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Abstract This chapter introduces the Oligochaeta annelids, here treated as a paraphyletic stem group of the class Clitellata separated from the Hirudinea, Acanthobdellida, and Branchiobdellida. It starts by considering the group in a phylogenetic and taxonomic framework, as well as in terms of geographical distribution and diversity. It then deals with the general biology of these worms in describing their anatomy, physiology, reproduction and life history. Ecological and behavioral aspects of Oligochaeta are next addressed through topics related to habitat distribution and limitations due to physiological constraints, feeding behavior, predators and parasites, competition, impact on the environment, and their use as organic pollution indicators. By the end of the chapter, the scientific study of the Oligochaeta is addressed via practical aspects such as collecting, culturing, and specimen preparation for identification.

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

Abstract Mercantour National Park (France) is recognized as a highly heterogeneous region with extremely varied geology, geomorphology and climatology, resulting in an exceptional biodiversity. From a hydrogeological point of view, it is also an area organized of small and discontinuous aquifers, their obligate groundwater fauna remaining absolutely unknown. This work explores the species richness of groundwaters in Mercantour National Park, using a sampling design at the catchment (six major valleys) and aquifer scales (aquifers in consolidated rocks and unconsolidated sediments). A major finding of this study is the discovery of 44 species restricted to groundwater, from which 43 are new to the Park and 10 are new to Science. Although a relatively small number of sites were sampled (53), the area may be considered as a new hotspot of groundwater biodiversity at the European level. The particular structure of the groundwater network, the high environmental heterogeneity of the region, and its Mediterranean position may explain such a high biodiversity. Species rarefaction curve showed that many species have yet to be discovered in groundwater of the Mercantour National Park. With more than 78% of species collected in the hyporheic zone, this study also highlights the importance of porous aquifers in sustaining groundwater biodiversity of mountainous regions. Key words: groundwater invertebrates, stygobionts, biodiversity hotspot, Mercantour National Park, hyporheic zone, spring. Résumé Biodiversité dans les eaux souterraines de montagne. Le Parc National du Mercantour: un ‘hotspot’ européen. Le Parc National du Mercantour est une région physiquement très hétérogène, avec des faciès géologiques, géomorphologiques et climatologiques extrêmement variés, à l’origine d’une biodiversité exceptionnelle. D'un point de vue hydrogéologique, son réseau souterrain est organisé en aquifères discontinus et de petite taille, dont la faune aquatique (stygobie) est aujourd’hui inconnue. Ce travail explore la richesse spécifique des eaux souterraines du Parc National du Mercantour, après la mise en œuvre d'un plan d'échantillonnage prenant en compte l'hétérogénéité environnementale à l’échelle du bassin versant (six vallées majeures) et de l'aquifère (aquifère fissuré ou poreux). Le premier fait marquant est la récolte de 44 espèces stygobies, 43 étant nouvelles pour le parc et 10 nouvelles pour la Science. Sur la base d’un nombre relativement faible de sites (53), cette zone peut être considérée comme un nouveau ‘hotspot’ de biodiversité des eaux souterraines à l'échelle européenne. La structure particulière du réseau hydrogéologique, l'hétérogénéité environnementale élevée, et la position méditerranéenne de cette région, pourraient expliquer une telle biodiversité. La courbe de raréfaction des espèces montre que nos connaissances sur le Mercantour sont néanmoins loin d'être complètes et que de nombreuses espèces restent encore à découvrir. Avec plus de 78 % des espèces récoltées dans la zone hyporhéique, ce travail souligne également le rôle des aquifères poreux, dans le maintien de la biodiversité des eaux souterraines de montagne. Mots-clés: invertébrés souterrains, stygobies, ‘hotspot’ de biodiversité, Parc National du Mercantour, zone hyporhéique, source.

In the framework of the Belgian BELSPO AGORA 3D and DIGIT03 programs, we have evaluated 3D digitising technologies with regards to the quality of the acquisition, the capacities and limitations of each technique and also the direct cost of the different 3D digitisation processes. It is on this latest topic that the paper is focused. In order to evaluate the cost of 3D digitisation, we considered the time for the digitisation, cost of the equipment and cost of the staff. Our preliminary results show that the real cost by specimen depends on the amount of specimens to digitise. Techniques that appear to be low-cost can be the most expensive in the framework of massive digitization programs, whilst more expensive equipment can be more efficient in the long term. Therefore low-cost equipment is mainly recommended for occasional digitisation or small series of digitisations.

Recent developments in remote sensing techniques provide powerful tools for geomorphological studies. The geometric and kinematic characterization of landslides are key factors in understanding the mechanisms of movement. The purpose of this publication is to show the potential of digital photogrammetry in the spatiotemporal study of landslides in urban areas. The case study focuses on the landslide of El Biar in Algiers. Comparison of digital elevation models generated following an established methodology shows the morphological evolution of the site. Orthophotos are used to measure surface displacements. The analysis of horizontal displacements between 1995 and 2007 shows that the landslide of El Biar can be divided into two zones: a peripheral zone moving at an average speed of about 5 cm per year and a central zone moving at an average speed of about 10 cm per year. Comparing the results with those obtained by traditional survey methods shows a remarkable consistency, thus validating the techniques used. This study demonstrates that digital photogrammetry, when combined with geological and geotechnical data, can improve the characterization and understanding of landslides mechanisms, and thus help defining mitigation solutions.

Efforts to identify Paleolithic dogs or incipient dogs have been based mainly on examination of complete or nearly complete crania. Complete skulls are, however, very rare in the archaeological record. Because canid mandible are far more frequently found in Pleistocene assemblages, the objective of this study is to investigate whether it is possible to differentiate these jaws by metric and osteomorphological methods in two morphotypes: Paleolithic dogs and Pleistocene wolves. This paper is mainly based on the very rich canid assemblage from the Gravettian Předmostí site in the Czech Republic, but also includes a few mandible from several other European Paleolithic sites. This study provides additional evidence of the existence at Předmostí of the two canid morphotypes. The metric data indicate that the mandible of the Paleolithic dogs are shorter than those from Pleistocene wolves in all tested measurements of length, and the carnassial crown length is shorter in Paleolithic dogs compared with the length of this tooth in Pleistocene wolves. Furthermore, in eight of nine indexes, the Paleolithic dogs differ significantly from the Pleistocene wolves. The mandible of Paleolithic dogs differ also in non-metric features from the Pleistocene wolves: they present a high frequency of crowded premolars and backwards-oriented apex of the coronoid. This paper furthermore confirms that Paleolithic dogs occur at two late Upper Paleolithic sites (Eliseevichi, Verholenskaya) where previous studies had indicated their presence. In addition, we document the presence of Paleolithic dogs at another Gravettian site, Kostenki-8.