The use of high resolution digital surface models for change detection and viewshed analysis in the area around the pyramids of Giza, Egypt

One of the biggest threats to cultural heritage is related to their rapidly changing and developing surroundings. The Giza pyramid plateau is a prime example of this phenomenon, as it is threatened by the enormous urban expansion of Cairo over the last decades. Documenting, monitoring and modelling such a pressure requires accurate and detailed geographic data, which can be derived from recent up-to-date, high resolution satellite images. Remote sensing techniques have proven to be very useful to visualize and analyze urban sprawl and land use changes in two dimensions. The impact assessment of urban sprawl near specific heritage sites, however; needs to be complemented with accurate 2.5D-information. In an attempt to do so, digital surface models (DSMs) from Ikonos-2 (2005) and GeoEye-1 stereoscopic images (2009 and 2011) have been computed in order to analyze recent urban changes. Change detection methods are mainly developed for large scale high resolution aerial images; however this paper focuses on the one hand DSM creation and its challenges resulting in an improvement of 2.5D change detection method for small scale satellite imagery in mainly informal areas. On the other hand a view shed evolution is presented. The combination of the enhanced digital terrain extraction (eATE) module of Erdas Imagine® and ground control points collected in the field provides accurate and high resolution DSMs. The impact of shadow and different urban morphologies however influence the pixel-wise comparison of the two DSMs, which results in different approaches for different city districts. The resulting 2.5D change model clarifies not only the urban sprawl, but also the increase in building levels, directly related to pressure on the famous pyramids. This pressure is furthermore analyzed by creating different view sheds through time from the plateau towards the city and vice versa. An integration of population statistics complements the model, hence allowing it to become a useful policy instrument

A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

Archaeological prospecting using high-resolution digital satellite imagery : recent advances and future prospects; a session held at the computer applications and quantitative methods in archaeology (CAA) conference, Williamsburg, USA, March 2009

This paper summarizes papers given at a session on applications of satellite remote sensing in archaeological prospection held at the 2009 Computer Applications and Quantitative Methods in Archaeology Conference (CAA) in Williamsburg VA in March 2009. The overview of the contributions is followed by a general discussion of the state of the art of satellite-based archaeological prospection and how it relates to the more traditional field of aerial archaeology

Methods for the extraction of archaeological features from very high-resoluition Ikonos-2 remote sensing imagery, Hisar (southwest Turkey)

Archaeological research in the territory of Sagalassos is a multidisciplinary project covering scientific disciplines traditionally linked to archaeology and also new technologies such as very high-resolution remote sensing with sufficient radiometric and spatial resolution (<2.5 m). This paper focuses on the evaluation of GIS-, pixel- and object-based techniques for automatic extraction of archaeological features from Ikonos-2 satellite imagery, which are then compared to a visual interpretation of ancient structures. The study was carried out on the unexcavated archaeological site of Hisar (southwest Turkey). Although all techniques are able to detect archaeological structures from Ikonos-2 imagery, none of them succeed in extracting features in a unique spectral class. Various landscape elements, including archaeological remains, can be automatically classified when their spectral characteristics are different. However, major difficulties arise when extracting and classifying archaeological features such as wall remnants, which are composed of the same material as the surrounding substrate. Additionally, archaeological structures do not have unique shape or colour characteristics, which can make the extraction more straightforward. In contrast to autos matic extraction methods, a simple visual interpretation performs rather well. The methods presented in this paper can be applied with variable success to archaeological structures composed of the same material as the surrounding substrate, which is often the case. (c) 2006 Elsevier Ltd. All rights reserved.status: publishe

Methodologies for the Extraction of Archaeological Features from Very High-Resolution Ikonos-2 Remote Sensing Imagery, Hisar (Southwest Turkey)

status: publishe

Long-term effects of human impact on mountainous ecosystems, western Taurus Mountains

