-
Atmospheric correction of Sentinel-3/OLCI data for mapping of suspended particulate matter and chlorophyll-a concentration in Belgian turbid coastal waters
-
The performance of different atmospheric correction algorithms for the Ocean and Land Colour Instrument (OLCI) on board of Sentinel-3 (S3) is evaluated for retrieval of water-leaving radiance reflectance, and derived parameters chlorophyll-a concentration and turbidity in turbid coastal waters in the Belgian Coastal Zone (BCZ). This is performed using in situ measurements from an autonomous pan-and-tilt hyperspectral radiometer system (PANTHYR). The PANTHYR provides validation data for any satellite band between 400 and 900 nm, with the deployment in the BCZ of particular interest due to the wide range of observed Near-InfraRed (NIR) reflectance. The Dark Spectrum Fitting (DSF) atmospheric correction algorithm is adapted for S3/OLCI processing in ACOLITE, and its performance and that of 5 other processing algorithms (L2-WFR, POLYMER, C2RCC, SeaDAS, and SeaDAS-ALT) is compared to the in situ measured reflectances. Water turbidities across the matchups in the Belgian Coastal Zone are about 20–100 FNU, and the overall performance is best for ACOLITE and L2-WFR, with the former providing lowest relative (Mean Absolute Relative Difference, MARD 7–27\%) and absolute errors (Mean Average Difference, MAD -0.002, Root Mean Squared Difference, RMSD 0.01–0.016) in the bands between 442 and 681 nm. L2-WFR provides the lowest errors at longer NIR wavelengths (754–885 nm). The algorithms that assume a water reflectance model, i.e. POLYMER and C2RCC, are at present not very suitable for processing imagery over the turbid Belgian coastal waters, with especially the latter introducing problems in the 665 and 709 nm bands, and hence the chlorophyll-a and turbidity retrievals. This may be caused by their internal model and/or training dataset not being well adapted to the waters encountered in the BCZ. The 1020 nm band is used most frequently by ACOLITE/DSF for the estimation of the atmospheric path reflectance (67\% of matchups), indicating its usefulness for turbid water atmospheric correction. Turbidity retrieval using a single band algorithm showed good performance for L2-WFR and ACOLITE compared to PANTHYR for e.g. the 709 nm band (MARD 15 and 17\%), where their reflectances were also very close to the in situ observations (MARD 11\%). For the retrieval of chlorophyll-a, all methods except C2RCC gave similar performance, due to the RedEdge band-ratio algorithm being robust to typical spectrally flat atmospheric correction errors. C2RCC does not retain the spectral relationship in the Red and RedEdge bands, and hence its chlorophyll-a concentration retrieval is not at all reliable in Belgian coastal waters. L2-WFR and ACOLITE show similar performance compared to in situ radiometry, but due to the assumption of spatially consistent aerosols, ACOLITE provides less noisy products. With the superior performance of ACOLITE in the 490–681 nm wavelength range, and smoother output products, it can be recommended for processing of S3/OLCI data in turbid waters similar to those encountered in the BCZ. The ACOLITE processor for OLCI and the in situ matchup dataset used here are made available under an open source license.
