French Ardennes Research Articles

Paleoserological detection of Coronavirus antigens in dental calculus of human remains dating from the beginning of the 19th century, French Ardennes.

Vanishing viral RNA restricts our ability to detect ancient pathogens, so, we used paleo serological approaches to trace the dynamics of the Coronavirus in ancient populations. We investigated 10 ancient dental calculus samples collected from a cemetery dated to the beginning of the 19th century and excavated in Charleville-Mézières. After paleoserum samples were extracted from dental calculus, paleoserology using mini-line-blot incorporating one alpha-Coronavirus (Coronavirus 229 E) and two beta-Coronavirus (Coronavirus OC 43, SARS-CoV-2) antigens and controls was completed by an automated Western blotting assay. Once appropriate controls had validated the data, mini-line-blot detected antibodies against the two beta-Coronavirus antigens in individuals US1300 and US1339, automated Western blotting confirming one beta-Coronavirus antigen for individual US1300 and an additional individual US1326. Combing mini-line blot and automated Western blot assays made it possible to detect immunoreactive immunoglobulin tracing circulation of Coronavirus in France at the very beginning of the 19th century.

Co-infection of Ticks: The Rule Rather Than the Exception.

IntroductionTicks are the most common arthropod vectors of both human and animal diseases in Europe, and the Ixodes ricinus tick species is able to transmit a large number of bacteria, viruses and parasites. Ticks may also be co-infected with several pathogens, with a subsequent high likelihood of co-transmission to humans or animals. However few data exist regarding co-infection prevalences, and these studies only focus on certain well-known pathogens. In addition to pathogens, ticks also carry symbionts that may play important roles in tick biology, and could interfere with pathogen maintenance and transmission. In this study we evaluated the prevalence of 38 pathogens and four symbionts and their co-infection levels as well as possible interactions between pathogens, or between pathogens and symbionts.Methodology/principal findingsA total of 267 Ixodes ricinus female specimens were collected in the French Ardennes and analyzed by high-throughput real-time PCR for the presence of 37 pathogens (bacteria and parasites), by rRT-PCR to detect the presence of Tick-Borne encephalitis virus (TBEV) and by nested PCR to detect four symbionts. Possible multipartite interactions between pathogens, or between pathogens and symbionts were statistically evaluated. Among the infected ticks, 45% were co-infected, and carried up to five different pathogens. When adding symbiont prevalences, all ticks were infected by at least one microorganism, and up to eight microorganisms were identified in the same tick. When considering possible interactions between pathogens, the results suggested a strong association between Borrelia garinii and B. afzelii, whereas there were no significant interactions between symbionts and pathogens.Conclusion/significanceOur study reveals high pathogen co-infection rates in ticks, raising questions about possible co-transmission of these agents to humans or animals, and their consequences to human and animal health. We also demonstrated high prevalence rates of symbionts co-existing with pathogens, opening new avenues of enquiry regarding their effects on pathogen transmission and vector competence.

Diversity of viruses in Ixodes ricinus, and characterization of a neurotropic strain of Eyach virus.

Ticks transmit more pathogens—including bacteria, parasites and viruses—than any other arthropod vector. Although the epidemiological status of many tick-borne bacteria is very well characterized, tick-borne viruses are still relatively under-studied. Recently, several novel tick-borne viruses have been isolated from human febrile illnesses following tick bites, indicating the existence of other potential new and unknown tick-borne viruses. We used high-throughput sequencing to analyse the virome of Ixodes ricinus, the main vector of tick-borne pathogens in Europe. The majority of collected viral sequences were assigned to two potentially novel Nairovirus and Phlebovirus viruses, with prevalence rates ranging from 3.95% to 23.88% in adults and estimated to be between 0.14% and 72.16% in nymphs. These viruses could not be isolated from the brains of inoculated immunocompromised mice, perhaps indicating that they are unable to infect vertebrates. Within the I. ricinus virome, we also identified contigs with >90% identity to the known Eyach virus. Initially isolated in the 1980s, this virus was indirectly associated with human disease, but had never been extensively studied. Eyach virus prevalence varied between 0.07% and 5.26% in ticks from the French Ardennes and Alsace regions. Eyach virus was successfully isolated following intracerebral inoculation of immunocompromised mice with Eyach virus-positive tick extracts. This virus was also able to multiply and persist in the blood of immunocompetent mice inoculated by intraperitoneal injection, and caused brain infections in three of nine juveniles, without any obvious deleterious effects.

