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Belgium is well-known for its diverse collection of built heritage, visited every year by millions of people. Because of its cultural and economic importance, conservation is a priority at both federal and regional levels. Monuments may suffer from structural instabilities related to industrial and urban development, such as groundwater extraction, mining and excavation activities. Adequate protection and preservation requires an integrated analysis of environmental, architectural and historical parameters. The aim of the GEPATAR project is to create an online interactive geo-information tool that integrates information about Belgian heritage buildings and the occurrence of ground movements. The toolbox will allow the user to view and be informed about buildings potentially at risk due to differential ground movements and thus help improving the management of built patrimony. Countrywide deformation maps spanning nearly 25 years were produced by applying advanced multi-temporal InSAR techniques to time-series of SAR data. We used StaMPS (Stanford Method for Persistent Scatterers; Hooper et al. 2012) to process ERS-1/2 and Envisat archive data and MSBAS (Multidimensional Small Baseline Subsets; Samsonov & d’Oreye 2012) to combine both ascending and descending tracks of Sentinel-1. High-resolution deformation maps of selected urban centres were obtained by processing VHR SAR data (TerraSAR-X and CosmoSkyMed). Within the GEPATAR toolbox, the country-scale deformation maps are integrated with other geo-data layers such as geology, land-use and the location of the built heritage; feature-based data fusion techniques and decision rules based on geomechanical expertise are combined to create ground movement risk maps. At the local scale the fusion process is more complicated due to the inclusion of non-spatial datasets, such as photographic and historical surveys, architectural and geotechnical data; at this scale decision rules are provided by engineering and architectural expertise. The output risk maps will be regularly updated with the availability of new SAR acquisitions. Some selected case-studies will be investigated at high resolution by means of on-site monitoring techniques as well as stability analysis to evaluate the applied approaches.

ABSTRACT Although recognized as an outstanding hotspot of biodiversity for both flora and fauna, the Mercantour massif remains almost totally unexplored for its groundwater fauna. This work reports the first overview on groundwater oligochaete assemblages of the “Parc du Mercantour” after a standardized exploration of both consolidated (fractured massif) and unconsolidated (porous) aquifers. About 40 species of oligochaetes were found in 49 stations representative of the main hydrogeological basins of the “Parc du Mercantour”, from both spring and hyporheic zone habitats. Five stygobiont species are identified, probably all new to science, of which two species are formally described, Aberrantidrilus stephaniae n. gen., n. sp. (Naididae, Phallodrilinae) and Marionina sambugarae n. sp., a species belonging to the widespread Marionina argentea species complex (Enchytraeidae). As a result, the genus Abyssidrilus Erséus, 1992 is now restricted to its marine, abyssal species. A dozen of species can be considered as stygophiles. Most stygobiont species are recorded from hyporheic habitats, and stygophiles have a more balanced distribution between both kinds of habitats. The nearly absence of stygoxene species from the hyporheic zone suggests that this habitat is less affected by the epigean environment than springs. The dominance of enchytraeids among the groundwater oligochaete fauna is here confirmed, and the lumbriculid genus Trichodrilus is also a characteristic faunistic element of the underground freshwater oligochaete communities. Lastly, the possibility that Aberrantidrilus cuspis n. comb. sensu Sambugar et al. (1999) is a complex of cryptic species is discussed in the framework of recent progress in the knowledge of groundwater biodiversity. Key words: Aquatic Clitellata, Oligochaeta, groundwater, Mercantour, new species, Aberrantidrilus n. gen., Marionina, Abyssidrilus RESUME Oligochètes (Annelida, Clitellata) des eaux souterraines du Parc du Mercantour (France), avec description d’un nouveau genre et de deux nouvelles espèces stygobiontes. Bien qu’il soit reconnu comme un remarquable point chaud de biodiversité pour sa flore et sa faune, le massif du Mercantour reste presque totalement inexploré quant à sa faune souterraine. Ce travail rapporte le premier aperçu des assemblages d’oligochètes des eaux souterraines du « Parc du Mercantour », suivant une exploration standardisée des aquifères consolidés (massif fracturé) et non consolidés (poreux). Environ 40 espèces d’oligochètes ont été trouvées dans 49 stations représentatives des principaux bassins hydrogéographiques du « Parc du Mercantour », ainsi que des sources et de la zone hyporhéique. Cinq espèces stygobiontes ont été identifiées, probablement toutes nouvelles pour la Science, parmi lesquelles deux ont été formellement décrites, Aberrantidrilus stephaniae n. gen., n. sp. (Naididae, Phallodrilinae) et Marionina sambugarae n. sp., une espèce appartenant au complexe d’espèces Marionina argentea (Enchytraeidae) à large répartition. Il en résulte que le genre Abyssidrilus Erséus, 1992 est maintenant restreint à ses espèces marines et abyssales. Une douzaine d’espèces peuvent être considérées comme stygophiles. La plupart des espèces stygobiontes proviennent des habitats hyporhéiques tandis que les stygophiles se répartissent de façon plus équilibrée entre les deux types d’habitats. La quasi absence d’espèces stygoxènes dans la zone hyporhéique suggère que cet habitat est moins affecté par l’environnement épigé que les sources. La dominance des enchytréides au sein de la faune des oligochètes des eaux souterraines est ici confirmée, ainsi que le genre Trichodrilus en tant qu’élément faunistique le plus caractéristique des communautés des oligochètes des eaux douces souterraines. Enfin, la possibilité qu’Aberrantidrilus cuspis n. comb. sensu Sambugar et al. (1999) soit un complexe d’espèces cryptiques est discutée dans le cadre des progrès récents dans la connaissance de la biodiversité des eaux souterraines. Mots clés : Clitellata aquatiques, Oligochètes, eaux souterraines, Mercantour, nouvelles espèces, Aberrantidrilus n. gen., Marionina

The skull roof growth of Arabosteus variabilis (Acanthothoraci), from the Pragian-Early Emsian of Saudi Arabia is studied on the basis of well-preserved growth lines on the dermal plates. A clear tendency towards growth in length, i.e. allometry in length, can be observed for all studied skull roof plates of Arabosteus variabilis as well as for the skull roof in general. Each studied plate displays particular growth shaping the skull roof according to its position in the skull roof pattern, e.g., the preorbital plate controls the shape of the part of the orbit and the nuchal plate retains the relative proportions in the skull roof during growth.