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1.
New grylloblattid insects (Grylloblattida) are described from the Grès à Voltzia of the Vosges (Anisian of Alsace and Lorraine, France): Chauliodites anisicus, sp. nov. (Chaulioditidae), Palaeomesorthopteron pullus gen. et sp. nov. (Mesorthopteridae), Megakhosarodes vosgesicus sp. nov. (Megakhosaridae), Dorniella elcanoides sp. nov., D. apectinata sp. nov., D. diluta sp. nov., D. ovalis sp. nov., Baharellinus umbrosus sp. nov. Embigryllus shcherbakovi gen. et sp. nov., and Vosgesopterum arzvillerensis gen. et sp. nov. (Blattogryllidae).  相似文献   

2.
E. Chauvet  A. Fabre 《Hydrobiologia》1990,192(2-3):183-190
Water contents of suspended matter, algal pigments, particulate organic carbon and particulate phosphorus were measured in the rivers Garonne (2 sites) and Ariège (1 site) throughout an annual cycle. The general trend of the parameters was similar at the three sites. Depending on the sites, the period of algal growth (chlorophyll a + phaeopigments > 25 µg l–1), lasted from two to six weeks in August–September. The algal peaks reached 50 to 90 µg 1–1 of total pigments. High contents of particulate organic carbon (> 2 mg 1–1) occurred at the end of summer (coinciding with algal growth), and during the November and May floods. In summer 50–75 % of the suspended matter was organic, in spring this was 10 times less. The high linear correlation between particulate organic carbon and pigment contents (r = 0.87; P = 0.0001) suggested an algal origin of at least part of the particulate carbon. Algal carbon was minor in the annual fluxes of particulate carbon (25 to 39% depending on the sites), but relatively high in comparison with other rivers. The mean particulate phosphorus content calculated over the year was 24 µg l–1 ; it varied from 15 µg l–1 during the high water period to 28 µg 1–1 during the low water period. Likewise the percentage of particulate phosphorus in the suspended matter varied from 0.17 to 0.40. A negative linear correlation existed between particulate phosphorus content and specific discharge (r = – 0.46; P = 0.0001).The very marked seasonal trend of the parameters and the interactions led us to differentiate two modes of the rivers' functioning: a hydrologic phase and a biological phase. The hydrologic phase (high water) was dominated by the processes of erosion and transfer over the whole catchment area and the flood plain, while the biological phase was characterized by a high primary production in the river bed.  相似文献   

3.
Seasonal sampling at six locations on the Lower Ardèche River was effected irregularly during 1982, 1983 and 1984. The seasonal structure of the taxa-sample matrix, much more important than sample location, is demonstrated using graphical interpretation.The Mediterranean aspect of the lower reaches of the Ardèche River is pointed out through its community structure which includes species often collected in other typical Mediterranean streams, e.g. Oligoneuriella rhenana, Ephoron virgo, Ecdyonurus dispar, E. insignis, Choroterpes picteti.Water temperature and day length were the determinant influences on seasonal variations in population structure of benthic macroinvertebrates. Three periods were distinguished: water (November to April), spring (May, June and beginning July) and summer (end of July to October). Spring and autumnal spates marked the limits of the summer and winter periods. Hence, annual fluctuations of this seasonal typology may occur in response to the hydrological regime.  相似文献   

4.
From a quantitative inventory of sulphur forms and sulphur budget, the relation between the distribution of the various sulphur forms and the sulphate fluxes in three soil profiles has been addressed. These profiles are located in two forested watersheds at Mont Lozère. One has been sampled in a beech forest and the other two in a spruce forest and in a harvested plot of this spruce forest, respectively. The mean annual input-output budgets showed a sulphur immobilization in the soil cover of the three plots. In the preserved spruce forest plot, because of larger dry depositions, the sulphur immobilization is much greater than in other plots and occurs essentially in the B horizons. In the other two profiles, the dominant immobilization occurs in the parent material.The total sulphur content is very high in the forest floor reaching 2065 g S g-1 in the litter of one of the soils under spruce. In the organo-mineral horizons of soils under spruce, the total sulphur content decreases with depth and ranges from 310 to 520 g S g-1 in the A horizons to 100–200 g S g-1 in the parent material. In the profile under beech, the total sulphur content is lower except in the parent material. In all cases, the organic sulphur is the major part of sulphur often representing more than 90% of total sulphur. In organo-mineral soil horizons of the spruce forest, the part of the sulphateesters is more important than in the soil of the beech forest, probably related to the different nature of the microbial activity in the spruce forest. In contrast, the humification processes are more efficient in the soil under beech, which can be due to the greater input of organic sulphur by litterfall. It appears that the dominant organic sulphur form varies as a function of microbial ecology and sulphate flux. The maximum of the inorganic sulphate is located at the base of the B horizons in the soil of the spruce forest and in the parent material of the soil under beech. In these horizons, the high content of inorganic sulphate can be related to the higher amounts of amorphous Fe and Al phases.  相似文献   

