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1.
The purpose of this study was to examine the composition, distribution, ecology, and conservation status of the Atlantic elements of the Swiss flora. About 195 Atlantic and 80 Mediterranean–Atlantic vascular plant species of the European flora have been used as the basis for our analysis. The complete list of 3,143 taxa has been used as the reference for the Swiss flora. The distributions of the species are illustrated in coincidence maps based on the computer database of the Data Centre of the Swiss Flora in Geneva, Switzerland. Our study demonstrates clearly that the Atlantic flora of Europe requires a new biogeographical appraisal. The Swiss flora comprises 66 Atlantic and Mediterranean–Atlantic taxa, which are taxonomically and ecologically highly diverse. Switzerland contains 44% of all European Sub-Atlantic plants. This confirms the Sub-Atlantic geographical position of Switzerland. Only one Eu-Atlantic species growing in Switzerland, Vicia orobus, can be classified as native with certainty. This species is critically endangered and merits the highest conservation priority. Although a very alpine country, Switzerland has a relatively large number of Mediterranean–Atlantic species. The Atlantic and Mediterranean–Atlantic plants are a very threatened group in Switzerland, with wetland plants the most imperilled ecological group. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

2.
ABSTRACT

Background

The genus Restrepia occurs throughout Central and South America in areas of montane forest heavily affected by deforestation.  相似文献   

3.
A comparative analysis of the habitats of Baldellia ranunculoides (subsp. ranunculoides and subsp. repens) and Baldellia alpestris (Alismataceae) was carried out across central and western Europe. Soil samples from 43 populations were analyzed and the composition of accompanying vegetation was analyzed by canonical correspondence and indicator species analysis. Significant differences in the habitat conditions and the accompanying vegetation were found between the three taxa. B. ranunculoides subsp. repens is growing in lowland water bodies on acidic substrates (pH 5–6.3) which are markedly richer in organic matter and poorer in cations, especially in Ca2+. B. ranunculoides s. str. is also a lowland taxon, but grows on more mineral and basic substrates (pH 7–9), usually rich in Ca2+. The endemic B. alpestris grows in the most distinct habitats, on substrates with low pH and with very low Ca2+ concentrations, at much higher altitudes than the other taxa and in very specific plant communities that have almost no affinities with those of the two lowland Baldellia-taxa. The Baldellia-taxa are threatened by eutrophication of their habitats. Moreover, many of the extant populations, in particular those of B. ranunculoides s. str., are very small and will be threatened by environmental stochasticity. Reintroduction and the creation of new populations might reduce the risk of extinction. Information given on the detailed habitat preferences of the Baldellia-taxa could help conservation efforts for these endangered taxa and identify suitable sites for (re-) introductions.  相似文献   

4.
Aquatic plants, and especially the emblematic genus Baldellia (Alismataceae), are among the most threatened organisms, due to unprecedented human-driven habitat destructions. Therefore protection plans are crucially needed and call for thoroughly documenting the genetic diversity and clarifying the taxonomy of this endangered genus. Our sampling included 282 individuals from 42 natural populations and covered the whole geographical range of the genus, across Europe and the Mediterranean. We combined sequencing of nuclear internal transcribed spacer (ITS) and chloroplastic trnL-ndhF regions with amplified fragment length polymorphism (AFLP) genotyping to investigate the Alismataceae phylogeny, and produce a phylogeography of Baldellia. Our phylogeny strongly supported the monophyly of Baldellia and placed it as the sister clade to Luronium and Alisma, therefore excluding, as previously supposed, a close genetic relatedness to the predominantly neotropical genus Echinodorus. The phylogeography of Baldellia outlined patterns consistent with a hypothesis considering glacial refugia located in the Iberian Peninsula and the Italy/Balkan region from which two distinct genetic lineages re-colonized Europe. These two lineages corresponded respectively to Baldellia ranunculoides (Italy/Balkan derived populations) and Baldellia repens (populations recovered from the Iberian Peninsula refuge), therefore supporting differences outlined between the two taxa in previous ecological and morphological studies. These results allowed clarifying taxonomic uncertainties by confirming the genetic distinctness of B. repens according to B. ranunculoides. A third lineage, Baldellia alpestris, originated and remained endemic to the mountainous regions of the Iberian Peninsula. Unexpectedly, B. repens populations collected in northern Africa, appeared to be genetically distinct from their European counterparts, this calls for further investigation to fully address their genetic and conservation status. Finally, we detected a large hybridization zone in northwestern Europe between B. repens and B. ranunculoides. These results were discussed in light of conservation approaches for Baldellia populations.  相似文献   

