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1.
We examined taxonomic and geographic patterns of the obligate groundwater fauna (i.e. stygobiotic fauna) by assembling in a distributional data base all species occurrences reported from France since 1805. A simulated annealing algorithm was used to identify conservation targets. Until the 60s, biological surveys were restricted to caves but the proportion of sampling sites in unconsolidated sediments increased from 1 to 16% over the last 40 years. A total of 380 species and subspecies in 40 families were collected, 70% of which being restricted to France. As observed in other temperate regions, the stygobiotic fauna was dominated by crustaceans (65% of species) and molluscs (22%). The cumulative number of species did not level off over time, clearly showing that biodiversity was underestimated. Temporal trends in the cumulative number of obligate groundwater and surface water species suggested that groundwater comprised more crustaceans than surface freshwater. Endemism was high although the geographic range size of species increased as distributional data accumulated. Of 380 species, 156 were known from a single 400-km2 cell, among which 73% were located in the southern third of France. The distribution map of species richness changed dramatically over time, indicating that the location of richness hotspots was sensitive to sampling effort. Less than 2% of the French landscape was needed to capture 60% of known species. Thus, a large proportion of species could be protected by focusing habitat conservation efforts on a few complementary species-rich aquifers located in distinct regions.  相似文献   

2.
Shallow-marine limestones associated to a Palaeotethyan seamount in the Teke Dere unit of the Tavas Nappe (Lycian Nappes, SW Turkey) are essentially latest Moscovian-Kasimovian in age. The wide range of microfauna and -flora of the series show biogeographic affinities comparable to those from the northern Palaeotethyan borders (especially to assemblages from the Carnic Alps, Urals, Donbass and Darvaz). These biogeographic affinities seem to persist until the end of the Early Permian (Artinskian). The Middle Permian fauna is represented by the typical warm, tropical assemblages known at the same time in the Palaeotethys (NW Caucasus, Darvaz, south China, Primorie and Japan), and in the Neotethys (Transcaucasia, central Iran, southern Afghanistan and Sibumasu). The new Kasimovian algae and incertae sedis Novantiellopsis elliottii n. gen. n. sp., Uvanellopsis fluegelii n. gen. n. sp., Tubiphytes rauzerae n. sp. and Asselodiscus davydovi n. sp. are described.  相似文献   

3.
4.
Late Pennsylvanian succession of the Picos de Europa Unit (Cantabrian Mountains, NW Spain) constitutes one of the few exposed marine strata of this age in Western Europe. It consists of synorogenic deposits that accumulated in piggy-back basins developed during the latest stages of the Variscan orogeny. The 11 mappable 3rd, 4th–5th order depositional sequences that form the succession were subdivided in higher-order cycles (5th order) and grouped into two sequence sets. Fusulinoidean faunas have allowed dating of these strata (late Myachkovian-Gzhelian) and to characterize each depositional sequence. Sequence stratigraphy, coupled with sedimentological and paleontological analysis have enabled the reconstruction of a sea level curve that may shed light on Late Pennsylvanian global events and faunal migrations. These studies suggest potential correlations between late Moscovian cycles recognized both in the Cantabrian Mountains and in the Moscow Basin. Sudden appearances of early Dorogomilovian and early Gzhelian fusulinoideans could indicate migrations within the Paleotethys, probably favoured by global sea level rises and highstands.  相似文献   

5.
The vegetation of shallow depressions on Ivorian granite inselbergs was studied along a gradient from the savanna zone in the north to the rainforest zone in the south of the country. Short-term inundation and prolonged drought are typical features of this habitat. In total, 64 taxa belonging to 25 families were recorded, with the Poaceae, Cyperaceae and Fabaceae accounting for the greatest proportion of species. Annuals represent the predominant life form and comprise nearly two thirds of all species recorded. DCA ordination of the sample plots illustrates that diversity decreases from north to south, and is accompanied by a gradual transition in the ambient vegetation from savanna to rainforest. This decrease is in marked contrast with diversity of surrounding vegetation types. In the drier northern area, it appears as if the less favourable environmental conditions prevent a state of community equilibrium being attained in the shallow depressions. This enables weak competitors to co-exist along with more vigorous species, which, in the south of the country, form species-poor stands. Furthermore, the fact that inselbergs in the rainforest zone are more isolated enhances the probability of extinction of less competitive associates.  相似文献   

