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Point source contaminations origin from historic or current activities and occur in a variety of forms, extents and contaminants involved (e.g. landfills, industrial facilities, storage tanks, disposal of hazardous waste). Point source contaminations may pose risks to human health and the environment; it is therefore important to develop/improve current methodologies to assess the migration potential of contaminants in groundwater. Groundwater quality monitoring around contaminated sites is typically done by sampling piezometers. Modelling approaches can help to predict the spatial and temporal evolution of contamination plumes, design remediation strategies and assess health and environmental risks. Reactive transport models can potentially improve the prediction of contaminant routes, as they explicitly account for changing geochemical environments and chemical reactions during transport. In spite of recent advances, real-world applications remain scarce as these require large numbers of site-specific parameters. The aim of the RESPONSE project is to improve the use of reactive transport models that simulate the fate of inorganic and organic contaminants in soils and groundwater. More specifically, this project aims to (1) identify the minimum amount of site-specific parameters needed to predict reactive transport of inorganic pollutants (e.g. heavy metals) and (2) improve/simplify the modelling of transport of xenobiotic organic contaminants (XOC, e.g. hydrocarbons and pesticides). The transport of XOCs is particularly complex to model due to the effects and zonation of microbial activity at the plume fringe in polluted aquifers. The RESPONSE project focusses on typical groundwater pollution problems encountered around old municipal landfill sites and cemeteries. Municipal landfills can still release hazardous pollutants such as heavy metals and XOCs, even if they are covered by fresh ground layers after abandonment. Cemeteries can be considered a special case of landfill, releasing various compounds to the environment such as arsenic, mercury, bacteria, viruses and herbicides. Both location types are potential point sources for mixed groundwater pollution, typically including high concentrations of dissolved organic carbon (DOC), heavy metals and XOCs. The methodology in this project involves both experimental and modelling aspects. During the first screening stage, groundwater samples were collected from shallow piezometers at fifteen contaminated sites across Belgium (municipal landfills and cemeteries). Also, an improved reactive transport model is built based on HYDRUS1D-MODFLOW-PHREEQC to explicitly account for the dynamic behaviour of chemical conditions at the soil-ground water interface. Next, based on laboratory analyses, three case-study sites will be selected for further modelling and testing.

1. Background Tsunami deposits provide information on the long-term frequency-magnitude patterns of events, which may not be covered by the historical and instrumental record. Such information is crucial for the assessment of coastal hazards and mitigation measures against the loss of life and assets. In order to identify tsunami deposits in the coastal sedimentary record and to infer tsunami characteristics, a wide range of proxies has been established based on studies of recent tsunami deposits. Microfossils (e.g. foraminifera, ostracods, diatoms) are often used to recognize tsunami deposits, and to differentiate them from those of other processes. In terms of foraminifera, tsunami deposits mostly contain allochthonous associations dominated by benthic intertidal to inner shelf taxa. Specimens may originate from outer shelf to bathyal depths; even planktonic forms may occur. Furthermore, changes in test numbers, taphonomy, size or adult/juvenile ratios compared to background sedimentation are common (Pilarczyk et al., 2014; Engel et al., 2016). However, dissolution of microfossils often prevent identification and diminish their value as a proxy (Yawsangratt et al., 2012). 2. Study goals and concept To address the problem of post-depositional alteration of microfossil associations in tsunami deposits, high-throughput metagenomic sequencing techniques are applied by the GEN-EX project to identify marine organisms in onshore sand layers based on their DNA remains. Metagenomics (or environmental genomics) is related to sequencing DNA directly from the environmental samples, where the genetic material may have been preserved in sedimentary records covering tens of thousands of years. Metagenomics is an emerging technique in environmental research and is used to characterize the diversity of bacterial communities but also higher organisms such as animals, plants and fungi of recent and ancient origin in a variety of settings, including ice, lake sediments, soils, cave deposits, and