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6.
During the 20th century, the first dinosaur tracks of the Causses Basin were identified at Saint-Laurent-de-Trèves, in the Parc National des Cévennes (southern France). A recent excavation reveals a new theropod tracksite in the Hettangian deposits from Le Mazel, 2 km from the historical tracksite at Saint-Laurent-de-Trèves. The tracks are here described combining a biometric approach and 3D imaging photogrammetry. The main track-bearing surface bears 64 in situ tridactyl footprints preserved as concave epireliefs. Two morphotypes were identified, a “Grallatorid” morphotype and a “Kayentapus” morphotype. Footprints belonging to the first morphotype are closely similar to Grallator lescurei, Grallator minusculus, and Grallator sauclierensis. This study shows the difficulty to distinguish quite similar tridactyl tracks from an ichnotaxonomic point of view and highlights the importance of detailed biometric comparisons. Tracks are preserved in a brown to yellowish dolomudstone showing abundant cryptalgal laminites and mud cracks. These deposits were accrued in shallow environments such as intertidal and supratidal zones of a tidal flat.  相似文献   

7.
Summary

New insects are described from the Middle Permian (Guadalupian) of Salagou Formation in the Lodève Basin (Languedoc region, France). Palaeopterans are represented by new odonatopterans viz. Huangiopterum lodevense n. gen., n. sp. and Huangiopterum species B, attributed to clade Panodonata (Huangiopteridae n. fam.), already recorded through the family Saxonagrionidae in the same formation, and a diaphanopterodean Martynovia cf. halli Beckemeyer 2004 (Martynoviidae) known from the Lower Permian of Oklahoma. Archaeorthopterans are supplemented by Bethouxia ariegensis n. gen., n. sp., Paralongzhua elongata n. gen., n. sp., Lodevolongzhua incompleta n. gen., n. sp., the caloneurodean Jarmiloptera mouralensis n. gen., n. sp., and a cnemidolestodean cf. Tococladus sp. (Tococladidae). Permophyllum rotundatum n. sp. (?Tettigoniidae) demonstrates the first presence of Orthoptera with wings probably mimicking Peltaspermales reproductive organs in Late Palaeozoic possibly analogous to the known crypsis of roachoid tegmina with pteridosperm pinnules. Frequent occurrence of hardly identifiable grylloblattid wing fragments support their significant role in term of abundance and diversity of the Permian faunas. New taxa based on wing venation pattern as Genera and species undetermined A, B (Liomopteridae), Permobaharellus salagousensis n. gen., n. sp. (family uncertain), Lodevophlebia reticulata n. gen., n. sp. (Sylvaphlebiidae), Oborella lodevensis n. sp. (Euryptilonidae), and Genus and species undetermined C, were described. Paoliida is represented by a paoliid gen. et sp. indet. and three anthracoptilids Strephocladus gandi n. sp., Strephocladus mouralensis n. sp., Lodevocladus subtilis n. gen., n. sp. The first record of miomopteran Palaeomantis sp. (Paleomanteidae) from Salagou Formation is presented. Acercarian insects are represented by the first record of Thripida and diverse new hemipterans, namely Euroscytina lutevanorum n. gen., n. sp. (Cicadomorpha: Scytinopteridae), Prosbole dio n. sp., Prosbole garrici n. sp., Pervestigia cf. veteris Becker-Migdisova 1961 (Prosbolidae), Archescytina species A (Paleorrhyncha: Archescytinidae) and Permopsyllidium lesclansis n. sp. (Sternorrhyncha: Psylloidea: Protopsyllidiidae). Entomofauna from the Salagou Formation demonstrate highly diverse insect communities with some taxa linked to early and late Permian ones known from assemblages in Euramerica and Russia, such as Obora (Czech Republic), Wellington Formation (Kansas and Oklahoma, USA), and Tshekarda (Ural, Russia).  相似文献   