Aim: To investigate the human impact on eastern Mediterranean ecosystems in a subhumid to semi-arid region of the Near East. Location: This paper considers data from Bereket (1410-1440 m a.s.l.), an intramontane basin surrounded by the Kokayanik Tepe (1830 m a.s.l.) and the Beşparmak Daǧlari (2280 m a.s.l.), in the western Taurus Mountains of south-west Turkey. Methods: Late Holocene samples were collected along an 800-cm-deep sediment profile cored in the secondary valley of the Bereket basin. Descriptive vegetation data and modern pollen samples (moss polsters) were collected at elevational intervals of c. 15 m along an altitudinal transect from the Bereket basin (over Tepe Düzen, 1600 m a.s.l.) to Aǧlasun Daǧi (1700 m a.s.l.). Information about the spatial distribution of the present land cover was obtained from ASTER satellite imagery. Digital elevation-derived data and geological information were used to examine the relationship between actual land cover and other environmental variables. Results: The well dated Bereket sequence provides a unique record of biennial-to-decadal landscape changes driven primarily by intensive human impact from 360 cal. yr bc to 650 cal. yr ad. Since 360 cal. yr bc, over-exploitation of the land has led to altitudinal variation of tree lines, a destruction of the natural forest ecosystems (Pinus-Quercus cerris mixed forest), and an extensive spread of forest-steppe in the highlands. The present-day distribution of vegetation in the basin area shows that human activities remain the major factor influencing the character of modern ecosystems. Main conclusions: This research demonstrates the long-term local destructive effects of human impacts on the mountainous ecosystems in a small Anatolian intramontane basin since 360 cal. yr bc, and the capacity of these ecosystems to recover during periods of reduced human impact. The late Holocene history and modern vegetation characteristics show that the past and present-day distribution and composition of vegetation are influenced primarily by human activity, and that substrate, elevation, slope and orientation are of secondary significance. © 2007 The Authors.status: publishe

Late Holocene fire impact and post-fire regeneration from the Bereket basin, Taurus Mountains, Southwest Turkey

The 800 cm long sequence from the Bereket provides the first detailed fire history in the western Taurus Mountains for the last three millennia. The main disturbances occurred during the Beyşehir Occupation Phase (BO Phase), a period of intensive polyculture and dated at Bereket from ca. 2230 to 1550 cal yr BP. Four phases of local and extra-local fire periods have been recorded at 2320-2240, 1985-1970, 1865-1820 cal yr BP and post-AD 1950. The fire history established for the BO Phase is complex, with fire periods alternating with periods without local fires, as is the case for the late BO Phase from 1820 until 1550 cal yr BP. It is suggested that the past agricultural practices including fires cause a higher soil erodibility than agricultural practices without fires. A climatic shift towards aridity during Roman times may have triggered the observed change in fire regime but local processes, mainly human disturbances, appear to be the proximal cause of all recorded changes. In the Bereket surroundings, fires led to a simplification of the vegetation structure, favouring soil erosion, pastures and intensive cultivation. © 2008 University of Washington.status: publishe

The Analysis of Historical Maps as an Avenue to the Interpretation of Pre-Industrial Irrigation Practices in Egypt

The book in which this article has appeared, will be available Open Access as of April 2017.edition: 1status: publishe

Extracting archaeological features from very high resolution Quickbird-2 remote sensing imagery. A methodological approach based on Sagalassos (southwest Turkey)

status: publishe

The use of high resolution digital surface models for change detection and viewshed analysis in the urban area around the pyramids of Giza, Egypt

One of the biggest threats to cultural heritage is related to their rapidly changing and developing surroundings. The Giza pyramid plateau is a prime example of this phenomenon, as it is threatened by the enormous urban expansion of Cairo over the last decades. Documenting, monitoring and modelling such a pressure requires accurate and detailed geographic data, which can be derived from recent up-to-date, high resolution satellite images. Remote sensing techniques have proven to be very useful to visualize and analyze urban sprawl and land use changes in two dimensions. The impact assessment of urban sprawl near specific heritage sites, however; needs to be complemented with accurate 2.5D-information. In an attempt to do so, digital surface models (DSMs) from Ikonos-2 (2005) and GeoEye-1 stereoscopic images (2009 and 2011) have been computed in order to analyze recent urban changes. Change detection methods are mainly developed for large scale high resolution aerial images; however this paper focuses on the one hand DSM creation and its challenges resulting in an improvement of 2.5D change detection method for small scale satellite imagery in mainly informal areas. On the other hand a view shed evolution is presented. The combination of the enhanced digital terrain extraction (eATE) module of Erdas Imagine® and ground control points collected in the field provides accurate and high resolution DSMs. The impact of shadow and different urban morphologies however influence the pixel-wise comparison of the two DSMs, which results in different approaches for different city districts. The resulting 2.5D change model clarifies not only the urban sprawl, but also the increase in building levels, directly related to pressure on the famous pyramids. This pressure is furthermore analyzed by creating different view sheds through time from the plateau towards the city and vice versa. An integration of population statistics complements the model, hence allowing it to become a useful policy instrument