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The phytogeography of the genus Allium in Siberia and Mongolia is described, based on the numerical classification of a matrix of 56 species and 769 Operational Geographic Uniis (OGUs). Two main diversity centers can be detected, the Altai-Tuva region and southeastern Siberia, which can be further subdivided into 4 subcenters: Altai Mts., Tuva Mts., southern Baikal and Dahuria. The first three subcenters. located in southern Siberia, are rich in endemic species, which are mostly bound to semi-arid environments such as montane steppes and alpine vegetation. These old, isolated mountain ranges constitute the main refugial centers for the Allium flora of Siberia and Mongolia. The Tuva subcenter, rich in endemics and poor in polyploid species, seems to be the most conservative area; the south Baikal region, much richer in polyploid species, appears as an important center af speciation. 相似文献
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I Bruni F De Mattia S Martellos A Galimberti P Savadori M Casiraghi PL Nimis M Labra 《PloS one》2012,7(9):e43256
Background
Identification keys are decision trees which require the observation of one or more morphological characters of an organism at each step of the process. While modern digital keys can overcome several constraints of classical paper-printed keys, their performance is not error-free. Moreover, identification cannot be always achieved when a specimen lacks some morphological features (i.e. because of season, incomplete development or miss-collecting). DNA barcoding was proven to have great potential in plant identification, while it can be ineffective with some closely related taxa, in which the relatively brief evolutionary distance did not produce differences in the core-barcode sequences.Methodology/Principal Findings
In this paper, we investigated how the DNA barcoding can support the modern digital approaches to the identification of organisms, using as a case study a local flora, that of Mt. Valerio, a small hill near the centre of Trieste (NE Italy). The core barcode markers (plastidial rbcL and matK), plus the additional trnH-psbA region, were used to identify vascular plants specimens. The usefulness of DNA barcoding data in enhancing the performance of a digital identification key was tested on three independent simulated scenarios.Conclusions/Significance
Our results show that the core barcode markers univocally identify most species of our local flora (96%). The trnH-psbA data improve the discriminating power of DNA barcoding among closely related plant taxa. In the multiparametric digital key, DNA barcoding data improves the identification success rate; in our simulation, DNA data overcame the absence of some morphological features, reaching a correct identification for 100% of the species. FRIDA, the software used to generate the digital key, has the potential to combine different data sources: we propose to use this feature to include molecular data as well, creating an integrated identification system for plant biodiversity surveys. 相似文献4.
Checklists, the result of time-consuming exploration and painstaking bibliographic research, can be easily converted into online databases, which have the advantage of being updatable online in real time, and of reaching a much wider audience. However, thousands of local checklists (Natural Parks, protected areas, etc.) are still available on paper only, and most of those published online appear as dry lists of latin names, which strongly reduces their outreach for a wider audience. The University of Trieste has recently started the publication of several local checklists in a way that may be more appealing for the general public, by linking species'' names to archives of digital resources, and especially to digital identification tools produced by software FRIDA (FRiendly IDentificAtion). The query interfaces were developed on the basis of feedback from a wide range of users. The result is no longer a simple list of names accessible on the Web, but a veritable multimedial, interactive portal to the biodiversity of a given area. This paper provides an example of how relevant added value can be given to local lists of taxa by embedding them in a complex system of biodiversity-related resources, making them usable for a much wider audience than a restricted circle of specialists, as testified by the almost 1.000.000 unique visitors reached in 2014. A critical mass of digital resources is also put at disposal of the scientific community by releasing them under a Creative Commons license. 相似文献
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Pier Luigi Nimis 《Plant Ecology》1989,81(1-2):209-215
The phytogeography of a treeline Salix pulchra community from the northern Yukon is studied by means of classification and ordination on a matrix of species and Operational Geographic Units. The basic data were obtained from the global distributions of the species. Results suggest that this community is an example of pre-glacial treeline vegetation which survived in ice-free areas within ancient Beringia.Abbreviations OGV =
Operational Geographical Unit 相似文献
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Abstract This article describes the experience of project Dryades, coordinated by the University of Trieste, in developing interactive identification keys in the form of applications for mobile devices (iPhone/iPad/iPodtouch). All of our keys were previously generated from a database of morpho-anatomical characters using software FRIDA. The applications for mobile devices, which were tested Europe-wide during the project KeyToNature, have proved to be useful in education, in the promotion of nature-aware tourism and in projects of citizen science. The first-generation apps were stand-alone packages which consisted into a sequence of stand-alone HTML pages, while those of the second generation do incorporate the digital key as a true database into the mobile device. All of the hitherto published applications are basically in the form of illustrated dichotomous keys. Future developments will also include a multi-entry query interface, and will be extended to devices which use the Android system. 相似文献
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Stefano Martellos Michele Aleffi Roberta Tacchi Rodolfo Riccamboni Pier Luigi Nimis 《Plant biosystems》2013,147(3):529-535
The checklist of hornworts, liverworts and mosses of Italy is available online as a federated database, which can be queried by combining taxonomic and distributional information. Several digital identification keys have been included in the system, which will be part of the forthcoming Italian Biodiversity Network. 相似文献
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A complex database on the lichens of Italy was used to combine ecological indicator values assigned to each species (pH, eutrophication, light and aridity), in such a way as to simulate `virtual habitats' from a beech forest of northern Italy. For each habitat, a list of species was obtained (`virtual relevé'). A matrix of real and virtual relevés was submitted to classification and ordination, obtaining six main community-types, all of which include both real and virtual relevés. Two ordinations of species were carried out, one on the matrix of real relevés, the other on that of virtual relevés: their comparison shows that the consistency and the resolving power of the indicator values was high, but it also permits to detect and correct some errors. The results indicate a high predictivity of the indicator values for constructing ecological scenarios. 相似文献
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This study is based on the analysis of the chorological spectra from 19 vegetation types obtained from a numerical classification of ca. 400 phytosociological relevés taken during a vegetation survey in the Yukon Territory (NW Canada).All vegetation types are well characterized in terms of their chorological features. This allowed an ecological-historical interpretation of the vegetation in the study area. The distribution of the various chorological categories within the vegetation types is strongly correlated with the main environmental influences, whose action led to the present floristical and vegetational characteristics of the area, such as glaciation, fire, permafrost and water availability.The results show how the phytosociological approach constitutes an effective methodological tool for clarifying the phytogeographical aspects in the historical-ecological interpretation of a large area.Nomenclature follows Hultén (1968), otherwise author names are specified.The field work was completed in the summer of 1978. We are grateful to Dr W. Stanek, Canadian Forestry Service, for coordination of the survey and for soil data, and to Prof. L. Orlóci for organization. Partial financial support was received from the Italian C.N.R. 相似文献
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A minimum variance cluster analysis of 87 species of vascular plants occurring in south Siberian birch woodlands, based on their total distribution ranges, grouped them into 9 phytogeographic elements. The main distribution patterns of each element are illustrated by means of maps obtained by automatic mapping programs, showing the joint occurrence of the species of each element on a world scale. The results indicate a predominance of Eurasiatic-temperate taxa. The south Siberian birch woodlands can be considered as the easternmost extensions of the European deciduous forest belt, which in Siberia is compressed between the taiga biome in the north and the steppe biome in the south. The marginal position of Siberian Betula stands is reflected by the persistence of plants which are ecologically marginal with respect to true forest vegetation; most of the Eurasiatic species are typical, in Europe, of forest-meadows and forest-margins. 相似文献