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Detecting the medieval cod trade: a new method and first results
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This paper explores the potential of stable isotope analysis to identify the approximate region of catch of cod by analysing bones from medieval settlements in northern and western Europe. It measures the d13C and d15N values of cod bone collagen from medieval control samples collected from sites around Arctic Norway, the North Sea, the Kattegat and the Baltic Sea. These data were considered likely to differ by region due to, for example, variation in the length of the food chain, water temperature and salinity. We find that geographical structuring is indeed evident, making it possible to identify bones from cod caught in distant waters. These results provide a new methodology for studying the growth of long-range trade in dried cod and the related expansion of fishing effortdimportant aspects of the development of commercialisation in medieval Europe. As a first test of the method, we analyse three collections of cod bones tentatively interpreted as imported dried fish based on a priori zooarchaeological criteria. The results tentatively suggest that cod were being transported or traded over very long distances since the end of the first millennium AD.
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RBINS Staff Publications
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Detection and correction of adjacency effects in hyperspectral airborne data of coastal and inland waters: the use of the near infrared similarity spectrum
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A method for the detection and correction of water pixels affected by adjacency effects is presented. The approach is based on the comparison of spectra with the near infrared (NIR) similarity spectrum. Pixels affected by adjacency effects have a water-leaving reflectance spectrum with a different shape to the reference spectrum. This deviation from the similarity spectrum is used as a measure for the adjacency effect. Secondly, the correspondence with the NIR similarity spectrum is used to quantify and to correct for the contribution of the background radiance during atmospheric correction. The advantage of the approach is that it requires no a priori assumptions on the sediment load or related reflectance values in the NIR and can therefore be applied to turbid waters. The approach is tested on hyperspectral airborne data (Compact Airborne Spectrographic Imager (CASI), Airborne Hyperspectral Scanner (AHS)) acquired above coastal and inland waters at different flight altitudes and under varying atmospheric conditions. As the NIR similarity spectrum forms the basis of the approach, the method will fail for water bodies for which this similarity spectrum is no longer valid.
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RBINS Staff Publications
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Detection limits of tidal-wetland sequences to identify variable rupture modes of megathrust earthquakes
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RBINS Staff Publications 2016
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Detection of Algal Blooms in European waters based on satellite chlorophyll data from MERIS and MODIS.
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A technique for algal-bloom detection in European waters is described, based on standard chlorophyll a concentration (Chl) data from two ocean-colour sensors, the Moderate Resolution Imaging Spectroradiometer (MODIS) and Medium Resolution Imaging Spectrometer (MERIS). Comparison of the two data sources shows good agreement in case 1 waters, whereas the difference is significant in coastal waters including turbid areas. A relationship between the water-leaving reflectance at 667 nm and Chl for case 1 waters was used to eliminate pixels where Chl retrieval is contaminated by backscatter from inorganic suspended matter. Daily Chl data are compared to a predefined threshold map to determine whether an algal bloom has occurred. In this study, a threshold map was defined as the 90th percentile of previous years' data to take account of regional differences in typical Chl levels, with separate maps for each sensor to take account of sensor-specific bias. The algal-bloom detection processing chain is described, and example results are presented.
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RBINS Staff Publications
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Detection of Bonobos (Pan Paniscus) in Tropical Rainforest Canopies Using Drone-Based Thermal Imaging: A First Step Towards Accurately Estimating Population Sizes?
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Surveying great ape populations is time-consuming and costly, and often relies on generalised parameters, resulting in imprecise population estimates. Using thermal imaging, through thermal cameras fitted on unmanned aerial vehicles, to detect primates directly from the air, may prove a useful alternative to conventional great ape population surveys. This may be especially true for bonobos (Pan paniscus) which, due to their large body size and nesting behaviour, could provide a uniquely identifiable thermal signature. We trialled the use of a thermal drone to record bonobos in their natural environment in the Democratic Republic of Congo, as a first step towards using the technique to survey great apes. Bonobos were observed asleep in their nests during all surveys at different flight speeds and heights, showing potential for the use of thermal drones as a method to survey great apes.
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RBINS Staff Publications 2022
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Detection of Bonobos (Pan Paniscus) in Tropical Rainforest Canopies Using Drone-Based Thermal Imaging: A First Step Towards Accurately Estimating Population Sizes?
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Surveying great ape populations is time-consuming and costly, and often relies on generalised parameters, resulting in imprecise population estimates. Using thermal imaging, through thermal cameras fitted on unmanned aerial vehicles, to detect primates directly from the air, may prove a useful alternative to conventional great ape population surveys. This may be especially true for bonobos (Pan paniscus) which, due to their large body size and nesting behaviour, could provide a uniquely identifiable thermal signature. We trialled the use of a thermal drone to record bonobos in their natural environment in the Democratic Republic of Congo, as a first step towards using the technique to survey great apes. Bonobos were observed asleep in their nests during all surveys at different flight speeds and heights, showing potential for the use of thermal drones as a method to survey great apes.
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RBINS Staff Publications 2022
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Detection of shipwrecks in ocean colour satellite imagery
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Waterborne swath acoustic and airborne laser systems are the main methods used to detect and investigate fully submerged shipwreck sites. In the nearshore, waterborne techniques are compromised as search tools as their effective swath is a function of water depth, necessitating very close survey line spacing in shallow water, increasing cost accordingly. Additionally, in turbid coastal waters bathymetric LiDAR is ineffective as it relies on clear non-turbid water. Therefore, the nearshore turbid zone represents a challenging area for archaeologists in the search for fully submerged archaeological sites. In this study, we describe a new methodology to detect the presence of submerged shipwrecks using ocean colour satellite imagery in turbid waters. We demonstrate that wrecks generate Suspended Particulate Matter (SPM) concentration signals that can be detected by high-resolution ocean colour satellite data such as Landsat-8. Surface SPM plumes extend downstream for up to 4 km from wrecks, with measured concentrations ranging between 15 and 95 mg/l. The overall ratio between the plume and background SPM concentrations is about 1.4. During slack tidal phases sediments in suspension settle to create fluffy mud deposits near the seabed. Scour pits developed around wrecks act as sinks where fine-grained suspended material is preferentially deposited at slacks. The scour pits subsequently act as sources for suspended material when the bottom current increases after slacks. SPM plumes develop immediately before maximum ebb or flood current is reached, during maximum current and immediately after. Particulate matter is suspended in sufficient concentrations to be detected in ocean colour data. The ability to detect submerged shipwrecks from satellite remote sensors is of benefit to archaeological scientists and resource managers interesting in locating wrecks and investigating processes driving their evolution.
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RBINS Staff Publications 2016
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Deterministic and stochastic effects drive the gut microbial diversity in cucurbit-feeding fruit flies (Diptera, Tephritidae)
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RBINS Staff Publications 2025
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Deux nouveaux gisements à otolithes de Téléostéens, dont une espèce nouvelle, dans l'Aquitanien continental du Midi de la France.
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RBINS Staff Publications
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Deuxième note sur les Rugueux coloniaux de l'Eifelien supérieur et de la base du Givetien à Wellin (bord sud du Bassin de Dinant, Belgique)
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RBINS Staff Publications 2016