5.
This article compares amphibian and reptile components of the original and revised versions of the Red List of Japan, and analyzes geographic patterns of, and major threats to, species and subspecies now assigned to the threatened categories. The numbers of both amphibians and reptiles categorized as threatened in the Red List of Japan have increased greatly through its revision as a result of recent progress in the taxonomy of these groups in Japan, the introduction of new criteria for risk assessment, and unexpectedly rapid declines in the status of several taxa. Threatened taxa of amphibians and reptiles in the revised list tend to be concentrated in the Ryukyu Archipelago, where deforestation seems to be the major ultimate cause of declines. Reduction in the quality and quantity of inland water environments seems to be the major cause of declines in several endemic amphibians from the main islands of Japan. The importance of conservation was emphasized in the revised list by progress in taxonomy, by new insights and data on the estimation of temporal dynamics of population density or habitat size for threatened taxa, and by the impacts of and need to prevent further deforestation in the Ryukyus and of the ongoing destruction of inland water habitats on the main islands of Japan. Received: May 6, 1999 / Accepted: October 26, 1999  相似文献   

6.
The Desertas Islands (Madeira, Portugal) are the sole home of one of the largest and rarest wolf spider species, Hogna ingens (Blackwall 1857) (Araneae, Lycosidae). Despite its size, it inhabits a single valley in the North of the Deserta Grande Island, Vale da Castanheira, currently invaded by the herb Phalaris aquatica. This invasive species competes with the native flora and was subject to several eradication experiments, namely through fire and chemicals. The objectives of this work were to: (1) estimate the current distribution and abundance of H. ingens and respective trends; (2) evaluate the impact of the invasive plant and eradication methods on the spider population; (3) suggest future measures for the recovery of the species; and (4) evaluate its conservation status according to the IUCN criteria.The current distribution of H. ingens covers 23 ha, a recent reduction from its original 83 ha, corresponding to the entire Vale da Castanheira. A total of 4447 and 4086 adults and 71,832 and 24,635 juveniles were estimated to live in the valley during 2011 and 2012, respectively. We found a significant negative impact of P. aquatica cover on the presence and abundance of H. ingens and that chemical treatment specifically directed towards the invasive plant species may be the only way to effectively recover the spider's habitat. We suggest (1) regular monitoring; (2) extend chemical treatments; (3) ex-situ conservation with future reintroduction of adults. Based on the current area of occupancy (AOO) of H. ingens and its recent decline in both AOO and number of individuals, it was recently classified as Critically Endangered by IUCN and we suggest its urgent inclusion in the Habitats Directive species lists.  相似文献   

7.
We investigated aquatic plant diversity by conducting the field investigation and collecting the published data in the arid regions of Northwest China. Two hundred and twenty four taxa of vascular aquatic plants representing 64 genera and 34 families occur in this area, 8.48% of which are endemic. Among these, 1 genus and 6 species were new state records and 1 family, 9 genera and 29 species were new area records. Typhaceae, Potamogetonaceae, Juncaginaceae and Haloragaceae were the most frequent families (considering relative frequency of occurrence), whereas Cyperaceae, Potamogetonaceae and Ranuncnlaceae are the most species-rich. The most frequent genera were Typha, Potamogeton, and Triglochin, and the most species-rich were Potamogeton, Eleocharis and Scirpus. The most frequent species are Triglochin palustre, Myriophyllum spicatum, Potamogeton pectinatus and Typha angustifolia. Aquatic plants diversity is distributed unevenly in the region. The maximum species occurs in Dzungarian basin while the least species in Hexi corridor. The aquatic flora in arid zone of China is not distinctive although some endemic species are found, most species are widely distributed. Local aquatic plants diversity can be influenced by many factors such as hydrological alteration, habitat loss, over-grazing, high human population pressure, global climate change, an inappropriate economic development policy. Among them, the largest threat to aquatic plants biodiversity may be habitat loss due to hydrological alteration. In order to conserve the aquatic plants biological resources and biodiversity in this region, some strategies and measures must be suggested including strengthening scientific research and biodiversity education in the local people, balancing economic development and ecological conservation, and enhancing governmental assistance and subsidy to the local residents.  相似文献   

8.
Abstract

The genus Baldellia Parl. has always been a complex taxon. Three species and three subspecies have been proposed for the Iberian Peninsula. The morphological variation of this genus in the Iberian Peninsula, Balearic islands and northern Morocco, and its thermo-pluviometric and altitudinal correlation are the focus of this contribution. Twenty-eight morphological variables were examined and subjected to a multivariate statistical analysis. The three morphotypes observed (Form 1, which includes B. ranunculoides subsp. repens and B. alpestris; Form 2, which includes B. ranunculoides and Form 3 – for the new combination B. ranunculoides subsp. ranunculoides var. tangerina (Pau) J. Rocha, A. Crespí, M. García-Barriuso, R. Almeida, J. Honrado, comb. nova proposed here for the first time) seem to represent different reproductive strategies. Morphological variables related with the presence or absence of stolons and the architecture of the inflorescence; the size and number of fruits are the most discriminating variables. Form 1 represents the asexual morphotype; Forms 2 and 3 correspond to morphotypes for which sexual reproduction is preferential. The environmental approach revealed that the asexual form (Form 1) grows in temperate, in more humid conditions, and within a broad altitudinal range. In contrast, the two sexual forms are more common in warmer and drier conditions, and occur over a narrower interval of altitudes.  相似文献   

