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The characteristics and form of heritage data are fundamental to its utility in a range of applications, particularly so for heritage agencies who have a remit in management, policy, and the creation and curation of national databases of monuments, sites, and landscapes. Written from the perspective of an archaeological survey function in a national heritage agency, this paper draws on preliminary outcomes from a research and development project that aims to proof protocols for creating systematic data across large areas drawing heavily on remotely sensed data. This recognises that a systemic consideration of the implications of changing technology and data is sometimes desirable, rather than gradual assimilation of developments into existing practice. In particular, the issues being addressed relate to the challenges and opportunities of proliferating remote sensed data and digital workflows. These include the strategic assessment of threat, consideration of fitness for purpose of different datasets relative to landscape characteristics, the documentation of processes and sources of information, the suitability of data structures, and the mechanisms for automating site detection and data creation.

Albedo is an important parameter in many environmental and renewable energy models. Satellite sensors can be used to derive broadband or narrowband albedos. However, the spatial resolution of such data can be insufficient in urban areas with complex morphology and land cover diversity. In this study, we propose the use of widely available aerial orthophotographs to derive visible band albedo in urban surfaces that can be effectively used in high-resolution applications. The solution is based on the estimation of the reflected irradiance captured by an RGB sensor and approximated by the brightness component in the hue-saturation-brightness (HSB) color model and incident solar irradiance modelled by the r.sun module in GRASS GIS. The visible band albedo values are calibrated by published reference values for selected land cover classes or, alternatively, by a spectroradiometer. The method is applied to the central part of Košice and compared to visible band albedo derived from the Landsat 8 OLI and Sentinel 2A sensors and previously published typical albedo values for various land cover classes, resulting in reasonable agreement. The proposed methodology is implemented using standard GIS tools that are easily applicable to any high-resolution urban data.

High-resolution aerial imagery may provide very detailed information about strong-convective wind events, which can be very useful to enhance and make more robust severe weather databases. Through an aerial analysis, unknown affected areas can be unveiled, large damaged zones or complex terrain events can be mapped, and in situ damage surveys can be completed. Comparing aerial orthophotographs or high-resolution satellite imagery taken before and after the event, damage to forest associated with EF1 + intensities rated with the Enhanced Fujita scale is easily observable. It is also possible to detect repaired parts on some types of roofs and buildings due to the occurrence of weak events and major damage on human-made structures in case of significant episodes. To illustrate the added value of using orthophotographs in forensic damage survey analysis, the 2 November 2008 strong-convective wind event in Catalonia (NE Iberian Peninsula) is revisited. Confirming previous studies, two different damage swaths, associated with the passage of two supercells during the early morning, are clearly identified in high-resolution aerial images. The additional information provided by orthophotograph analysis allowed extending the two damage paths and increasing the damage intensity of the event. It is concluded that both damage tracks are related to tornadoes, which are rated as an EF2 and an EF3, the second being the strongest tornado ever registered in Catalonia, one of the most tornado-prone regions of southern Europe. [ABSTRACT FROM AUTHOR]

While the National Record of the Historic Environment (NRHE) in Scotland contains valuable information on more than 170,000 archaeological monuments, it is clear that this dataset is conditioned by the disposition of past survey and changing parameters of data collection strategies over many decades. This highlights the importance of creating systematic datasets, in which the standards to which they were created are explicit, and against which the reliability of our knowledge of the material remains of the past can be assessed. This paper describes issues of data structure and reliability, then discussing the methodologies under development for expediting the progress of national-scale mapping with specific reference to the Isle of Arran. Preliminary outcomes of a recent archaeological mapping project of the island, which has been used to develop protocols for rapid large area mapping, are outlined. The primary sources for the survey were airborne laser scanning derivatives and orthophotographs, supplemented by field observation, and the project has more than doubled the number of known monuments of Arran. The survey procedures are described, followed by a discussion of the utility of 'general purpose' remote sensed datasets, focusing on the assessment of strengths and weaknesses for rapid mapping of large areas. [ABSTRACT FROM AUTHOR]