various types of surface waters. Metagenomics can also be used to detect cryptic diversity, ultimately providing more accurate estimates of biodiversity (Pedersen et al., 2015). Among the broad range of organisms, foraminifera (single-celled protists) show a water depth-related zonation in subtidal environments, and are the first to have been identified successfully in palaeo- tsunami deposits by their DNA (SzczuciĔski et al., 2016). The main objectives of GEN-EX include: quantifying the relationship between water depth and the distribution of different foraminiferal taxa where known tsunami deposits are present, using a comparative classic micropalaeontological and metagenomic approach; assessing the potential (based on both approaches) for identifying key indicator species in tsunami deposits in different coastal settings; and establishing how metagenomic approaches can contribute to the differentiation between storm and tsunami deposits. 3. DNA extraction DNA will be analysed in two types of material – modern extant foraminifera and sediments (tsunami deposits and adjacent layers). DNA extracted from single foraminiferal specimens will be followed by whole genome amplification to obtain sufficient DNA concentrations. Either part of the nuclear 18S rRNA region or the mitochondrial genome (mtDNA) will be amplified, before high-throughput sequencing of the amplicons. Sequences will be edited and aligned, and their identity verified by BLAST (Altschul et al., 1990) searches in Genbank and the Forambarcoding project (http://forambarcoding.unige.ch). A project-specific database of 18S and mtDNA data of the identified recent foraminifera will be constructed. Sampling of tsunami deposits and DNA extraction follows the protocol of SzczuciĔski et al. (2016). Suitable primers will be developed from our reference database of recent foraminifera to amplify overlapping short fragments of 18S or mtDNA of the target species. Amplicon concentration will be quantified and prepared for high-throughput sequencing. Sequence data will be analysed with different bioinformatics pipelines (e.g. QIIME), including quality control, removal of barcodes and adaptors, identification and removal of chimeric and redundant sequences, and comparisons with our own and open access databases of 18S data for defining Operational Taxonomic Units with 95% and 97% similarity cut-offs. 4. Study area One of the study areas, where the eDNA approach is applied, are the Shetland Islands, exposed to the mega-tsunami triggered by the early Holocene Storegga submarine slide off the coast of Norway. Sediment run-up of more than 25 m left a distinct landward-thinning sand layer with an erosive lower contact, large rip-up clasts, fining-upward sequences and marine diatoms in near-shore lakes and coastal peat lowlands. In addition to sediments associated with the Storegga tsunami, two younger tsunami deposits dated to c. 5 and 1.5 ka (Bondevik et al., 2005) are investigated. Sampling for the planned foraminiferal analyses and eDNA extraction of the deposits and their source area, comprising along the beach and subtidal area to the central shelf area is scheduled for the second half of March 2018. 5. Acknowledgements Funding is kindly provided by a BELSPO BRAIN-be pioneer grant (BR/175/PI/GEN-EX). 6. References Altschul, S.F., Gish, W., Miller, W., Myers, E.W. & Lipman, D.J., 1990. Basic local alignment search tool. Journal of Molecular Biology, 215, 403–410. Bondevik, S., Mangerud, J., Dawson, S., Dawson, A. & Lohne, Ø., 2005. Evidence for three North Sea tsunamis at the Shetland Islands between 8000 and 1500 years ago. Quaternary Science Reviews, 24, 1757–1775. Engel, M., Oetjen, J., May, S.M. & Brückner, H., 2016. Tsunami deposits of the Caribbean – Towards an improved coastal hazard assessment. Earth-Science Reviews, 163, 260–296. Pedersen, M.W., Overballe-Petersen, S., Ermini, L., Sarkissian, C.D., Haile, J., Hellstrom, M., Spens, J., Thomsen, P.F., Bohmann, K., Cappellini, E., Bærholm Schnell, I., Wales, N.A., Carøe, C., Campos, P.F., Schmidt, A.M.Z., Gilbert, M.T.P., Hansen, A.J., Orlando, L. & Willerslev, E., 2015. Ancient and modern environmental DNA. Philosophical Transactions of the Royal Society B, 370, 20130383. Pilarczyk, J.E., Dura, T., Horton, B.P., Engelhart, S.E., Kemp, A.C. & Sawai, Y., 2014. Microfossils in coastal environments as indicators of paleo-earthquakes, tsunamis and storms. Palaeogeography, Palaeoclimatology, Palaeoecology, 413, 144–157. SzczuciĔski, W., Pawłowska, J., Lejzerowicz, F., Nishimura, Y., KokociĔski, M., Majewski, W., Nakamura, Y. & Pawlowski, J., 2016. Ancient sedimentary DNA reveals past tsunami deposits. Marine Geology, 381, 29–33. Yawsangratt, S., SzczuciĔski, W., Chaimanee, N., Chatprasert, S., Majewski, W. & Lorenc, S., 2012. Evidence of probable paleotsunami deposits on Kho Khao Island, Phang Nga Province, Thailand. Natural Hazards, 63, 151–163.

