. A landscape may be significantly changed without any physical changes by “only” attaching a different meaning. On the other hand, a landscape may be experienced as constant, almost unchanging, despite severe physical changes, simply because the changes are not perceived as relevant or because they occur at temporal or spatial scales at which they are difficult to notice. From the perspective of aerial archaeology, we are looking at a very limited selection of physical characteristics to find traces of past changes. Just as the past landscapes that were experienced by members of former cultures, the archaeological landscapes that we study are only partially physical and to a large extent constructed. Technology is an important element in this construction. Different remote sensing methods, different data sets, different ways of presenting and analysis the data can and will lead to different perceptions, different landscapes, different pasts. Without any changes in either physical properties or analysed data, the cultural and scientific background and even the experience or the momentary focus of the observer influences just what kind of landscape, what kind of past is seen. Yet if perceiving, describing, analysing and understanding archaeological landscapes is bound to lead to tentative results, how can we approach changing landscapes?

High-resolution digital elevation models (usually based on airborne laser scanning) have been app... more High-resolution digital elevation models (usually based on airborne laser scanning) have been applied for archaeological research for more than ten years. In some regions, repeated coverage is becoming available, resulting in opportunities for the detection of changes which have occurred in-between the different surveys. However, while DEM change detection is in principle very simple, the practical application faces a number of challenges. These challenges include spatial resolution, horizontal and vertical accuracy as well as impacts of vegetation cover and data processing (e.g. strip adjustment and vegetation filtering). In addition to these challenges, the issue of comparing digital terrain models with digital surface models arises when lidar-derived DEMs are supplemented with lower-cost and often more easily acquired photogrammetric DSMs. As a result, the seemingly straightforward approach to monitoring archaeological landscapes by analysing multi-temporal elevation data sets is limited with respect to the detectability of relief changes and the achievable accuracy of the quantification of such changes. Because of the ongoing developments in terms of spatial resolution and accuracy, it is usually the (older) baseline data set which limits the applicability and informative value of change detection approaches. Therefore, it is expected that large area monitoring schemes based on airborne lidar will only become operational once repeated coverage by high-quality surveys becomes available. However, results achieved in small test areas in Baden-Württemberg are promising despite the mentioned challenges.

Airborne lidar has become one of the main data sources for the study of archaeological landscapes... more Airborne lidar has become one of the main data sources for the study of archaeological landscapes. In turn, the widespread application of airborne lidar has been stimulating landscape-scale notions and approaches in research as well as heritage management. It has repeatedly been noted that the archaeological landscapes which we study today are almost never the product of a single event or period of use but that they rather have to be considered as either palimpsests or as "messy landscapes". But how can we approach the multitemporality of archaeological landscapes if all that we have at hand are overlapping and mutually intersecting relief features in digital terrain models? How many different traces of former activities can we distinguish in a given area? How can we derive information on the chronology of these traces? Can we identify patterns of prevalence or preferential preservation of particular land uses and land use changes? How does the recognition of multitemporality affect our understanding of processes of land use change? How can we deal with the multitemporality of archaeological landscapes in research and heritage management contexts? Rather than providing ready-made answers to these and other questions, this presentation will explore possibilities and challenges by means of examples from various periods and from different parts of Europe.

Seit dem Jahr 2009 werden hochauflösende digitale Geländemodelle des Landes Baden-Württemberg flä... more Seit dem Jahr 2009 werden hochauflösende digitale Geländemodelle des Landes Baden-Württemberg flächendeckend ausgewertet, um bislang unbekannte archäologische Bodendenkmäler zu erfassen. Die digitalen Ge-ländemodelle werden durch die flugzeuggestützte Laser-Abtastung der Erdoberfläche (LIDAR) erfaßt. Da der Laserstrahl das Kronendach der Bäume durchdringen kann, erlaubt diese Methode die genaue Vermessung der Geländeoberfläche weitgehend unabhängig von der heutigen Vegetationsbedeckung. Im Bereich der Eppinger Linien erlaubt die Auswertung der LIDAR-Daten neben der Dokumentation des Erhaltungszustands beispielsweise auch quantitative Untersuchungen der Erdwerke und die Erfassung späterer Nutzungen.