The aim of this paper is to integrate different sources of spatial information (cadastres, orthophotographies and satellite images), which also require different treatments, in order to be able to measure and evaluate the sealing of soils in a recent urban development project in the southeast of the city of Madrid, in order to establish a methodology of space-time monitoring of this parameter. Another objective is to show if the current urbanization process respects the European environmental guidelines in which waterproofed or sealed soil, inherent in economic development, coexists with natural spaces that allow to maintain some ecological functions such as softening the urban microclimate, setting growth levels of CO2 in stable figures in line with European environmental quality and standards, damping floods and preserving biodiversity. The sealing values of soils measured from different sources and using complementary techniques generate similar results when the waterproofing is higher than 60%. However, the calculations obtained from satellite images vary according to their spatial resolution and the type of treatment applied. With the Spot satellite the sealing values are close to 24%, while with the Sentinel-2 the percentage rises to 30%. Orthophotographies offer greater spatial precision, so sealing levels (<20%, 20-40%, 40-60% and > 60%) have been established, but their low temporal resolution prevents continuous monitoring, at least annually. Therefore, it is necessary to use different cartographic sources when carry out a study of urban areas, since the different temporal, spatial and spectral resolutions allow to visualize different characteristics in each of them. Consequently, their complementarity helps to correct the possible inadequacies of each of them. [ABSTRACT FROM AUTHOR]

While the National Record of the Historic Environment (NRHE) in Scotland contains valuable information on more than 170,000 archaeological monuments, it is clear that this dataset is conditioned by the disposition of past survey and changing parameters of data collection strategies over many decades. This highlights the importance of creating systematic datasets, in which the standards to which they were created are explicit, and against which the reliability of our knowledge of the material remains of the past can be assessed. This paper describes issues of data structure and reliability, then discussing the methodologies under development for expediting the progress of national-scale mapping with specific reference to the Isle of Arran. Preliminary outcomes of a recent archaeological mapping project of the island, which has been used to develop protocols for rapid large area mapping, are outlined. The primary sources for the survey were airborne laser scanning derivatives and orthophotographs, supplemented by field observation, and the project has more than doubled the number of known monuments of Arran. The survey procedures are described, followed by a discussion of the utility of ‘general purpose’ remote sensed datasets, focusing on the assessment of strengths and weaknesses for rapid mapping of large areas.