8.
Michel Melou 《Geobios》1976,9(6):693-717
Three species of Orthida are described from the «Schistes de Postolonnec Formation. The distribution of Crozonorthis musculosa n. g., n. sp. allows to improve the correlations between the Iberic Peninsula and the Armorican massif and supply new arguments for a Llandeilian age to a part of the «Schistes de Postolonnec Formation.  相似文献   

9.
Based on the individual growth, food limitation,population renewal through seeding, and individualmarketable size, a theoretical model of the culturedspecies population dynamics was used to assess thecarrying capacity of an ecosystem. It gave adome-shape curve relating the annual production andthe standing stock under the assumption of individual growth limited by the available food inan ecosystem. It also showed the influence ofmortality rate and marketable size on this curve andwas introduced as a means to explore the globalproperties resulting from the interactions betweenthe ecophysiology of the reared species and theenvironment at the ecosystem level. In a second step, an ecosystem model was built to assess the carryingcapacity of Marennes-Oléron bay, the mostimportant shellfish culture site in France, with astanding stock of Crassostrea gigas around 100000tonnes fresh weight (FW) and an annual production of30000 tonnes FW. The ecosystem model focused on theoyster growth rate and considered the interactionbetween food availability, residence time of thewater, oyster ecophysiology and number ofindividuals. It included a spatial discretization ofthe bay (box design) based on a hydrodynamic model,and the nitrogen or carbon cycling betweenphytoplankton, cultured oysters, and detritus. Fromsimulations of the oyster growth with differentseeding values, a curve relating the total annualproduction and the standing stock was obtained. Thiscurve exhibited a dome shape with a maximumproduction corresponding to an optimum standingstock. The model predicted a maximum annualproduction of 45000 tonnes FW for a standing stockaround 115000 tonnes FW. The prediction confirmedsome results obtained empirically in the case ofMarennes-Oléron bay and the results of thetheoretical model. Results were compared with thoseobtained in Carlingford Lough (Ireland) using asimilar ecosystem model. Carlingford Lough is asmall intertidal bay where the same species iscultured at a reduced scale, with current biomassless than 500 tonnes FW. The model showed that thestanding stock can be increased from 200 tonnes FWto approximately 1500 tonnes FW before any decreaseof the production. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

10.
《Comptes Rendus Palevol》2018,17(7):479-493
Diatomite deposits of Saint-Bauzile near Privas (Ardèche) in southern France have been known since more than two centuries for abundant and extremely well-preserved fossils of plants and animals. The radiometric dating brackets fossil-bearing horizons between 7.2 and 7.6 Ma, which is consistent with the biochronologic age given by fossil mammals, which are characteristics of the late MN11 zone, i.e. the second part of the late Miocene. The main interest of this site for mammals is that they are preserved almost “in the flesh”, as entire skeletons with bones in their anatomical connection, and often with skin and fur charred and forming a halo around the body. In this work, we studied the remains of a lagomorph, two rodents, an equid, a suid, a bovid and a rhino. The mode of preservation of mammals as entire bodies suggests sudden death and rapid burial of individuals.  相似文献   