Seit dem Jahr 2009 werden hochauflösende digitale Geländemodelle des Landes Baden-Württemberg flä... more Seit dem Jahr 2009 werden hochauflösende digitale Geländemodelle des Landes Baden-Württemberg flächendeckend ausgewertet, um bislang unbekannte archäologische Bodendenkmäler zu erfassen. Die digitalen Geländemodelle wurden vom das Landesamt für Geoinformation und Landentwicklung durch die flugzeuggestützte Laser-Abtastung der Erdoberfläche (LIDAR) erfaßt. Da der Laserstrahl das Kronendach der Bäume durchdringen kann, erlaubt diese Methode die genaue Vermessung der Geländeoberfläche weitgehend unabhängig von der heutigen Vegetationsbedeckung.

Neben Relikten früherer landwirtschaftlicher Nutzung sind in den LIDAR-Daten auch vielfältige Spuren (früh-)neuzeitlicher, aber auch vor- und frühgeschichtlicher Wirtschaftsweisen und Ressourcengewinnung zu erkennen. Zu diesen Spuren gehören beispielsweise die Dämme ehemaliger Mühl- und Fischweiher, Bergbaurelikte, Meilerplätze zur Holzkohleproduktion sowie Pech- und Kalköfen. Durch die flächendeckende Erfassung leistet die Auswertung der LIDAR-Daten einen wichtigen Beitrag zum Kenntnisstand über diese heute meist unter Wald verborgenen Objekte.

In einem Vortrag und auf Schautafeln werden bisherige Ergebnisse anhand von Beispielen präsentiert.

This lecture will present the principles of airborne laser scanning and DEM visualisation techniq... more This lecture will present the principles of airborne laser scanning and DEM visualisation techniques in the context of their application for large area archaeological prospection.

This lecture presents the principles of airborne laser scanning and DEM visualisation techniques ... more This lecture presents the principles of airborne laser scanning and DEM visualisation techniques in the context of their application for archaeological prospection. It is based mainly on the work within the state-wide archaeological prospection in Baden-Württemberg, Germany.

From 2009 to 2015, an ambitious project aimed at the spatially complete archaeological mapping an... more From 2009 to 2015, an ambitious project aimed at the spatially complete archaeological mapping and prospection of Baden-Württemberg (35,751 km2), using high-resolution digital elevation models based on airborne lidar. Tackling such a large project with very limited resources entailed challenges with respect to data management and processing and time-efficient workflows. A key role in reaching high performance (in terms of both mapping speed and archaeological feature detection) has been played by the development and adoption for archaeological questions of multiple DEM visualisation techniques. At the start, only two visualisation techniques (Shaded Relief and Local Relief Model) were used; by 2015 the number of techniques used had risen to seven (now including Sky-View Factor, Local Dominance, Laplacian of Gaussian, Openness and Multi-Scale Integral Invariants). On average, approximately thirty archaeological features have been detected per square kilometre, including former field boundaries, hollow ways, mining traces, charcoal burning platforms, dams or mounds, but also Iron Age rectangular enclosures, Roman roads or medieval castle sites. The results have far-reaching implications for both archaeological research and heritage management and protection. Verification and follow-up research of such large numbers of archaeological sites and features will pose considerable challenges. In the field of archaeological research, the newly discovered sites and may require reassessments of settlement patterns, resource exploitation and land use. In particular the very extensive traces of former field systems and hollow ways recognisable in lidar-DEM visualisations now afford landscape-scale studies. Such landscape perspectives will also require a rethinking of heritage management and protection practices: how can heritage protection and economic development coexist if the focus shifts from individual sites to entire landscapes? And in terms of the sheer numbers of archaeological sites and features detectable in large-area lidar data sets, how can we develop (and justify on scientific and economic grounds as well as with regards to the significance to the local population) priorities for protection?

Detecting traces of past conflicts in high-resolution digital elevation models requires appropriate data visualisation techniques. In the past few years, a variety of visualisation techniques (including, for example, shaded relief, sky-view factor, local relief model, openness or multi-scale integral in-variants) has been developed of adapted for archaeological applications. Since 2013, the open source software LiVT (developed at the State Office for Cultural Heritage Baden-Württemberg) is available as a toolbox to compute such visualisations. While the application of these visualisation techniques has the potential to greatly enhance the interpretative value of high-resolution digital elevation models, at least a basic understanding of the underlying algorithms is crucial for choosing appropriate techniques (depending e.g. on feature type and relief) and for correctly interpreting the resulting images. An overview of visualisation techniques will be given in the context of geomor-phological traces of past conflicts.