9.
De Silva et al . (2007) present an overview of the distribution and conservation status of the endemic freshwater fish of Asia. Within that review they use data from the IUCN Red List of Threatened Species™ (2006) to conduct an analysis of the conservation status of those endemic fish species. Their analysis is incorrect and provides a very misleading impression of the level of threat to Asian freshwater fish and to freshwater fish at the global scale. The errors stem from a misinterpretation of the data presented on the IUCN Red List. The sources of errors are discussed below and the opportunity is taken to clarify what the information on the IUCN Red List represents.  相似文献   

10.
Tulipa cypria, a Cyprus endemic plant, is protected under local and international legislations and categorised as “Endangered” by IUCN. Detailed habitat and distribution information was previously limited, particularly for northern Cyprus. Our objective was to accurately map the distribution and to collect habitat, subpopulation and threat data to enable a conservation status reassessment at global and regional levels. We gathered all available data and conducted extensive surveys focusing on northern Cyprus in 2014–2015, identifying 17 extant subpopulations amounting to 7765 individuals and the loss of 2 historical subpopulations amounting to 3500 individuals. We infer a continuous decline in population size and identify the major cause to be habitat loss through agriculture, with 75% of global habitats and 100% of northern Cyprus habitats being affected by it. We update the global assessment to Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v) and suggest regional assessments for northern Cyprus (Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v)), UN Buffer Zone (Endangered D1) and southern Cyprus (Endangered B2ab(iii)). Conservation priorities identified include initiation of gene transfer and life history studies, population trend monitoring and exsitu conservation actions.  相似文献   

11.
Although habitat destruction and the introduction of exotic species are causing the extinction of many native species, the number of extinct species that are then rediscovered is surprising. However, before searching for meaning of rediscoveries, we should distinguish between a false and a true rediscovery to avoid the interpretation of changes in biodiversity knowledge as changes in the efforts to conserve biodiversity. Here, we proposed the hypothesis of the biodiversity knowledge gap and a conceptual scheme to test this hypothesis, discussing how to deal with the rediscovery of a putatively extinct species. In this paper, we dealt with the local rediscovery of the plant Neptunia pubescens Benth. (Fabaceae), hypothesizing that if its local rediscovery is a case of the biodiversity knowledge gap (false rediscovery), its conservation status will change. Furthermore, we provided taxonomic data, geographic coordinates and figures as support for its local rediscovery, as well as some considerations about the implications for the conservation of N. pubescens.  相似文献   

12.
The Global Strategy for Plant Conservation calls for a preliminary assessment of the conservation status of all known plant species by the year 2010. To date insufficient progress has been made on meeting this target. New efforts to develop a preliminary list beyond using the full IUCN criteria in plant assessments are needed. Here we present an algorithm that provides a preliminary assessment of the conservation status of plant species using data from herbarium specimens. We use Hawaiian specimen data from the United States National Herbarium to calibrate the parameters of the algorithm and then use specimen data from the Arecaceae, Commelinaceae, Gesneriaceae and Heliconiaceae as examples of the application of the algorithm. The algorithm was calibrated to insure 95% accuracy in placing the Hawaiian plant species into previously and independently determined threatened categories. Our results indicate that 28% of the Hawaiian taxa, 27% of the species of Arecaceae, 45% of the species of Commelinaceae, 32% of the species of Gesneriaceae, and 35% of the species of Heliconiaceae are Not Threatened and will not need any further evaluation for the preliminary assessment. Species identified here as Potentially Extinct and Potentially Threatened can be further assessed by additional herbarium material and/or conservation specialists for final evaluation using other assessment strategies (e.g., regional and national lists, taxonomic expert assessment, etc.).  相似文献   

13.
A nucleotide sequence analysis of a portion of the mitochondrial large ribosomal subunit was performed to define the phylogeography of the threatened crayfish Austropotamobius (Decapoda; Astacidae) in Italy. We collected 61 specimens from 31 localities across the Italian peninsula. For the phylogenetic inference, we combined the 61 Austropotamobius spp sequences obtained from this study with 18 sequences deposited in GenBank and corresponding to Italian, French, Irish, Swiss, and Slovenian locations. Among the analysed sequences, 34 distinct haplotypes were detected. Our results confirmed the presence of both A. pallipes and A. italicus in the Italian peninsula and the existence within the latter species of a strong intraspecific genetic variation, due to the occurrence of four subspecies with a well-defined geographic distribution. From a conservation viewpoint, Italy, with its high haplotype variability, may be considered a 'hot spot' for the genetic diversity of the European native crayfish Austropotamobius. We suggest that re-introduction programs should be conducted with extreme caution in Italy, since not only the two Austropotamobius species but also the four A. italicus subspecies are genetically and taxonomically separate units and require independent conservation plans.  相似文献   