Patrimoine industriel et identité territoriale dans les Ardennes

La notion de patrimoine industriel, tardivement imposee en France, interesse le dialogue engage entre geographes et amenageurs d’un cote et economistes de l’autre, sur les liens entre patrimoine et territoire. En effet, ces disciplines sont concernees a la fois par la genese de ce patrimoine a l’occasion de processus de desindustrialisation ou de reconversion industrielle, par les modalites de son identification et de son appropriation qui en font un marqueur territorial et par les problemes de conservation et de valorisation qu’il pose en fonction de ses caracteres specifiques.Nous avons choisi d’illustrer cette problematique par le cas des Ardennes industrielles. La vallee de la Meuse de Mouzon a Givet dessine un « arc industriel » a forte personnalite caracterisee par la preponderance quasi-exclusive de la metallurgie, particulierement de la fonderie de fonte, de la forge et de l’estampage. Cette industrie ardennaise a ete severement frappee a partir de 1975 par un mouvement de desindustrialisation qui a laisse de tres nombreuses friches industrielles. Il reste ainsi un riche heritage, tres visible par sa concentration spatiale le long de vallees fortement encaissees dans le plateau ardennais. Le processus de patrimonialisation passe par une appropriation conduisant a une forte affirmation identitaire aux facettes diverses, identite paysagere, reconstruction d’une memoire collective technique mais aussi sociale, parfois contestee. L’appropriation de ce patrimoine a ete appuyee par un travail d’approfondissement de sa connaissance. Dans quelle mesure sa valorisation peut-elle contribuer au developpement territorial ?

Liming effect on radial growth depends on time since application and on climate in Norway spruce stands

During the 1980s and 1990s, liming was largely used as a tool to protect or restore forest stands located on acid soils from further acidification due to atmospheric deposition. Whereas impacts on soil properties and tree nutrition are well documented, little is known about the long-term temporal impact of liming on radial growth, and on the effect of climate on this response.We therefore analysed time series of radial increment on 128 dominant trees from spruce liming trials located in the Belgian (Gouvy, 1995–2008) and French (La Croix-Scaille, 1981–2008) Ardennes; these stands were limed at ca 40–45years old. The growth gain associated with liming (GGL, %) was defined by the ratio of the difference in Mean Individual Basal Area Increment between treatments (BAINC limed–BAINC control) corrected for initial differences, to BAINC of the control trees. The effect of climate on GGL was assessed by computing the difference between precipitation (P) and evapotranspiration (PET) over three reference periods of the current growing year (March–June, July–September, March–September).Liming resulted in a two stage growth response pattern. In the first stage (4–8years after treatment), GGL increased up to a maximum value of 29% in Gouvy and 54% in La Croix-Scaille. In a second stage, GGL decreased linearly with time from application while remaining >0. In La Croix-Scaille, the residuals around this tendency (Y) were positively and linearly related to the difference (P–PET; X) during the current vegetation period (Y=0.0037X−0.68; R2=0.36, P=0.0029), suggesting tree response to liming depended on water availability. Compared to the control, liming increased the expected growth response that is described by the linear trend, without considering the variation due to climate.

River management and habitat characteristics of three sympatric aquatic rodents: common muskrat, coypu and European beaver

The ecological environment of three aquatic rodents was studied in the French Ardennes region. Two species, the coypu (Myocastor coypus) and the common muskrat (Ondatra zibethicus), are invasive. By contrast the native European beaver (Castor fiber) was extirpated from the region, subsequently reintroduced, and currently is protected. The aim of this study was to compare the ecological requirements of these three species and predict their future range distributions. We studied the relationship between the species and describe the characteristics of waterways and riparian vegetation in 29 sampling sites. Coypus and muskrats were observed in a variety of riparian habitats and their probability of detection appeared to be independent of waterway width, bank height or bank slope. The availability of numerous herbaceous plants, known to be consumed by these species, may facilitate their settlement. Muskrats are widespread on the French Ardennes waterways, but coypus have not yet colonised the northern part of the region. On the other hand, the beaver was observed primarily in the widest waterways with high banks, where woody plant species, such as Betula, Carpinus and Fraxinus, are found in abundance. Potentially favourable sites for beaver and coypu settlement were analysed to suggest appropriate management according to each species’ status. However, the number of sample sites is weak, especially for sites with beaver, limiting our conclusion.

