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  • The evolution of infrastructure networks such as roads and streets are of utmost importance to understand the evolution of urban systems. However, datasets describing these spatial objects are rare and sparse. The database presented here represents the road network at the french national level described in the historical map of Cassini in the 18th century. The digitalization of this historical map is based on a collaborative platform methodology that we describe in detail. These data can be used for a variety of interdisciplinary studies, covering multiple spatial resolutions and ranging from history, geography, urban economics to the science of network. (2015-01-15)

  • As part of the Sélune observatory, pilot stations have been set up along the main course of the Sélune, distributed from upstream to downstream of the hydroelectric dams. Three stations are located in the former reservoirs of the dams, while the other two, known as the reference stations, are outside the area of influence of the former dams (one downstream and the other upstream). At these stations, aquatic biocenoses (including benthic macroinvertebrates, biofilms, macrophytes, etc.) are monitored. 2 sampling campaigns (spring and autumn) for benthic macroinvertebrates (bmi) have been carried out since September 2014. During each campaign, 2 sampling protocols are implemented: - in accordance with standard NF T90-333, which enables the calculation of the IBG-DCE and I2M2 (‘SURBER’) - via artificial substrates immersed for 1 month (‘SUBART’), in order to focus on measuring the ‘effect of dams’. The protocol is described in: Piscart C., Moreteau, J.C., Beisel J.N. (2006). Monitoring changes in freshwater macroinvertebrate communities along a salinity gradient using artificial substrates. Environmental Monitoring and Assessment 116: 529-542. This layer details the benthic macroinvertebrate taxa and their abundance obtained after analysis (according to standard NF T90-388). These data are distributed by campaign and by sector. Taxa presenting all the morphological criteria clearly visible and characteristic allowing the exactitude of their determination and an irreproachable state of conservation are integrated into the reference collection of the Sélune Observatory. This collection can be consulted on request (see contact point). Taxon determination is based on version v17 of the TAXREF reference.

  • Microbial communities play a major role in the functioning of ecosystems: they are at the base of the food chain (primary production) and participate in the degradation of organic matter. These communities are also known to respond rapidly to environmental changes. Like macro-invertebrates, they can be used as ecological indicators. Benthic diatoms are the main photosynthetic organisms in this biological community. The relative abundance of the different species is used to calculate an environmental quality index (EQI). Major differences in communities between the upstream and downstream zones were observed when the dams were in place. These differences will change once the dams are removed. As part of the Sélune observatory, pilot stations have been set up along the main course of the Sélune, distributed from upstream to downstream of the hydroelectric dams. Three stations are located in the former reservoirs of the dams, while the other two, known as the reference stations, are outside the area of influence of the former dams (one downstream and the other upstream). At these stations, aquatic biocenoses (including benthic macroinvertebrates, biofilms, macrophytes, etc.) are monitored. Since September 2014, the stations are ideally sampled every month from April to October (7 annual surveys) using artificial substrates (glass slides placed in the water). In addition to the diatom survey (floristic list, IBD calculation), the chlorophyll-a concentration is measured. During each campaign, an INRAe experimental sampling protocol is implemented. This protocol involves the immersion (1 month) of glass slides, in situ measurement of chlorophyll-a concentration via BentoTorch and then collection of the biofilm on these glass slides. The biofilm is conditioned in (1) 99.9% ethanol for determination of IBDs and floristic lists (outsourced service, based on standard NF T90-354) and (2) mineral water for measurement of chlorophyll-a concentration using a spectrometer. Taxon identification is based on version v17 of the TAXREF reference.