Contrast or histogram stretch is a common method of image processing. In aerial archaeology, it i... more Contrast or histogram stretch is a common method of image processing. In aerial archaeology, it is used to enhance the visibility of crop or soil marks in aerial photographs. In practice, the applicability and usefulness of this method is often compromised by the very inhomogeneous nature of many agricultural landscapes. The application of a single, overall contrast stretch for an aerial photograph or orthophoto commonly containing a mosaic of fields with different crops, grassland, forest and built-up areas often leads to unsatisfactory results. Readability of the image may even be reduced rather than improved. Therefore, aerial photographs are segmented by field parcel using cadastral data, and contrast stretch is applied to each field parcel. To further increase interpreter control over the image processing, histogram matching rather than simple contrast stretch is applied, resulting in similar histograms for all field parcels and a homogeneous, contrast-rich appearance of the resulting image. Tests of this approach indicate that it can be successfully applied for large-area analysis of aerial photography, in particular orthophotos, in agricultural landscapes. They do, however, also reveal some limitations, including for example non-correspondence between cadastral maps and actual crop parcels.

Seit dem Jahr 2009 werden hochauflösende digitale Geländemodelle des Landes Baden-Württemberg flä... more Seit dem Jahr 2009 werden hochauflösende digitale Geländemodelle des Landes Baden-Württemberg flächendeckend ausgewertet, um bislang un-bekannte archäologische Bodendenkmäler zu erfassen. Die digitalen Ge-ländemodelle wurden vom das Landesamt für Geoinformation und Landentwicklung durch die flugzeuggestützte Laser-Abtastung der Erdober-fläche (LIDAR) erfaßt. Da der Laserstrahl das Kronendach der Bäume durchdringen kann, erlaubt diese Methode die genaue Vermessung der Geländeoberfläche weitgehend unabhängig von der heutigen Vegetations-bedeckung.

Neben Relikten früherer landwirtschaftlicher Nutzung sind in den LIDAR-Daten auch vielfältige Spuren (früh-)neuzeitlicher, aber auch vor- und früh-geschichtlicher Wirtschaftsweisen und Ressourcengewinnung zu erkennen. Zu diesen Spuren gehören beispielsweise die Dämme ehemaliger Mühl- und Fischweiher, Bergbaurelikte, Meilerplätze zur Holzkohleproduktion sowie Pech- und Kalköfen. Durch die flächendeckende Erfassung leistet die Auswertung der LIDAR-Daten einen wichtigen Beitrag zum Kenntnisstand über diese heute meist unter Wald verborgenen Objekte.

Former field boundaries are commonly the most numerous archaeological relief features that are en... more Former field boundaries are commonly the most numerous archaeological relief features that are encountered when analysing airborne lidar data. In Baden-Württemberg, for example, they account for approximately 50% of all features mapped in the state-wide ALS-based archaeological prospection project. They can provide valuable insights regarding land use patterns and the localisation of settlements. However, in many cases the exact mapping of these features is not straightforward. For example, former field boundaries can be represented as incised or raised features. While in the case of ridge and furrow, each furrow marks the boundary of a narrow field, in the case of plough headlands or lynchets the field boundaries are raised features. In particular in situations where former field boundaries are only poorly or partially preserved due to subsequent land use changes or erosion, or where different field systems overlap, it can be a challenge to correctly identify and map these features.

The Prignitz is a region rich in archaeological sites. Archaeological relief features from Bronze... more The Prignitz is a region rich in archaeological sites. Archaeological relief features from Bronze age to modern are recognisable in lidar-based DEMs. Identification of these features benefits from the application of multiple visualisation techniques.

The potential of high-resolution digital elevation models (commonly based on airborne lidar) for ... more The potential of high-resolution digital elevation models (commonly based on airborne lidar) for the monitoring of archaeological sites and landscapes is commonly taken for granted. However, while the general approach for DEM change detection – subtracting one DEM from another – is very simple, its practical application faces some challenges. Repeated lidar surveys will increasingly become available in the future, but intercomparability issues may limit their applicability for the monitoring of archaeological sites and landscapes. DEMs derived from airborne lidar acquired over a single area commonly differ in terms of laser scanner type (single/multiple return, full waveform), scan angle, laser point density, actual vegetation cover, vegetation filtering and other processing steps, as well as the spatial resolution of the rasterized DEM. Georeferencing errors can have a pronounced effect on change detection results. Multiple DEMs may not be available for the desired monitoring period, and the high costs for commissioning multiple lidar surveys may be prohibitive for archaeological projects. To extend DEM change detection into the pre-lidar past, to increase the temporal resolution and to reduce costs, terrestrial laser scanning as well as photogrammetric (structure-from-motion) approaches can be applied. However, the intercomparability of DEMs derived from air-borne lidar and from photogrammetry is limited by the impact of vegetation cover or DEM generation.