Exceptionally well‐preserved brittle stars from the Pliensbachian (Early Jurassic) of the French Ardennes

Abstract: Two new genera and species of ophiuroid, Inexpectacantha acrobatica new gen. et sp. and Eirenura papillata new gen et sp., are described on the basis of 39 articulated specimens and several hundreds of arm fragments and isolated skeletal parts. The material was extracted from a lumachellic bed in a late early Pliensbachian succession of argillites at Sedan, French Ardennes. The material is unusually well preserved with even finest structures of the skeleton discernible. Despite the exceptionally detailed morphological data extractable from the material, the higher taxonomic classification in the system of recent ophiuroids could only be tentatively attained. Inexpectacantha acrobatica seems best placed within the Ophioplinthacinae inside the Ophiacanthidae whereas Eirenura papillata shares greatest similarities with the Ophioleucinae. The occurrence of articulated specimens of different sizes, with some of the most delicate skeletal structures left intact, together with completely disarticulated skeletons of the same species suggests that the ophiuroids were preserved as autochthonous faunule among an in situ population of Modiolus sp. during a period of more favourable bottom water conditions in an otherwise largely hostile near‐shore soft‐bottom environment. Based on its small size, the highly flexible arms and the presence of well‐developed hooks on distal arm segments, an epizoic way of life is inferred for I. acrobatica while E. papillata, with its rigid arm structure and the conspicuously large tentacle pores, is interpreted as mostly deposit‐feeding bottom surface dweller.

A new echinoderm Lagerstätte from the Pliensbachian (Early Jurassic) of the French Ardennes

A succession of clays with thin shell beds from the French Ardennes, dated to the late Early Pliensbachian Davoei Zone and yielding abundant well-preserved remains of all five extant classes of echinoderms, is described here as a new Lagerstatte. The echinoderms occur in the form of isolated ossicles, semi-articulated plate aggregates and abundant intact skeletons with even the most delicate appendices preserved in place and the finest skeletal structures hardly blurred by recrystallisation. The outstandingly good preservation of the echinoderm specimens allows for a morphological assessment of the represented taxa in detail only rarely achievable by fossil material. The material described herein thus significantly contributes to a better understanding of the systematic position and phylogenetic background of many Early Jurassic echinoderm taxa. The echinoderms are considered to have been buried as an autochthonous or at least parautochthonous assemblage among clumps and beds of Modiolus bivalves. The depositional setting most likely represented a relatively shallow, near-shore soft-bottom environment in which conditions repeatedly favoured the settlement and subsequent effective burial of bivalve-echinoderm assemblages, leading to the formation of the thin highly fossiliferous shell beds intercalating the otherwise nearly sterile clays. The new Lagerstatte opens a unique window into the palaeoecology of an extinct shallow-water soft-bottom community closely comparable to recent analogues.

New Insight on the “Cul d’Houille” Section (Givetian, Middle Devonian) Near Flohimont (Ardennes, France)

The Cul d’Houille section outcrop, located on the southern border of the Dinant synclinorium (French Ardennes), partly exposes a carbonate series from the middle to upper Givetian (Middle Devonian). This study presents 1- the complementary description of some new recently washed beds, belonging to the lower member (Flohimont Mb.) of the Fromelennes Formation, and 2- the precise location of the member and formation boundaries allowing correlation with the Givetian type sections in southern Ardenne.

New Insight on the “Cul d’Houille” Section (Givetian, Middle Devonian) Near Flohimont (Ardennes, France)

The Cul d’Houille section outcrop, located on the southern border of the Dinant synclinorium (French Ardennes), partly exposes a carbonate series from the middle to upper Givetian (Middle Devonian). This study presents 1- the complementary description of some new recently washed beds, belonging to the lower member (Flohimont Mb.) of the Fromelennes Formation, and 2- the precise location of the member and formation boundaries allowing correlation with the Givetian type sections in southern Ardenne.