Zusammenfassung: In der Region Wielkopolska (Großpolen) befinden sich eine Reihe befestigter Siedlungen, die in die frühe Eisenzeit datieren und einzigartige Merkmale hinsichtlich ihrer Funktion, Genese und Chronologie aufweisen. Bedeutsam sind diese Siedlungsbefunde nicht nur im Blickwinkel der Vorgeschichte Polens, sondern auch im überregionalen Kontext. Die Deutung dieser Siedlungen, die bereits über längere Zeiträume im Mittelpunkt der Forschung standen und dabei unter verschiedenen räumlichen und fachspezifischen Fragestellungen betrachtet wurden, ist sehr unterschiedlich, wird in der Forschung jedoch als eher unbefriedigend angesehen. Neben jenen Siedlungen gibt es noch weitere Fundplätze, die jedoch zumeist in nur wenigen Kampagnen oder in vereinzelten Sondagen archäologisch untersucht wurden. Ausgenommen davon sind die Siedlungen Biskupin und Sobiejuchy. Auch die Ergebnisse jener Forschungen müssen unter verschiedenen Aspekten als wenig zufriedenstellend bezeichnet werden. Obgleich der Forschung heutzutage ein breites Spektrum fortschrittlicher und ausgefeilter Technologien für die Gewinnung absoluter Datierungen zur Verfügung steht, liegen doch für die hier betrachtete Region nur wenige Fakten zur Chronologie befestigter hallstattzeitlicher Siedlungen vor. Aus diesen Gründen begannen die Autoren ein Projekt zur Erarbeitung und Sammlung genau jener Schlüsselinformationen. Die wichtigsten Verfahren zur Gewinnung absoluter Daten waren dabei neben der Dendrochronologie Radiokarbonuntersuchungen an Hölzern, organischen Materialen aus den Kulturschichten sowie an osteologischem Material, ferner Lumineszenzuntersuchungen von Keramik. Ein weiterer wichtiger Baustein des Projekts bestand im Vergleich der auf diesem Weg gewonnenen Daten mit solchen aus traditionellen archäologischen Studien (etwa bezüglich der Änderung von Keramikstilen).Die Verfasser strebten außerdem an, die Entwicklung befestigter hallstattzeitlicher Siedlungen mit Hilfe der Fernerkundung, der Luftaufklärung, geophysikalischer Untersuchungen und digitaler Geländemodelle (Geomagnetik, 3D-Modellierungen, Orthofotografien) besser zu verstehen. Der vorliegende Beitrag stellt einen vorläufigen Bericht über die entsprechenden Untersuchungen in Großpolen dar. Résumé: Le caractère des habitats fortifiés de l'époque de Hallstatt dans la région de Wielkopolska est unique en ce qui concerne leur évolution interne, le rôle qu'ils ont pu remplir, leur origine et leur chronologie. Il s'agit d'un groupe de monuments fondamentaux, et leur étude dépasse le simple examen d'un aspect particulier de la préhistoire polonaise. Ces habitats, qui ont été étudiés au cours des ans de façon fort variable et sous des angles divers, sont mal connus, comme la littérature spécialisée l'a relevé depuis longtemps. Il existe, en dehors des sites fouillés au cours de longues campagnes pluriannuelles (tels Biskupin et Sobiejuchy), des sites qui n'ont fait l'objet que de courtes campagnes d'une ou deux saisons ou des sites ou seuls de petits sondages ont été faits. De plus, l'analyse des résultats de ces fouilles laisse en général aussi à désirer. Malgré les possibilités offertes par les nouvelles méthodes de datation absolue, notre connaissance des habitats fortifiés de l'époque de Hallstatt dans la région de Wielkopolska est encore fort maigre. Les auteurs ont ainsi initié un nouveau projet dont l'objectif est d'obtenir plus d'informations sur des aspects de ces habitats non explorés ou insuffisamment étudiés. La datation absolue par radiocarbone et par dendrochronologie (d'éléments structurels en bois, de matériel organique provenant de couches culturelles, d'ossements) et par luminescence (pour la céramique) constitue l'objectif principal de cette étude. De plus nous tentons d'établir des corrélations entre les dates obtenues et la masse de matériel archéologique récupéré afin de vérifier et de modifier les dates obtenues par les méthodes traditionnelles de datation (basée sur les changements typologiques de la céramique). Enfin, nous espérons obtenir des informations plus étendues sur l'évolution des habitats fortifiés de l'époque de Hallstatt de la région par l'application de méthodes de prospections telles la photographie aérienne, les prospections géophysiques, les modèles numériques de terrain (par magnétométrie, modèles en 3D, ortho-photographies). Notre article est un rapport préliminaire sur l'étude en cours des habitats fortifiés de Wielkopolska. Abstract: The unique nature of the Early Iron Age fortified settlements of Wielkopolska, in terms of their internal development, alleged function, genesis and chronology, places them in a group of monuments that have a fundamental meaning. Studying these sites goes beyond understanding this particular aspect of Polish prehistory. The recognition of these settlements, studied over the years and considered under various spatial and subject-specific angles, is very uneven and, in general, unsatisfactory, as has long been pointed out in the literature. Apart from the sites explored in long-term excavation campaigns, there are sites where reconnaissance work was carried out over only one or two seasons (excepting Biskupin and Sobiejuchy) or where only sondages were made. Furthermore, the analysis of the results of these investigations is, in general, also fairly unsatisfactory. Despite the opportunities offered by the current methods of absolute dating, we still know very little about the chronology of the fortified Hallstatt settlements of Wielkopolska. Hence the authors have started a new project aimed at gathering key information that has not so far been obtained or that has been insufficiently investigated. The most important element is absolute dating by dendrochronological and radiocarbon methods (timber structural elements, organic material from culture layers, osteological material) and luminescence (ceramics). Another important aspect consists of attempts at correlating the absolute dates obtained with the mass of archaeological material to verify and modify the traditional dating methods (changes in pottery styles). Last but not least we aim to obtain broader information regarding the development of all Hallstatt fortified sites from the study area through remote sensing, which includes aerial reconnaissance, geophysical surveys, digital terrain models (magnetometry maps, 3D models, orthophotographs). This article is a preliminary report on the new investigations of the Wielkopolska fortified settlements currently being conducted by the authors. [ABSTRACT FROM AUTHOR]

The article discusses the study of gully erosion in analyzing the evolution of a valley bottom gully in relation to land use vegetation cover and exploring the role of land use and vegetation cover on the topographical threshold concept. It cites the study area located in the Parapuños experimental catchment situated in southwest Spain. It concludes that historical aerial photographs and geomatic technologies are useful in understanding the environmental evolution and relationships between land use, vegetation cover and degradation processes.

Albedo is an important parameter in many environmental and renewable energy models. Satellite sensors can be used to derive broadband or narrowband albedos. However, the spatial resolution of such data can be insufficient in urban areas with complex morphology and land cover diversity. In this study, we propose the use of widely available aerial orthophotographs to derive visible band albedo in urban surfaces that can be effectively used in high-resolution applications. The solution is based on the estimation of the reflected irradiance captured by an RGB sensor and approximated by the brightness component in the hue-saturation-brightness (HSB) color model and incident solar irradiance modelled by the r.sun module in GRASS GIS. The visible band albedo values are calibrated by published reference values for selected land cover classes or, alternatively, by a spectroradiometer. The method is applied to the central part of Košice and compared to visible band albedo derived from the Landsat 8 OLI and Sentinel 2A sensors and previously published typical albedo values for various land cover classes, resulting in reasonable agreement. The proposed methodology is implemented using standard GIS tools that are easily applicable to any high-resolution urban data. [ABSTRACT FROM AUTHOR]