6.
Starting from previous work on tropical african fishes (de Merona et al., 1983), we calculate a relationship between Loo and k and between LOO and the maximum observed length in cyprinid populations of some French great rivers and associated man-made lakes (basins of Garonne and Rhone). 45 populations are used, and they seem to conform to the model well. The growth of both groups of populations differs only by the value of some constants. This follows from differences in the individual growth pattern of fishes, climate, and from differences in food and feeding habits.  相似文献   

7.
The lower and lowermost Middle Ordovician strata of the Volkhov Stage exposed in the vicinity of St. Petersburg, Russia, yield a graptolite fauna at several stratigraphic levels, being more often confined to the mud-mound clays than to the normally stratified, Condensed carbonates. Overall taxonomic diversity of the Volkhov graptolites is relatively low and associations include no more than seven species in ail localities. TheTetragraptus, Didymograptus andXiphograptus species found are pandemic and have quite extensive stratigraphie ranges within the mid-Arenig Series. Based on the graptolite zonation, the Volkhov Stage can be correlated to thePseudophyllograptus angustifolius elongatus andDidymograptus (Expansograptus) hirundo graptolite biozones of Baltoscandia and to the upperDidymograptus simulans toDidymograptus (Expansograptus) hirundo biozones of the British graptolite succession. TheIsograptus victoriae lunatus lower zonal boundary probably falls within the graptolite-bearing interval of the lower Volkhov Stage. As the result of indirect biostratigraphic and interpretative lithological correlations, the first appearance ofUndulograptus austrodentatus at the base of the Darriwilian Stage is deemed to be close to the boundary of theMegistaspis simon andM. limbata trilobite biozones and the lowerBaltionodus norrlandicus conodont Biozone of the upper Volkhov Stage. Seven dichograptid species belonging to four genera are described, one of them,Azygograptus volkhovensis n. sp., new.   相似文献   

8.
The microbial-dominated part of a Late Mississippian (Early Carboniferous) carbonate olistolite at La Serre (Montagne Noire, southern France) yielded interesting algae and pseudo-algae. The constituents are well known cyanobacteria (not described) and different representatives of poorly known or new species: cyanobacteria: Aphralysia capriorae, Hedstroemia (?) serrana n. sp., Dasycladales: Paraepimastopora sp., Nanopora sp., Cabrieropora pokornyi and E. occitanica, Anatoliporaceae: Richella incrustata, Caulerpales: Poncetellina (?) sp., questionable Archaeolithophyllaceae: Hortonella sp., Archaeolithophyllaceae: Neoprincipia with Neopricipia fluegeli, Neoprincipia petschoriaeformis n. sp., Neoprincipia claviformis n. sp. and Archaeolithophyllum ex gr. lamellosum; pseudo-algae Aoujgaliida: Stacheoidella spissa, Ungdarella uralica, and Fasciellidae: Fasciella and Praedonezella, with both polymorph species: Fasciella kizilia, and Praedonezella ex gr. cespeformis. This carbonate microflora is dated as Early Serpukhovian (Pendleian) by its association with the foraminifera Janichewskina, “Biseriella” and “Warnantella”. This dating is confirmed by the little more advanced algal assemblage, compared to the Latest Visean (Brigantian) assemblages from Montagne Noire (e.g. Japhet, Castelsec), and more primitive than the Late Serpukhovian (Arnsbergian) of Ardengost (Pyrenees). The importance of the calcifoliid pseudo-algae—Fasciella, Praedonezella, and Calcifolium (although this latter is locally lacking)—is suggested for the biozonation of the Visean/Serpukhovian boundary.  相似文献   