AARG Annual Conference, 26-27 September 2013, Amersfoort, Netherlands

Many archaeological sites in coastal Peru are acutely threatened by looting, urban, industrial an... more Many archaeological sites in coastal Peru are acutely threatened by looting, urban, industrial and agricultural expansion and negligence. Even documenting the extent of destruction is often beyond the means of local archaeologists due to limited funding and manpower. In the face of immanent losses, structure-from-motion provides an easy-to-use, reliable, rapid and low-cost method for documenting threatened and damaged sites, thereby at least recording the current state of preservation and/or destruction. Repeated visits or comparison with aerial or satellite images allow to document changes over time. Examples from a field visit in late 2012 include damages caused by looting, agricultural expansion and off-road vehicles. A 135 m long segment of a large (3 km long) Nasca period geoglyph damaged by off-road vehicles was documented only weeks before much more severe damage was inflicted by the 2013 Dakar rally.

AARG Annual Conference, 26-27 September 2013, Amersfoort, Netherlands

In the past years there has been a tremendous increase in the availability of high-resolution dig... more In the past years there has been a tremendous increase in the availability of high-resolution digital elevation models based on airborne lidar and their application in archaeology. The “conventional” visualisation of these data as shaded relief images is often far from ideal for archaeological applications, and various alternative visualisation techniques have been developed to enhance the visibility of subtle relief features. Because these visualisation techniques were not commonly available, a software has been developed at the State Office for Cultural Heritage Baden-Württemberg, Germany, within the framework of the multinational project Archaeolandscapes Europe. The purpose of the Lidar Visualisation Toolbox (LiVT) is to provide an easy-to-use toolbox to compute various visualisations based on algorithms including Local Relief Model, Sky-View Factor, Exaggerated Relief, Accessibility, Cumulative Visibility, Local Dominance and Multi-Scale Integral Invariants. LiVT is published at https://sourceforge.net/projects/livt/ as open source software under the GNU General Public Licence.

Die hochauflösende Laservermessung aus der Luft eröffnet faszinierende und neue Einblicke in ganz... more Die hochauflösende Laservermessung aus der Luft eröffnet faszinierende und neue Einblicke in ganze Kulturlandschaften und hat sich in wenigen Jahren zu einem wichtigen Werkzeug der archäologischen Denkmalpflege entwickelt. Seit Mai 2009 läuft beim Landesamt für Denkmalpflege ein Projekt zur flächendeckenden archäologischen Erkundung Baden-Württembergs mittels hochauflösender digitaler Geländemodelle. Dieses Projekt wird seit 2010 im Rahmen des internationalen Projektverbundes Archaeolandscapes Europe durch die Europäische Kommission unterstützt.

The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous s... more The rise and decline of pre-Columbian cultures in coastal Peru has been the subject of numerous studies. Availability of and access to water have long been recognised as the key issue for the habitability of valley oases in the coastal desert where agriculture depends on seasonal river discharge from the Andes. The reason for cultural changes has often been seen in “natural disasters” or climatic changes.

Here, a different model is suggested to explain changes of human-environment interactions in the region. This model is driven by human behaviour in the exploitation of and adaptation to limited – but not necessarily declining – resources. Agriculture along the rivers of the Peruvian coastal desert was probably first practised in the wide, gently sloping valley floor areas at the foot of the Andes where large tracts of land can be irrigated with relatively low expenditure of labour. Irrigation agriculture in the Palpa Valley, for example, dates back at least 3000 years. Subsequent expansion of agricultural activities necessitated the utilisation of progressively marginal areas. While the spatially limited valley floor areas can to a certain extent be irrigated with short irrigation canals, irrigation of the steep valley slopes along the upstream reaches of the rivers requires the labour-intensive construction of longer canals and terraced fields in difficult – and arguably less productive – terrain. Diversion of river water onto these up-valley terraced fields can be expected to have reduced water availability in the lowland valley floor fields. Thus, the adaptation to the constraints of one limited resource (irrigable land) may have led to a suboptimal exploitation of another limited resource (water), leading to an overall decline in agricultural productivity per capita. This feedback between land use and water availability is consistent with archaeological findings such as declining overall population density and increasing conflict during the Early Intermediate Period.