Ecological and biological factors involved in the transmission ofEchinococcus multilocularisin the French Ardennes

In order to identify the respective importance of the ecological and biological factors involved in the transmission of Echinococcus multilocularis, we estimated grassland vole intermediate host (Microtus sp. and Arvicola terrestris) population densities, in relation to the diet of the definitive host (red fox, Vulpes vulpes) and with the prevalence of E. multilocularis in the fox population. The study was conducted in the Ardennes, north-eastern France, which is an area with a high incidence of alveolar echinococcosis. Surface index methods showed that Microtus was the most abundant intermediate host in the area. Furthermore, Microtus was present in one-third of the 144 faeces and 98 stomach content samples examined and represented more than two-thirds of the rodent occurrences. Red fox predation on Microtus was significantly correlated with Microtus relative abundance. In contrast, the relative abundance of A. terrestris was very low. This species, as well as Clethrionomys glareolus and Apodemus sp., was little consumed. E. multilocularis prevalence in foxes was determined from carcasses and reached 53% (95% confidence interval 45-61%). Intensity of infection varied from 2 to 73,380 worms per fox, with 72% of the sampled worm burden harboured by 8% of the sampled foxes. The selected explanatory variables (sex, year, age class, health and nutritional condition, and season) failed to predict prevalence rate and worm burden. The high prevalence rate in foxes indicates the possibility of intense E. multilocularis transmission, apart from periods, or in landscapes, favourable to large population outbreaks of grassland rodents.

Genetic diversity of Echinococcus multilocularis on a local scale

Echinococcus multilocularis is the causative agent of human Alveolar Echinococcosis (AE), and it is one of the most lethal zoonotic infections in the Northern Hemisphere. In France, the eastern and central regions are endemic areas; Franche-Comté, Lorraine and Auvergne are particularly contaminated. Recently, several human cases were recorded in the French Ardennes area, a region adjacent to the western border of the E. multilocularis range in France. A previous study in this focus described a prevalence of over 50% of the parasite in red foxes. The present study investigated the genetic diversity of adult worms collected from foxes in a 900 km 2 area in the Ardennes. Instead of a conventional mitochondrial target (ATP6), two microsatellite targets (EmsB and NAK1) were used. A total of 140 adult worms isolated from 25 red foxes were genotyped. After hierarchical clustering analyses, the EmsB target enabled us to distinguish two main assemblages, each divided into sub-groups, yielding the differentiation of six clusters or assemblage profiles. Thirteen foxes (52% of the foxes) each harbored worms from at least two different assemblage profiles, suggesting they had become infected by several sources. Using the NAK1 target, we identified 3 alleles, two found in association with the two EmsB assemblages. With the NAK1 target, we investigated the parasite breeding system and the possible causes of genetic diversification. Only one fox harbored hybrid worms, indicative of a possible (and rare) occurrence of recombination, although multiple infections have been observed in foxes. These results confirm the usefulness of microsatellite targets for assessing genetic polymorphism in a geographically restricted local range.

Risk factors for human hantavirus infection: Franco-Belgian collaborative case-control study during 1995-6 epidemic

Puumala hantavirus is the most common human hantavirus infection in Europe. 1 2 It is transmitted to humans by inhalation or contamination of skin breaches by urine or faeces of...

Acidification des eaux de surface et charges critiques d'acidité: le cas du massif des ardennes françaises

A survey on the sensitivity of freshwater to acidification was performed in the French Ardennes Massif. For that purpose, the relationships between acidifying factors (such as atmospheric deposition), buffering factors (such as bedrock and soil type) and surface water acidity were investigated. Critical loads of acidity were calculated for 36 characteristic streams. Results show that spruces, aluminium-enriched schists and plateaus with silts seem to be the most important factors controlling surface water chemistry. Such a combination occurs in the central part of the French Ardennes, where 70 % of the investigated streams were found to be acidic. Moreover, the corresponding critical loads for these catchments are the lowest in this area (< 1.2 keq·ha −1·yr −1).

The effects of liming and gypsum applications on a sessile oak ( Quercus petraea (M.) Liebl.) stand at La Croix-Scaille (French Ardennes) I. Site characteristics, soil chemistry and aerial biomass

In a former 45 to 50 year old sessile oak ( Quercus petraea (M.) Liebl.) coppice mixed with birch (Betula pubescens Ehrh.) and rowan (Sorbus aucuparia L.) on a poor acidic forest soil at la Croix-Scaille in the French Ardennes, several liming amendments were applied in 1990 and 1994. Data on soil and soil solution composition, as well as stand growth and foliar composition were collected between 1994 and 1997. All treatments, containing 1.4 t ha-1 equivalent of CaO supplied as lime, gypsum or a mixture of the two, resulted in an increase of cation exchange capacity and base saturation down to 15 cm and for CaSO4 treatments down to 30 to 45 cm, increases of soil pH and Ca concentration at the surface and a decrease of Al concentration in the soil and soil solution in the surface layers. No negative effects like increased nitrate or cation leaching were observed. Although Mg nutrition was not improved by the treatments (not containing Mg), a relative and maintained gain of radial increment of sessile oak in the order of 40% for both lime and gypsum applied, was observed immediately from the first year on, after the application (1991).