9.
Comparing available paleontological, archaeological, historical, and former distributional data with current natural history and distributions demonstrated a turnover in the French vertebrate fauna during the Holocene (subdivided into seven sub-periods). To this end, a network of 53 specialists gleaned information from more than 1300 documents, the majority never cited before in the academic literature. The designation of 699 species as native, vanished, or non-indigenous in France or in one or more of its biogeographical entities during the Holocene period was investigated. Among these 699 species, 585 were found to belong to one or more of these categories. Among the 154 species that fit the definition of non-indigenous, 86 species were new species for France during the Holocene. Fifty-one that were autochthonous vanished from France during this period. Among these 51 species, 10 (two birds and eight mammals) are now globally extinct. During the last 11 millennia, the turnover in the French vertebrate fauna yielded a net gain of 35 species. On a taxon-by-taxon basis, there was a gain in the sizes of the ichthyofauna (19 : 27%), the avifauna (10 : 3%) and the herpetofauna (7 : 9%) and a loss in the mammalian fauna (−1 : 1%). Values of a per-century invasion index were less than 1 between 9200 BC and 1600 AD but increased dramatically after this date. An exponential model fits the trajectory of this index well, reaching the value of 132 invasions per century for the last sub-period, which encompasses 1945–2002. Currently, the local ecological and economic impacts of populations of 116 species (75% of the 154 that satisfied the criteria for non-indigenous) are undocumented, and the non-indigenous populations of 107 vertebrate species (69%) are unmanaged. The delay in assessing the ecological and economical impact of non-indigenous species, which is related to a lack of interest of French academic scientists in the Science and Action programmes, prevents the public from becoming informed and hinders the debates needed to construct a global strategy. For such a strategy to be effective, it will have to be elaborated at a more global scale than in just France – definitely at least in Europe. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

10.
A quantitative study was performed on planktonic foraminifera and calcareous nannofossils of the astronomically dated Late Miocene Pissouri section (Cyprus). Our results confirm the reliability of well-known planktonic foraminiferal events as Catapsydraxparvulus LO (Last Occurrence), sinistral coiling change of Globorotaliascitula, Globorotaliamiotumida group FRO (First Regular Occurrence), Globorotalianicolae FO (First occurrence) and LO, sinistral coiling change of Neogloboquadrinaacostaensis and also of several important calcareous nannofossil events (Amaurolithusprimus FO, Amaurolithusdelicatus FO, Reticulofenestrarotaria FO and FCO). Integrated planktonic foraminifera and calcareous nannoplankton data contribute to an enhanced time resolution of the Tortonian - early Messinian interval in the Levantine basin, and contribute to detailed correlations throughout the Eastern Mediterranean. In addition, we compare methodologies commonly used in calcareous plankton biostratigraphy, and shortly outline sources of bias that can influence the results of stratigraphic studies.  相似文献   

11.
The process of vegetative propagation used to multiply grapevine varieties produces, in most cases, clones genetically identical to the parental plant. Nevertheless, spontaneous somatic mutations can occur in the regenerative cells that give rise to the clones, leading to consider varieties as populations of clones that conform to a panel of phenotypic traits. Using two sets of nuclear microsatellite markers, the present work aimed at evaluating and comparing the intravarietal genetic diversity within seven wine grape varieties: Cabernet franc, Cabernet Sauvignon, Chenin blanc, Grolleau, Pinot noir, Riesling, Savagnin, comprising a total number of 344 accessions of certified clones and introductions preserved in French repositories. Ten accessions resulted in being either self-progeny, possible offspring of the expected variety or misclassified varieties. Out of the 334 remaining accessions, 83 displayed genotypes different from the varietal reference, i.e., the microsatellite profile shared by the larger number of accessions. They showed a similarity value ranging from 0.923 to 0.992, and thus were considered as polymorphic monozygotic clones. The fraction of polymorphic clones ranged from 2 to 75% depending on the variety and the set of markers, the widest clonal diversity being observed within the Savagnin. Among the 83 polymorphic clones, 29 had unique genotype making them distinguishable; others were classified in 21 groups sharing the same genotype. All microsatellite markers were not equally efficient to show diversity within clone collections and a standard set of five microsatellite markers (VMC3a9, VMC5g7, VVS2, VVMD30, and VVMD 32) relevant to reveal clonal polymorphism is proposed.  相似文献   