High-resolution Digital Elevation Models (DEM) based on airborne LIDAR have emerged as a valuable... more High-resolution Digital Elevation Models (DEM) based on airborne LIDAR have emerged as a valuable new data source in archaeology. While such data are becoming increasingly available on a regional to national scale, their potential is far from being fully utilised. One field in which improvements can be expected is the optimisation of data processing with the goal of extracting anthropogenic features for archaeological prospection. Until now, however, most archaeological applications of LIDAR have been limited to the visual interpretation of the DEM. In this case, the detection of potential archaeological features depends to a large degree on the chosen illumination angles.

Here, a data processing approach is presented which produces Local Relief Models (LRM) from LIDAR-derived high-resolution DEM. The LRM represents local, small-scale elevation differences after removing the large-scale landscape forms from the data. The LRM greatly enhances the visibility of small-scale, shallow topographic features irrespective of the illumination angle and allows their relative elevations as well as their volumes to be directly measured. This makes the LRM an improved basis for spatially extensive archaeological prospection over a wide range of landscapes. The LRM raster map of local positive and negative relief variations can be used for the mapping and prospecting of archaeological features such as burial mounds, linear and circular earthworks, sunken roads, agricultural terraces, ridge and furrow fields, kiln podia and mining sites. This approach is currently being used in a project aimed at the complete archaeological mapping and prospection of Baden-Württemberg, covering an area of 35751 km2. The goal is the verification and extension of the existing archaeological data base. An object-based local relief vector layer is produced as a by-product; however, due to the common agglutination of natural and anthropogenic features this can not be efficiently used for archaeological prospection at present.

Trotz der großen historischen Bedeutung der Eisenproduktion in Luxemburg liegen bisher kaum gesic... more Trotz der großen historischen Bedeutung der Eisenproduktion in Luxemburg liegen bisher kaum gesicherte Erkenntnisse über die frühen Phasen der Eisengewinnung von der Latènezeit bis zum Mittelalter vor. Ein Zusammenhang der latène- und römerzeitlichen Besiedlung des Gebietes wurde zwar schon länger vermutet, konnte jedoch bisher nicht belegt werden. Dies ist unter anderem durch die großflächige Überprägung durch neuzeitliche Tagebaue bedingt. Moderne geophysikalische und Vermessungsverfahren können insbesondere unter diesen Bedingungen einen wichtigen Beitrag zur montanarchäologischen Prospektion leisten.

Im Untersuchungsgebiet südlich von Clemency (Südwest-Luxemburg) wurde eine Fläche von ca. 6,5 km2 mittels hochauslösendem flugzeuggestütztem Laser-Geländescan vermessen. Die Wahl des Befliegungsgebietes orientierte sich an der Lage der Eisenerzlagerstätten im räumlichen Kontext des keltischen Oppidums auf dem Titelberg und bedeutender Grabfunde von Clemency. Die hohe Auflösung (horizontal 1 m, vertikal im cm-Bereich) erlaubt die sichere Identifizierung von Befunden, welche mit bloßem Auge im Gelände kaum erkennbar sind. Bei Aufnahmen außerhalb der Vegetationsperiode ist selbst in dichtem Laubwald die Bodentopographie erfassbar. Mehrere Teilflächen wurden darüber hinaus mittels Geomagnetik kartiert.

Im Laserscan konnte eine Vielzahl von Befunden kartiert werden. Montanarchäologisch besonders interessant ist hier der Erzabbau im Tagebau. Hier konnten vier verschiedene Abbautypen identifiziert werden: (1) großflächige, terrassenartig am Hang angelegte neuzeitliche Tagebaue, (2) tiefe und großflächige, aber unregelmäßig geformte Tagebaue mit direktem Bezug zu aufgestauten Gräben (Erzwäsche), (3) runde bis ovale Pingen mit Durchmessern von ca. 2-5 m sowie (4) unregelmäßig geformte, flache Pingen mit Durchmessern von ca. 5-20 m. Die zeitliche Einordnung der verschiedenen Abbauspuren steht noch aus. Im räumlichen Zusammenhang mit den Abbauspuren konnte im Laserscan eine große Zahl von Podien (Meilerplätzen) sowie alte Wegenetze verschiedenen Alters identifiziert werden. Durch die Kombination von Laserscan, Geomagnetik und Geländeuntersuchungen konnten darüber hinaus Schlackehalden, welche im direkten Bezug zur Verhüttung stehen, nachgewiesen werden.