The effect of lime and gypsum applications on a sessile oak (Quercus petraea (M.) Liebl.) stand at La Croix-Scaille (French Ardennes) II. Fine root dynamics.

Fine root distribution, quantities, dynamics and composition were studied in a sessile oak coppice stand in the French Ardennes on an acidic soil (< pH-H2O 4.5), one to five years after lime or gypsum applications. Fine root biomass and length increased and specific root length decreased after lime or gypsum treatments. The treatment responses were strongest four to five years after the applications, but the tendencies after one year were similar. The effects were pronounced in the top 15 cm but also at 30–45 cm four to five years after liming. The latter effect suggests an indirect positive feedback from the aerial parts of the trees into the deeper soil layers. Sequential sampling for two years revealed large differences in total fine root length between the years, and also indicated that fine root turnover was lower after liming or gypsum applications than in the control. This seemed to be related to a lower fine root mortality and higher longevity rather than to increased fine root production. The improved nutrient status of the fine roots corroborates this and coincides with improved foliar nutrition and tree growth. Moderate doses of lime and gypsum appeared effective in enhancing root system uptake function, resulting in increased above ground growth.

Consequences of liming and gypsum top-dressing on nitrogen and carbon dynamics in acid forest soils with different humus forms

The aim of this study was to understand the effects of lime and gypsum on nitrogen and carbon turnover of the soil. A pot experiment was conducted in parallel with a field experiment which was set up in 1989 in a declining forest of the French Ardennes. A dystric cambisol, associated with a moder and mull humus separately, was used to study changes in the soil chemistry as a result of added lime and gypsum top-dressing.

A nitrogen cycle model for calculating the reduction of N-input necessary to reduce soil acidification and nitrate leaching and the consequences of this for wood production

The biogeochemical cycle of elements has been established in a spruce stand in the French Ardennes on a site with a poor acidic soil and a large inputs of nitrogen and sulphate from the atmosphere. This paper shows the interest of studying the seasonal N cycle instead of the global annual cycle, because part of the N input seems to be immobilized in the soil during the dormant season and is released afterwards and taken up during the growing season, and because of the important participation of N inputs in the N-uptake by trees during the growing season. The very large amount of NO3-N leached towards the water table level should be reduced. Using the seasonal cycles, we discuss the relationship between the desirable reduction in the NO3-N output and the N (NH4-N + NO3-N) input. A fertilization trial, including N and Ca, shows a decrease in the wood production after N fertilization. These models give us the opportunity to calculate the reduction of wood production in relation to the reduction of the N input in the ecosystem.

Fertilization of declining conifer stands in the Vosges and in the French Ardennes

Fertilization of declining conifer stands in the Vosges and in the French Ardennes

Fertilization of declining conifer stands in the vosges and in the French Ardennes

Twenty fertilization experiments were set up in 1985 and 1986 in the Vosges mountains, using mostly calcareous or Mg fertilizers, in order to verify whether fertilization can attenuate defoliation and yellowing recently recorded in Silver fir and Norway spruce. In the Ardennes, a fertilization experiment set up in Norway spruce stands prior to the appearance of yellowing was assessed. In these areas, the total acid deposition is about 2 kg eq H+ ha−1 yr−1. Nitrogen deposition is much more important in the Ardennes (52 kg N ha−1 yr−1 in form of wet and dry deposition) than in the Vosges (16 kg N ha−1 yr−1). The results in the eight adult stands showed no uniform reaction to the treatments. Spontaneous improvement, further deterioration independently of the treatment, as well as a positive reaction to fertilization were observed. Additional N or P fertilization sometimes had a beneficial effect on Ca or Mg treatments. The selection of the stands with the best response turns out to be difficult, as the nutrient contents of needles alone seem not to be a satisfactory criterion for selection. Young plantations reacted positivley to the treatments. Soluble Mg fertilizer leads to an immediate response. Low solubility Ca-Mg fertilizers (Ca-Mg lime) did not produce reactions until three years after the application. In the Ardennes, in a 40 yr old spruce stand suffering from severe Mg deficiency, a Ca and Ca-phosphate fertilization applied 5 yr before yellowing appeared had positive effects on crown density, discoloration and wood production. Conversely, a single N fertilization in this experiment, as well as in a young plantation in the Vosges, had a marked negative effect on Mg nutrition, even at low levels.