12.
This paper summarizes the results of investigations carried out in the Mokrá quarry since 2006 on the biostratigraphy of the Tournaisian-Visean (T-V) boundary interval. It also integrates previous results obtained by J. Kalvoda and collaborators. The main focus is on the boundary itself, but stratigraphically lower and higher levels have been investigated as well to provide a biostratigraphical context spanning the late Tournaisian to early Visean. This stratigraphical level has been the focus of intense international research in the recent years under the auspices of the Subcommission on Carboniferous Stratigraphy (SCCS) in order to find a new criterion and reference section (Global Stratotype Section and Point, GSSP) for the base of the Visean Stage. The appearance of Eoparastaffella simplex from its ancestor E.ovalis” and the Pengchong section (Guangxi, southern China) have recently been proposed by the Task Group on the Tournaisian-Visean Boundary and ratified by the SCCS as the new biostratigraphic criterion and GSSP for the base of the Visean, respectively. The sequence exposed in Mokrá is not suitable as a GSSP, notably because it is an active quarry, but it contains most of the foraminifer and conodont guides allowing a high-resolution biostratigraphy of the boundary interval. In addition, it contains abundant trilobites. For these reasons, it constitutes one of the best sections across the T-V boundary in Europe and can serve as a useful additional reference.  相似文献   

13.
On the statistical significance of functional diversity effects   总被引:6,自引:0,他引:6  
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14.
Seven diversity indices were calculated for each of fifty-eight microcosm communities. All fifty-eight communities were initiated from equal density inoculations of fourteen algal species. Each microcosm developed in one of six controlled experimental environments; the environments differing only in their temporal patterns of disturbance. Five linear discriminating techniques were used to evaluate the diversity index most useful for discriminating between these environments. The Shannon-Wiener index was best according to two of the discriminating methodologies and second best using the other techniques. Evenness was best when the Shannon-Wiener index was second best and vice versa.  相似文献   

15.
The study of collembolan communities from the Vîşcăuți canyon in Moldova revealed 63 species belonging to 41 genera and 12 families, including four species new for the fauna of the Republic of Moldova. A checklist of collembolan species identified in the five calcareous canyons sampled so far in Moldova is included, with data on habitats, life form, occurrence and comments of distribution of most remarkable species. Of the 98 recognized species of these calcareous canyons, only 38 were shared by Vîşcăuți and the other canyons. The richness of calcareous habitats together with the high heterogeneity in faunal composition suggests that further significant increase in the species richness of the region may be expected.  相似文献   

16.
Eight monotypic hyphomycete genera new to science are described from the trichomes of native plants growing in the cerrado of Brazil: Trichomatoclava cerradensis, Echinoconidiophorum cerradense, Globoconidiopsis cerradensis, Globoconidium cerradense, Helminthosporiomyces cerradensis, Microtrichosphaera cerradensis, Phragmoconidium cerradense, and Vesiculohyphomyces cerradensis gens. spp. nov. Two of the new genera were found on hosts belonging in Myrtaceae, and one of each of the following families: Icacinaceae, Malphigiaceae, Fabaceae, Dilleniaceae, Chrysobalanaceae, and Caryocaraceae. These discoveries suggest that the trichomes of neotropical plants are an unexplored source of novel fungal diversity, and merit more attention in biodiversity surveys.  相似文献   

17.
The Kangchenjunga Landscape (KL) in the Eastern Himalayas is a transboundary complex shared by Bhutan, India, and Nepal. It forms a part of the ‘Himalayan Biodiversity Hotspot’ and is one of the biologically richest landscapes in the Eastern Himalayas. In this paper, we use secondary information to review and consolidate the knowledge on the flora of the KL. We reviewed 215 journal articles, analysed the history of publications on the flora of the KL, their publication pattern in terms of temporal and spatial distribution and key research areas. Our review shows that the landscape has a long history of botanical research that dates back to the 1840s and progressed remarkably after the 1980s. Most of the studies have been carried out in India, followed by Nepal and Bhutan. The majority of these have been vegetation surveys, followed by research on ethnobotanical aspects and Non-Timber Forest Products (NTFPs). This paper describes the forest types and characteristic species of the KL and details the species richness, diversity and dominant families of seed plants. A total of 5198 species of seed plants belonging to 1548 genera and 216 families have been recorded from the landscape, including 3860 dicots, 1315 monocots and 23 gymnosperms. Among families, Orchidaceae is the most diversely represented family in terms of species richness. This paper also draws attention to the threatened and endemic flora of the KL, including 44 species that are threatened at national and global level and 182 species that are endemic. Finally, the paper reviews the major challenges facing the KL, the conservation efforts and practices that are currently in place and recommends systematic and comprehensive floral surveys, particularly long-term data collection and monitoring and transboundary collaboration, to address the existing knowledge gaps on floral diversity of the KL.  相似文献   