Located in
Library
/
RBINS Staff Publications 2021
-
Australian Cleotychini planthoppers: review of the genus Cleotyche Emeljanov, 1997 with three new species (Hemiptera: Fulgoromorpha: Dictyopharidae)
-
Located in
Library
/
RBINS Staff Publications 2022
-
Authorship and date of five family-series nomina in Oligochaeta (Annelida): Lumbricidae, Naididae, Enchytraeidae, Tubificidae and Lumbriculidae
-
Located in
Library
/
RBINS Staff Publications 2021
-
Avancées récentes sur le Paléogène inférieur des bassins parisien et belge à partir des mammifères
-
La compréhension progressive des différents réchauffements climatiques intenses du Paléogène inférieur (PETM, ETM-2, EECO…) a créé un intérêt évident pour une stratigraphie de plus en plus fine des bassins sédimentaires qui ont enregistrés ces événements. Ces derniers, identifiés sur base géochimique, demandent à être corrélés avec les événements biologiques qui en découlent et qui ont été, eux aussi, enregistrés dans ces bassins. Dans ce cadre, les bassins parisien, de Londres et de Belgique, formant le sud du Bassin de la Mer du Nord, représentent des modèles de choix pour la communauté géoscientifique de par leur reconnaissance historique et les étages internationaux Lutétien, Yprésien et Thanétien qu’ils ont respectivement permis de définir. Si les connaissances sur les dépôts marins ont fait d’énormes progrès notamment grâce aux études micropaléontologiques détaillées, qu’en est-il aujourd’hui des dépôts continentaux souvent délaissés par leur complexité à être interprétés? Vingt-cinq ans d’expertise en biochronologie mammalienne de notre équipe bruxelloise et de ses collaborateurs sont ici survolés, mettant en exergue l’utilité des mammifères en stratigraphie et paléogéographie. L’exposé porte tant sur des taxons marqueurs que des faunes entières issues de sites historiques ou nouveaux du Bassin parisien et de son complémentaire le bassin belge (Hainin, Maret, Rivecourt, Dormaal, Erquelinnes, Meudon, Sotteville-sur-Mer, Egem, Oosterzele…). Ainsi, des niveaux de référence de l’échelle biochronologique européenne des mammifères du Paléogène (MP) sont précisés, de nouveaux âges à mammifères européens sont identifiés et la stratigraphie tant à l’échelle locale que nord-ouest européenne est affinée. Malgré tout le travail accompli, les questions sont nombreuses et beaucoup reste à faire tant l’étude des faunes de mammifères est incomplète!
Located in
Library
/
RBINS Staff Publications 2021
-
Avian foraging on an intertidal mudflat succession in the Eocene Tanjung Formation, Asem Asem Basin, South Kalimantan, Indonesia Borneo
-
Moderately diverse trace fossil assemblages occur in the Eocene Tambak Member of the Tanjung Formation, in the Asem Asem Basin on the southern coast of South Kalimantan. These assemblages are fundamental for establishing depositional models and paleoecological reconstructions for southern Kalimantan during the Eocene and contribute substantially to the otherwise poorly documented fossil record of birds in Island Southeast Asia. Extensive forest cover has precluded previous ichnological analyses in the study area. The traces discussed herein were discovered in newly exposed outcrops in the basal part of the Wahana Baratama coal mine, on the Kalimantan coast of the Java Sea. The Tambak assemblage includes both vertebrate and invertebrate trace fossils. Invertebrate traces observed in this study include Arenicolites, Cylindrichnus, Diplocraterion, Palaeophycus, Planolites, Psilonichnus, Siphonichnus, Skolithos, Thalassinoides, Taenidium, and Trichichnus. Vertebrate-derived trace fossils include nine avian footprint ichnogenera (Aquatilavipes, Archaeornithipus, Ardeipeda, Aviadactyla, cf. Avipeda, cf. Fuscinapeda, cf. Ludicharadripodiscus, and two unnamed forms). A variety of shallow, circular to cylindrical pits and horizontal, singular to paired horizontal grooves preserved in concave epirelief are interpreted as avian feeding and foraging traces. These traces likely represent the activities of small to medium-sized shorebirds and waterbirds like those of living sandpipers, plovers, cranes, egrets, and herons. The pits and grooves are interpreted as foraging traces and occur interspersed with both avian trackways and invertebrate traces. The trace fossils occur preferentially in heterolithic successions with lenticular to flaser bedding, herringbone ripple stratification, and common reactivation surfaces, indicating that the study interval was deposited in a tidally influenced setting. Avian trackways, desiccation cracks, and common rooting indicate that the succession was prone to both subaqueous inundation and periodic subaerial exposure. We infer that the Tambak mixed vertebrate-invertebrate trace fossil association occurred on channel-margin intertidal flats in a tide-influenced estuarine setting. The occurrence of a moderately diverse avian footprint and foraging trace assemblage in the Tambak Member of the Tanjung Formation illustrates that shorebirds and waterbirds have been using wetlands in what is now Kalimantan for their food resources since at least the late Eocene.