  • Microbial communities play a major role in the functioning of ecosystems: they are at the base of the food chain (primary production) and participate in the degradation of organic matter. These communities are also known to respond rapidly to environmental changes. Like macro-invertebrates, they can be used as ecological indicators. Benthic diatoms are the main photosynthetic organisms in this biological community. The relative abundance of the various species is used to calculate an environmental quality index (EQI). Major differences in communities between the upstream and downstream zones were observed when the dams were in place. These differences will change once the dams are removed. As part of the Sélune Observatory, the stations are sampled every month from April to October (7 annual surveys) using artificial substrates (glass slides placed in the water). In addition to the diatom survey (floristic list, IBD calculation), the chlorophyll a concentration is measured. This layer gives the IBD and EQR (normalised) index value for a station during a campaign.

  • As part of the Sélune observatory, pilot stations have been set up along the main course of the Sélune, distributed from upstream to downstream of the hydroelectric dams. Three stations are located in the former reservoirs of the dams, while the other two, known as the reference stations, are outside the area of influence of the former dams (one downstream and the other upstream). At these stations, aquatic biocenoses (including benthic macroinvertebrates, biofilms, macrophytes, etc.) are monitored. At each of these stations, benthic macroinvertebrates (bmi) have been sampled regularly, in spring and autumn, since September 2014 and in accordance with standard NF T 90-333. The fauna inventories obtained after determination can thus be used to calculate biotic indices such as the IBG-DCE and the I2M2. In addition, samples were taken using artificial substrates immersed for 1 month, in order to focus on measuring the ‘dam effect’. The protocol is described in: Piscart C., Moreteau, J.C., Beisel J.N. (2006). Monitoring changes in freshwater macroinvertebrate communities along a salinity gradient using artificial substrates. Environmental Monitoring and Assessment 116: 529-542. This layer gives the results obtained for the IBG-DCE and I2M2 biotic indices with the associated parameters (diversity, variety, etc.), as well as the number of samples taken (‘effort’ column). Finally, the layer contains the output from the ‘ODInvertebres’ diagnostic tool for benthic invertebrates, which aims to identify the most likely anthropogenic pressures causing changes in ecological quality (6 probability values for physico-chemical water quality and 6 others relating to hydromorphology or land use in the catchment area). Reference on ‘ODInvertebres’ : Mondy, C. P., & Usseglio-Polatera P. Using conditional tree forests and life history traits to assess specific risks of stream degradation under multiple pressure scenario. Science of the Total Environment 461 (2013): 750-760. The genus Baetis cited in the fauna lists refers to the genus ‘Baetis lato sensu’ according to the SANDRE nomenclature (Sandre code: 9794). Taxa presenting all of the clearly visible and characteristic morphological criteria enabling them to be accurately identified and in an irreproachable state of conservation are included in the Observatoire Sélune's reference collection. This can be consulted on request (see point of contact).

  • Microbial communities play a major role in the functioning of ecosystems: they are at the base of the food chain (primary production) and participate in the degradation of organic matter. These communities are also known to respond rapidly to environmental changes. Like macro-invertebrates, they can be used as ecological indicators. Benthic diatoms are the main photosynthetic organisms in this biological community. The relative abundance of the different species is used to calculate an environmental quality index (EQI). Major differences in communities between the upstream and downstream zones were observed when the dams were in place. These differences will change once the dams are removed. As part of the Sélune observatory, pilot stations have been set up along the main course of the Sélune, distributed from upstream to downstream of the hydroelectric dams. Three stations are located in the former reservoirs of the dams, while the other two, known as the reference stations, are outside the area of influence of the former dams (one downstream and the other upstream). At these stations, aquatic biocenoses (including benthic macroinvertebrates, biofilms, macrophytes, etc.) are monitored. Since September 2014, the stations are ideally sampled every month from April to October (7 annual surveys) using artificial substrates (glass slides placed in the water). In addition to the diatom survey (floristic list, IBD calculation), the chlorophyll-a concentration is measured. During each campaign, an INRAe experimental sampling protocol is implemented. This protocol involves the immersion (1 month) of glass slides, an in situ measurement of the chlorophyll-a concentration via BentoTorch and then the collection of the biofilm on these glass slides. The biofilm is conditioned in (1) 99.9% ethanol to determine IBDs and floristic lists (outsourced service, based on standard NF T90-354) and (2) mineral water to measure chlorophyll-a concentration using a spectrometer. NB: the year 2023 is not covered in terms of measuring chlorophyll-a concentration via spectrometry due to a problem with the low-temperature storage of samples. This dataset provides measurements of the average daily concentration of chlorophyll-a and pheopigment in µg/cm2/day.