18.
BACKGROUND AND AIMS: Landrace populations represent an important intra-crop reservoir of biodiversity and source of novel gene alleles for use in breeding programmes. Here the aim was to measure the diversity of a wheat landrace, 'Barbela', from the north of Portugal. METHODS: DNA was extracted from 59 accessions of Barbela collected across its geographical range. Diversity was measured by microsatellite length polymorphisms using 27 primer pairs amplifying 34 polymorphic microsatellite loci. KEY RESULTS: High levels of polymorphism were found, with an average polymorphism information content of 0.52; an average of 4.77 alleles (range 2-11) were present at each locus, and half of these loci showed an additional allele in the reference variety 'Chinese Spring'. CONCLUSIONS: 'Barbela' is maintained from seeds collected by farmers, but it maintains high allelic variation, and no groupings of accessions were detected when analysed by geographical region, farm or climate, indicating that the wheat landrace is a homogeneous entity. The diversity within the farmer-maintained landrace demonstrates the importance of characterization and maintenance of landrace collections before valuable genetic combinations are lost as uniform commercial crops are introduced.  相似文献   

19.

Key message

We present here the first curated collection of wild and cultivated African rice species. For that, we designed specific SNPs and were able to structure these very low diverse species.

Abstract

Oryza glaberrima, the cultivated African rice, is endemic from Africa. This species and its direct ancestor, O. barthii, are valuable tool for improvement of Asian rice O. sativa in terms of abiotic and biotic stress resistance. However, only a few limited studies about the genetic diversity of these species were performed. In the present paper, and for the first time at such extend, we genotyped 279 O. glaberrima, selected both for their impact in current breeding and for their geographical distribution, and 101 O. barthii, chosen based on their geographic origin, using a set of 235 SNPs specifically designed for African rice diversity. Using those data, we were able to structure the individuals from our sample in three populations for O. barthii, related to geography, and two populations in O. glaberrima; these two last populations cannot be linked however to any currently phenotyped trait. Moreover, we were also able to identify misclassification in O. glaberrima as well as in O. barthii and identified new form of O. sativa from the set of African varieties.  相似文献   

20.
The Thomel Level of the Lambruisse section in the Vocontian Basin (southeast France), which is marked by intercalations of black shales and organic-rich marls, accumulated during the oceanic anoxic event 2 (OAE2) occurring in the Cenomanian-Turonian (C-T) boundary interval. Calcareous nannofossil biostratigraphic investigation of this interval revealed a total of five nannofossil zones, corresponding to the UC3-UC8 zones (Middle Cenomanian-Middle Turonian) as defined by Burnett. Biostratigraphically important taxa observed in the section include Cretarhabdus striatus, Axopodorhabdus albianus, Lithraphidites acutus, Corollithion kennedyi, Helenea chiastia, Quadrum gartneri, Q. intermedium, Eiffellithus eximius, Eprolithus octopetalus and E. eptapetalus. The two nannofossil events commonly used in the delineation of the C-T boundary, namely the LO of H. chiastia and the FO of Q. gartneri, occur less than 2 m apart in the studied section. These two bioevents define the limits of the UC6 nannofossil Zone and occur within the Whiteinella archaeocretacea foraminifer Zone. Previous litho- and chemostratigraphic analyses indicate that the δ13C profile of the section corresponds well with changes in lithofacies and fluctuations in the total organic carbon (TOC) and calcium carbonate content of the section. Initial increase in the δ13C values occurs within the UC3-UC4a undifferentiated zone, coinciding with the onset of the deposition of the organic-rich sediments of the Thomel Level and a drastic decline in the CaCO3 values. The plateau of high δ13C values, on the other hand, occurs within the UC5 zone, between the LO of C. kennedyi and the LO of H. chiastia (and FO of Q. gartneri). This interval of high δ13C values also corresponds to the interval of high TOC and low CaCO3 values. The integrated nannofossil, planktonic foraminifer and δ13C data provide a precise biostratigraphic and chemostratigraphic framework of the C-T boundary in the Lambruisse section that can be used in future studies in the Vocontian Basin and allow correlations with other well-studied C-T boundary sections.  相似文献   

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