Located in
Library
/
RBINS Staff Publications 2024
-
Baelen/Baelen : l’habitat germanique de Nereth. Etat d’avancement de l’étude du mobilier lithique (fouilles 2013-2021).
-
Located in
Library
/
RBINS Staff Publications 2023
-
Barcoding and traditional health practitioner perspectives are informative to monitor and conserve frogs and reptiles traded for traditional medicine in urban South Africa
-
Previous literature suggests that Indigenous cultural practices, specifically traditional medicine, are commonplace among urban communities contrary to the general conception that such practices are restricted to rural societies. We reviewed previous literature for records of herptiles (frog and reptile species) sold by traditional health practitioners in urban South Africa, then used visual confirmation surveys, DNA barcoding and folk taxonomy to identify the herptile species that were on sale. Additionally, we interviewed 11 IsiZulu and SePedi speaking traditional health practitioners to document details of the collection and pricing of herptile specimens along with the practitioners' views of current conservation measures for traditional medicine markets. The 34 herptile species recorded in previous literature on traditional medicine markets included endangered and non-native species. Spectrophotometry measurements of the DNA we extracted from the tissue of herptiles used in traditional medicine were an unreliable predictor of whether those extractions would be suitable for further experimental work. From our initial set of 111 tissue samples, 81 sequencing reactions were successful and 55 of those sequences had species-level matches to COI reference sequences on the NCBI GenBank and/or BOLD databases. Molecular identification revealed that traditional health practitioners correctly labelled 77% of the samples that we successfully identified with DNA barcoding in this study. Our mixed methodology approach is useful for conservation planning as it updates knowledge of animal use in Indigenous remedies and can accurately identify species of high conservation priority. Furthermore, this study highlights the possibility of collaborative conservation planning with traditional health practitioners.
Located in
Library
/
RBINS Staff Publications 2023 OA
-
Bats at the southern North Sea in 2017 & 2018
-
Located in
Library
/
RBINS Staff Publications 2019
-
Behavior and body size modulate the defense of toxin‑containing sawfly larvae against ants
-
Located in
Library
/
RBINS Staff Publications 2021
-
BICEpS Annual report 2019 – Reinforcing Belgian ICES People
-
The International Council for the Exploration of the Sea (ICES; French: Conseil International pour l'Exploration de la Mer, CIEM) is an intergovernmental marine science organization that brings together the efforts and knowledge of 20 Member States, bordering the North Atlantic and the Arctic Circumpolar Zone, on physical oceanography, marine ecosystems and fisheries management. Nowadays, more than 80 Belgian scientists are directly involved in the work of the 150 bodies and expert groups of ICES, which gather the expertise of more than 1500 scientists yearly, totalling up to 5000 scientists from over 700 marine institutes and organizations over the years. This important and often voluntary dedication of Belgian scientists to the work of ICES deserves more visibility among the Belgian scientific community itself and to policy makers.This is, among others, why the BICEpS initiative was launched in 2018. BICEpS general aim is to offer a platform to the Belgian ICES community to get to know each other, to improve collaboration and share information, and to promote ICES to the wider scientific community in Belgium. BICEpS Annual report 2019 presents the second year of activity of this initiative created to reinforce Belgian ICES people. The report targets marine scientists, marine managers and policy makers. It presents the results of the initiative so far. The report contains the list of Belgian ICES members in 2019 with their membership to the different ICES working groups, and the results of the second BICEpS Colloquium organised on 2 December 2019 and hosted by ILVO in Ghent (Summary of the sessions, abstracts of communications presented and list of participants). The abstracts of the colloquium are supplemented by a separate annex published online which assembles the PowerPoint presentations of the colloquium accessible at http://ices.dk/community/groups/Documents/BICEPS/BICEpS19-PPT-presentations.pdf This report is accessible on the ICES website at http://ices.dk/community/groups/Pages/BICEpS.aspx
Located in
Library
/
RBINS Staff Publications 2020