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    Groundwater comprises approximately 30 percent of the Earth’s total freshwater, serving as a vital resource for both humans and ecosystems. As an essential source of drinking water for humans and sustenance for vegetation, groundwater plays a key role in the terrestrial water cycle. It acts as a buffer, enabling adaptation to climate variability and extreme events like floods and droughts. Therefore, understanding groundwater storage is important for both ecological and15 societal reasons.

  • Résumé Distribution géographique de l'ajonc Ulex europaeus à l’échelle mondiale au format Darwin Core. Les points de coordonnées sont en degrés décimaux (latitude, longitude), ils correspondant à l’existence avérée d’un individu d'Ulex europaeus entre 1950 et 2018. Le jeu de données est une compilation de plusieurs sources, banques de données en ligne (dont GBIF, iNaturalist), articles scientifiques, communications personnelles et prospection par les auteurs (sur le terrain ou par recherche visuelle en ligne). Les données collectées ont été nettoyées, vérifiées, et les doublons éliminés. Tous les pays ou régions ayant référencé de l’ajonc sont répertoriés, sauf la zone native (Europe). Le jeu de données obtenu comprend 14053 occurrences. Les points géo-localisés sont classifiés selon les limites administratives des pays ou îles dans lesquels ils sont situés. Pour l'Europe, se reporter à la base GBIF. Qualité Les données ont été vérifiées de plusieurs manières : élimination des doublons, vérifications visuelles sur images géo-localisées (pour les données issues des sciences citoyennes), élimination des points aberrants (par exemple ceux localisés dans la mer), ou non-pertinents (dans des Muséums, centroïdes de régions administratives ou d’objets vectoriels de grande taille…). Pour les données retenues, la précision maximale a été recherchée en recoupant de multiples informations (littératures, observations, communications personnelle, images géolocalisées). La précision des géolocalisations obtenues est inférieure à 100 mètres dans les deux-tiers des points, inférieur au km pour les trois quart des points. Programme ANR MARIS : Management and risk analysis of an invading plant species (ulex europaeus (L.): how socio-ecological niche with population dynamics modelling under a wide range of climates can help. ANR reference : ANR-14-CE03-0007

  • Superposition de la délimitation des Bassins Versants de Bretagne avec l'indice de végétation NDVI découpé sur la ville de Rennes. Les Bassins Versants de l'étude CSEB résume la localisation et la délimitation de l'ensemble des bassins versants présent en Bretagne. Cette donnée est disponible en libre service sur GéoBretagne. Le NDVI calculé sur Rennes est basé sur un image Sentinel-2 récupéré sur SentinelHub.

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    Couche vectorielle ponctuelle de localisation du réseau de capteurs de température et de stations météorologiques de Rennes et des communes périphériques (Rennes Urban Network). Capteurs de température et d'humidité: RisingHF connectés par LoRaWAN Stations météorologiques (températures, humidité, vent, précipitations...) connectées par Internet (Raspberry). Parfois pour un point: 2 données renseignées dans la table attributaire qui correspondent à une station et un capteur (les stations ont été doublées d'un capteur afin de valider la concordance entre les deux). Installés depuis le 1er avril 2021 sur l'ensemble du territoire Villes: Rennes, Cesson-Sévigné, Saint-Jacques-de-la-Lande, Saint-Grégoire, Vern-sur-Seiche, Le-Rheu, Pacé, Betton, Chantepie, La-Mézière, Thorigné-Fouillard, Vezin-Le-Coquet, Melesse, l'Hermitage, La-Chapelle-des-Fougeretz, Montgermont,Chevaigné