Understanding late Quaternary landscape evolution in southern coastal Peru is hampered by the pau... more Understanding late Quaternary landscape evolution in southern coastal Peru is hampered by the paucity of accurately dateable geoarchives. Therefore, local conditions remain obscure for much of the Quaternary. Key questions for paleoenvironmental reconstructions in this region are the persistence of hyperarid conditions throughout the Quaternary and particularly the Holocene, the occurrence and frequency of intensive local precipitation (commonly linked to El Niño events) and links between climatic conditions of the high Andes and the coast. While sedimentary sequences have been used to reconstruct flood and debris flow events in a number of studies from southern Ecuador, Peru and Chile, they rarely extend back into the Pleistocene.

Here we present a last Glacial sedimentary record of intensive local precipitation in the coastal desert (represented by coarse-grained autochthonous Quebrada deposits) and extremes in discharge of the exoreic Rio Grande de Nazca linked to precipitation in the Cordillera Occidental (represented by fine-grained flood deposits). The stratigraphy at the location allows the reconstruction of a sequence of deposition and erosion related to local and regional-scale precipitation and discharge events. Four charcoal samples taken at the location were used for radiocarbon dating. Three of the dates bracket a main phase of fluvial aggradation more than seven metres above the recent river bed; one date provides a minimum age for the end of debris flow deposition on the remnant landform.

A phase of exoreic flood sediments during the LGM was preceded and followed by phases of debris flow activity in the local catchment. Debris flow deposition ceased after 18.9-9.9 ka BP and before 2040 BP and was followed by Quebrada incision. Both debris flows and Quebrada incision require substantial amounts of local precipitation; the transition from accumulation to incision can therefore not be taken as a direct indicator for precipitation changes. Final river incision occurred after the Quebrada had incised to a level approximately 6 m above the recent river bed. It is shown that river incision was at most 8 m during the past 30 ka.

Für die peruanische Küstenwüste wird seit Jahrzehnten ein Zusammenhang zwischen Einschnitten in d... more Für die peruanische Küstenwüste wird seit Jahrzehnten ein Zusammenhang zwischen Einschnitten in der kulturellen Entwicklung und El Niño induzierten, episodisch auftretenden, katastrophalen Hochwasserereignissen diskutiert. Auch für den archäologischen Fundort La Muña, ca. 4 km südwestlich von Palpa (14°32‘S / 75°11‘W) am Ausgang eines nur 0,35 km² großen episodisch entwässernden Einzugsgebiets gelegen, gab es Hinweise auf einen möglichen Zusammenhang zwischen durch Starkniederschläge aufgelöste Murereignisse und einer Auflassung des Siedlungsplatzes.
Im Rahmen eines von der DFG geförderten Projektes wurden hier entlang einer Catena vom Talausgang über den Murkegel bis zum Ufer des Vorfluters Rio Grande acht Aufschlüsse und ein 20 m langer Schnitt angelegt, um die vertikale und laterale Differenzierung des Murkegels und die Verzahnung der Murkegelsedimente mit den fluvialen Sedimenten des Vorfluters untersuchen zu können. Die Tiefe der Aufschlüsse variierte im Murkegel zwischen 4,1 m und 2,9 m und im Bereich der Talaue des Rio Grande zwischen 2,5 m und 1,5 m.
Über die sedimentologischen Untersuchungen konnten im Murkegel insgesamt 15 durch autochtone Niederschläge induzierte Mur- (mindestens 6) oder feststoffreiche Hochwasserereignisse mit einer mittleren Wiederkehrzeit von etwa 60 Jahren nachgewiesen werden. Allerdings ergaben die Datierungen von Holzkohlefunden, dass diese Sequenz der Ereignissen erst um 1100 AD und damit mehrere hundert Jahre nach der archäologisch belegbare Auflassung von La Muña beginnt und damit keine Aussagen über einen Zusammenhang zwischen etwaigen Naturereignissen und der Auflassung von La Muña erlauben. Auch die Untersuchungen der Talauensedimente des Rio Grande ergaben ein überraschendes Ergebnis. Demnach wurde die hier knapp über 1 m mächtige Feinauflage innerhalb der letzten 300 Jahre durch eine Verlagerung und Eintiefung des Talwegs des Rio Grande und Sedimentation bei Hochwasserereignissen gebildet. Beide Befunde deuten auf nicht unerhebliche Veränderungen der Landschaft in unmittelbarer Nähe der Wüstung La Muña durch geomorphologische Prozesse hin und unterstreichen die Notwendigkeit, sowohl siedlungs- als auch landschaftsgeschichtliche Befunde zu datieren, wenn es um den Zusammenhang zwischen Siedlungs- und Landschaftsgeschichte geht.