During the Mitch Hurricane event (October 1998), severe floods occurred in the village of La Trinidad (Departamento de Estelí, NW Nicaragua), which spreads at the margin of La Trinidad river. As a consequence, the need for hazard assessment and land use planning to reduce the effects of these natural processes arose. Nicaragua is a developing country, which means that there is a scarcity of good quality data on which to base these hazard assessments (i.e., lack of detailed topographic maps, lack of meteorological and discharge data series). Therefore, the main objective of the present work was to generate a flood hazard map of La Trinidad by means of a simple method, with a resulting map easy to understand and to use by the municipality for land use planning. There is no topographic map of the area at a more detailed scale than 1:50,000. So the main document that supports all the data and on which the final hazard map was based is the orthophotograph at 1:5,000 scale (generated from vertical aerial photographs taken in 2000). The method used was based on classical interpretation of vertical aerial photographs (pre Mitch and a post Mitch event), detailed field work, inquiries among the population and analysis of the main pattern of storms occurring in the area. All these data allowed the reconstruction of different extensions and water levels corresponding to events of different frequency and magnitude, and the qualitative association of them to three hazard levels by means of energy and frequency. The use of orthophotographs of 1:5,000 proved to be very useful both for the development of the work and for the presentation of the final map, because they are very easily understandable for people not trained in the interpretation of topographic maps. [ABSTRACT FROM AUTHOR]

A simple methodology for recording rock art has been recently developed in Australia and tested on Aboriginal rock art, including both petroglyphs and pictographs (engraved and painted images, respectively). The approach was based on commercial photogrammetric software and consumer-grade digital cameras, because it was believed that archaeologists, conservators and site managers need simple and cost-effective methods to record and document rock art. This methodology has been adopted subsequently by the Northumberland and Durham Rock Art Project working in conjunction with English Heritage, to assist in recording 1500 prehistoric engraved panels located across the north-east of England. Significantly, the fieldwork was carried out by enthusiastic volunteers, willing to sacrifice their weekends to capture imagery suitable for digital photogrammetry. This paper explains briefly how the recording technique was developed in Australia before indicating how expertise and equipment were integrated to allow UK-based volunteers to carry out data acquisition and, perhaps surprisingly, also the photogrammetry. This will demonstrate the value of mobilising the voluntary sector for heritage recording, which is feasible only if recording methodologies are based on cheap and simple instrumentation. [ABSTRACT FROM AUTHOR]

Abstract: The Pacific oyster, Crassostrea gigas, well known throughout the world because of its ability to adapt to a wide range of environmental conditions, was introduced for cultivation into France on a massive scale in the 1970s. With global warming, the reproductive population, confined at the beginning to the south of the French Atlantic coast, became established at more northern latitudes (above 45° 58′ N), and wild C. gigas began to colonize coastal areas such as our study site, Bourgneuf Bay (1°–2° W, 46°–47° N), an oyster-farming site. An original approach, based on orthophotograph analysis and in situ biomass sampling, revealed that, in the northern part of this bay, more than 70% of the total C. gigas biomass was composed of wild oysters (i.e. C. gigas not bred by oystermen). The analysis of the spatial distribution of wild oysters indicated that 75% of the stock consisted of wild oysters in natural beds (rocky areas) and on low retaining walls of former fisheries. Wild C. gigas also colonized oyster-farming structures with lower biomasses (21% of the stock composed of wild oysters), but locally they could reach densities of up to 55 kg.m−1 i.e. 2.5 times the mean biomass of cultivated oysters. The economic and ecological consequences of this colonization by C. gigas of an oyster culture site are discussed. Wild oyster seems to be the principal trophic competitor of cultivated oysters in Bourgneuf Bay. This may partly explain the decrease in growth of cultivated oysters observed in this bay during the last decade. Moreover, the trophic and spatial competition exerted by wild oysters may also affect the native biota and, in particular, the honeycomb worm Sabellaria alveolata. The results obtained in this study have led oyster farmers and regional authorities to modify oyster-farming practices and to destroy wild oyster stocks in concession areas. [Copyright &y& Elsevier]

Abstract This article presents a complete mathematical model, which translates discrepancies between two orthophotographs created from different photographs, into precise corrections of the Digital Elevation Model (DEM). These corrections are the differences from the real surface and, if applied over the existing DEM, can produce a more accurate one. The mathematical model is straightforward, and is not approximate, and therefore there is no need for iterations. Possible applications include checking of automatically created DEMs, refinement of existing DEMs using aerial photographs and update of orthophotographs based on the previous DEM and new imagery. [ABSTRACT FROM AUTHOR]