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AIMS: To isolate, identify, and characterize heterotrophic bacteria in acid-mine drainage that mediate oxidation of As(III). METHODS AND RESULTS: Samples of acid-mine drainage were collected over a period of 14 months. Heterotrophic and non-obligatory acidophilic bacteria in the samples were cultured on a solid medium (pH 7.0-7.2), and three strains were isolated. The three different strains belong to the genus Thiomonas, and have more than 99% homology with the group Ynys1. Culturing in mineral media demonstrated that the isolated strains used thiosulphate as an energy source, and oxidized iron in the presence of thiosulphate. However, none of the strains were able to oxidize arsenic in the presence of thiosulphate, nor could they use iron or arsenic alone as an energy source. In vitro experiments demonstrated that two of the Thiomonas strains were able to oxidize more than 90% of the As(III) present in the acid-mine drainage, whereas no abiotic oxidation of arsenic occurred. CONCLUSIONS: Two strains of newly identified Thiomonas sp. found in acid-mine drainage are capable of oxidizing arsenic. SIGNIFICANCE AND IMPACT OF STUDY: These results represent the first reported oxidation of arsenic by Thiomonas sp. Biologically mediated oxidation and subsequent immobilization of arsenic is of great interest for the remediation of contaminated mine sites.  相似文献   

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14.
The Upper Cenomanian cover of the Palaeozoic Mouthoumet Massif (southern Corbières, Aude, France), on the southern flank of the Bézu anticline, shows accumulations of large platy corals. However, while being already presented in stratigraphic, palaeoecological and sedimentological contexts, these organisms have not been the subject of a palaeontological study. The coral fauna encompasses 16 species of the families Leptophylliidae, Microsolenidae, and Siderastraeidae and is here presented in detail.  相似文献   

15.

The microbial communities have been investigated in the subsurface waters of the Carnoulès pyrite-rich tailings impoundment (France) for two hydrological situations characterized by the presence of oxygenated waters during winter and suboxic conditions in early autumn. In these acidic waters (2–5) characterized by elevated concentrations of Fe (1608–3354 mg · l?1), As (130–434 mg · l?1) and sulfates (5796–14318 mg · l?1) and variable dissolved oxygen content, the cultivable bacteria found in these system are Thiomonas and Acidithiobacillus ferrooxidans. Molecular methods, Terminal-Restriction Fragment Length Polymorphism (T-RFLP), and 16S rRNA encoding gene library analysis indicate low diversity. The environment is dominated by only a few types of microorganisms, with 70–80% of the whole bacterial population assigned to two or three Terminal-Restriction Fragments (T-RFs). Most of these organisms are uncultured, newly described, or recently associated with acid mine drainage. Modifications of the community structure are observed as a function of the sampling period and seem to be related to the aqueous chemistry of the tailings water. At low Dissolved Oxygen (DO = 1 mg · l?1) concentrations and moderately acidic conditions (pH = 5.7), the dominant organisms are related to the uncultured clone BA31 affiliated with Desulfosarcina variabilis, a sulfate-reducing bacteria (SRB), Acidithiobacillus ferrooxidans and the uncultured clone BVB20, closely related to Thiobacillus. At high (12 mg · l?1) DO concentrations and low (< 2) pH values, the microbial diversity is less important and 65% of the population is assigned to the uncultured bacterium clone AS6 related to Desulfosarcina variabilis.  相似文献   

16.
The site of Les Auzières 2 (Méthamis, Vaucluse) was excavated from 2001 to 2005. It yielded an original and diverse fauna, unique in southeastern France (Provence). The spectrum of large mammals comprises 14 species including hyena, horse, ibex, woolly rhinoceros, giant deer and mammoth. Lithic artifacts are rare but testify to the presence of a Mousterian industry. All of these remains derive from layers that have been dated to 60 ± 10 ka by ESR/U-series method. Les Auzières 2 is of special importance for examining the issue of human/carnivore interaction in the Pleistocene since it has yielded a large assemblage of carnivore remains, and probably represents a hyena den. The diverse fauna offers a more comprehensive picture of Upper Pleistocene biodiversity in southeastern France than that usually provided by sites with a stronger anthropogenic signal.  相似文献   

17.
Summary The authors studied the phenotypic distribution of -L-fucosidase in a random sample of the population of the area of Rennes (France). The frequencies of Fu 1 (0.64) and Fu 2 (0.36) genes are significantly different from the frequencies observed in New York whites and blacks.  相似文献   

18.
Limnology - Controlling phosphorus is fundamental to limit the risk of eutrophication of continental aquatic ecosystems. Integrated modelling of its concentration in the aquatic continuum requires...  相似文献   

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