Field systems are the most extensive traces of former human activities. For thousands of years, h... more Field systems are the most extensive traces of former human activities. For thousands of years, humans have modified their environment by clearing, subdividing and digging or ploughing the land to grow crops. The intentional or unintentional redistribution of soil creates distinct and recurring field system patterns which can survive as relief features for many centuries. Such patterns include ridge-and-furrow, terraces and lynchets, celtic fields, raised and sunken fields as well as plough headlands and alignments of clearing cairns. They record agricultural practices as well as their spatial distribution and extent and are therefore a important source of archaeological information. As it has increasingly been recognised that archaeological sites can only be fully understood if they are considered in their landscape context, the study of former field systems is gaining importance. This is greatly facilitated by new remote sensing techniques, in particular airborne LIDAR. The high-resolution digital elevation models based on airborne LIDAR are an ideal basis for the prospection, mapping and monitoring of archaeological sites and landscapes. The full potential of LIDAR is still being explored, and the application of novel visualisation techniques plays a key role. Using several case studies, this paper analyses the utility of different visualisation techniques to detect and map former field systems in LIDAR-based elevation models.

Registration is now open for the Lidar visualisation and interpretation workshop 2014 in Esslinge... more Registration is now open for the Lidar visualisation and interpretation workshop 2014 in Esslingen, Germany. The workshop will be a four-day event (including one field day) for students, graduate students and young professionals who are looking for theoretical background as well as hands-on experience with visualisation techniques for high-resolution digital elevation models (mainly but not exclusively based on airborne lidar) in the field of archaeology.

This is a simple tool to convert ASCII grid files to ASCII XYZ files. The ASCII grid files sh... more This is a simple tool to convert ASCII grid files to ASCII XYZ files.

The ASCII grid files should begin with header lines as follows:

ncols
nrows
xllcorner
yllcorner
cellsize
nodata_value

"UAVphoto is a simple tool that allows to calculate parameters like ground pixel size, motion blu... more "UAVphoto is a simple tool that allows to calculate parameters like ground pixel size, motion blur and sequential image overlap from UAV flight parameters (velocity and altitude) and camera parameters (focal length etc.). Calculation assumes vertical camera view.Image y dimensions are those in flight direction, image x dimensions are those perpendicular to flight direction.

Default camera values are for Canon G12 at the wide angle limit. Five to six seconds is the approximate minimum image interval using a CHDK (http://chdk.wikia.com) interval script. In continous shooting mode, a minimum interval of approximately one second can be achieved."

The intention behind this Lidar Visualisation Toolbox is to provide an easy-to-use, stand-alone a... more The intention behind this Lidar Visualisation Toolbox is to provide an easy-to-use, stand-alone application to create visualisations from high-resolution airborne LIDAR-based digital elevation data. LiVT also includes tools like raster file creation from xyz point clouds. A few mouse clicks and some processing time should be enough to go from an xyz ASCII file to a grey-scale SVF image, an LRM map or a percentage map of cumulative visibility. As LiVT does not include a data viewer, additional software will be necessary to display the processing results.

Current version is 1.0.0.23 (uploaded to sourceforge.net on 18 November 2013).

Aktuelle Forschungen zur Provinzialrömischen Archäologie in Hispanien

Ralf Hesse Der Einsatz von Hochstabphotographie und SfM zur Dokumentation archäologischer Funds... more Ralf Hesse
Der Einsatz von Hochstabphotographie und SfM zur Dokumentation archäologischer Fundstellen am Beispiel von Italica (Santiponce)

Aktuelle Forschungen zur Provinzialrömischen Archäologie in Hispanien

Ralf Hesse & José M. Costa-García LiDAR-Daten als Grundlage archäologischer Prospektionen in der ... more Ralf Hesse & José M. Costa-García LiDAR-Daten als Grundlage archäologischer Prospektionen in der Hispania romana