Les plus anciens crocodiliens (Crocodylia) d’Asie ne sont représentés jusqu’à présent que par des alligatoroïdes et des planocraniidés. Bien que les crocodyloïdes ne soient pas connus avec certitude avant l’Éocène supérieur, l’hypothèse a été émise que des crocodyloïdes basaux de type Asiatosuchus étaient originaires d’Asie avant la fin du Paléocène. Nous décrivons ici un nouveau crocodyloïde fossile provenant du Paléocène inférieur du Bassin de Qianshan, province d’Anhui, Chine. Le crâne et le fragment de mâchoire inférieure associé présentent plusieurs caractéristiques typiques de crocodiliens juvéniles. Ils présentent également une combinaison de caractères non observés dans aucun autre taxon, ce qui justifie l’érection d’une nouvelle espèce et d’un nouveau genre. Les affinités phylogénétiques sont testées dans des analyses basées sur deux matrices de caractères récentes d’Eusuchia. Pour évaluer l’effet des caractéristiques juvéniles sur le résultat des analyses phylogénétiques, des spécimens juvéniles des crocodiliens actuels Alligator mississippiensis et Crocodylus niloticus ont été analysés de la même manière, montrant que l’effet de leur stade ontogénétique sur leur position dans l’arbre est minime. Nos analyses indiquent que le nouveau taxon de Qianshan occupe une position basale au sein des Crocodyloidea. La présence de ces derniers en Asie est donc reculée au Paléocène inférieur, soit 15 à 20 millions d’années plus tôt que ce que l’on pensait auparavant. De plus, nos résultats corroborent les hypothèses précédentes d’une route de dispersion paléocène des crocodyloïdes de type Asiatosuchus de l’Asie vers l’Europe.

Les plus anciens crocodiliens (Crocodylia) d’Asie ne sont représentés jusqu’à présent que par des alligatoroïdes et des planocraniidés. Bien que les crocodyloïdes ne soient pas connus avec certitude avant l’Éocène supérieur, l’hypothèse a été émise que des crocodyloïdes basaux de type Asiatosuchus étaient originaires d’Asie avant la fin du Paléocène. Nous décrivons ici un nouveau crocodyloïde fossile provenant du Paléocène inférieur du Bassin de Qianshan, province d’Anhui, Chine. Le crâne et le fragment de mâchoire inférieure associé présentent plusieurs caractéristiques typiques de crocodiliens juvéniles. Ils présentent également une combinaison de caractères non observés dans aucun autre taxon, ce qui justifie l’érection d’une nouvelle espèce et d’un nouveau genre. Les affinités phylogénétiques sont testées dans des analyses basées sur deux matrices de caractères récentes d’Eusuchia. Pour évaluer l’effet des caractéristiques juvéniles sur le résultat des analyses phylogénétiques, des spécimens juvéniles des crocodiliens actuels Alligator mississippiensis et Crocodylus niloticus ont été analysés de la même manière, montrant que l’effet de leur stade ontogénétique sur leur position dans l’arbre est minime. Nos analyses indiquent que le nouveau taxon de Qianshan occupe une position basale au sein des Crocodyloidea. La présence de ces derniers en Asie est donc reculée au Paléocène inférieur, soit 15 à 20 millions d’années plus tôt que ce que l’on pensait auparavant. De plus, nos résultats corroborent les hypothèses précédentes d’une route de dispersion paléocène des crocodyloïdes de type Asiatosuchus de l’Asie vers l’Europe.