14.
In the period 1995–2006, the biodiversity of the aquatic habitats in the area of Serbia was explored, with the aim to identify the endangered species of macroalgae, macroinvertebratae and fishes. During the work a data base was formed (Aquatic Ecosystems Diversity in Serbia, AEDSer), containing the data from exploring the biodiversity of the aquatic ecosystems of Serbia since 1860. Based on the data base, classification of the aquatic species was made into categories of endangerment based on IUCN criteria. The following was noted: (1) the global IUCN category assigned to the species often is not identical with the national status of endangerment; and (2) the species that are given a category of endangerment at the national level do not have the same realistic risk of extinction in all their habitats. This remark imposed the need for a model for assessing the critical risk of extinction of the endangered species and determining the priorities of their protection at the national level. Two categories of characters were used to develop the model: the characters that determine the degree of ecological specialisation of the species based on the circumstances of habitat; and the characters suggesting the risk factors from the system: “HIPPO” in the spatial and time dimension. The possibility to apply the model was tested on 10 aquatic species belonging to different categories of endangerment at the national level (macroalgae 2, macroinvertebrates 7, and fishes 1 species). The model based on points determined the level of extinction risk and, that way, the species needing urgent conservation from the same or different categories of endangerment were isolated. The model suggested can contribute to a more efficient defining the conservation priorities.  相似文献   

15.
The mountain tapir Tapirus pinchaque is one of the largest and most threatened mammals of the northern South American Andes. It is distributed in montane forests and paramos mainly above 2000 m, from Colombia to north Peru. The species is categorised as globally Endangered and is mainly threatened by habitat degradation, habitat loss and fragmentation. Although up-to-date information is lacking in Peru on its distribution, population and conservation status, this population could play an important part in the global persistence of the species. We compiled all known recent occurrence records for the species from Peru, as well as data from camera traps with an effort of over 10,000 camera/days between 2016 and 2018. We modelled the tapir’s distribution using remote-sensed vegetation indices, topographic and bioclimatic variables in MaxEnt, followed by post-processing steps to remove unoccupied areas, to produce a current range map for the species in Peru. We overlaid this with spatial information on threats and protected areas. We estimate a range of almost 183,000 ha in Peru, in two main regions, north and south of the Huancabamba river, of which approximately 60% is within protected areas. However, protection gaps still exist, especially in the south of its range. Mining concessions cover 27% of its current range and we estimate 28,000 ha of forest loss within its extent of occurrence between 2001 and 2020. We provide recommendations for its conservation, including priority areas for increased protection, binational initiatives to ensure connectivity with populations in Ecuador and to use the tapir as a flagship species in efforts to protect montane ecosystems for water conservation.  相似文献   

16.
Ecological niche models (ENMs) have a wide range of biological applications, particularly in conservation. To build these models, two sources of information are needed: occurrence records for the species of interest and environmental variables. However, taxonomic limits are often unclear, and the selection of occurrence data depends on the species concept being used. In this study we generated ENMs based on different taxonomic levels within the Dendrortyx group, which is comprised of three species and several subspecies; we analyzed the geographic and ecological distribution patterns and discuss the implications for the biogeography and conservation of this group. Our results suggest that the area with suitable climate depends on the taxonomic category used in the model, which in turn affects the interpretation of the importance of different biogeographic barriers and introduces variation into the potential differentiation of Dendrortyx. In terms of conservation, Dendrortyx macroura and Dendrortyx leucophrys are in a low risk category, that of “least concern,” although they may be amended to a higher category when their allopatric lineages are considered as the units for modeling. We suggest carrying out an a priori taxonomic analysis to facilitate the empirical identification of the units to be modeled in order to allow for a better ecological and biogeographic interpretation and more sound conservation policies.  相似文献   

17.
The objective of this study was to identify the impact of nutrient enrichment on the diversity of the ciliate community associated with the roots of the aquatic macrophyte Eichhornia crassipes. The experiment was performed in the Garças Lake, located in the Upper Paraná River floodplain, Brazil. We conducted two treatments (fertilized and control) with three replicates each. To increase the initial nutrient concentrations in each mesocosm of the fertilized treatment, we added 1000 μg L−1 of KNO3 and 200 μg L−1 of KH2PO4 during each sampling date. We found a relative high number of ciliate species (85 species) and a predominance of hypotrichs. Among the recorded species, about 25% occurred exclusively in the fertilized treatment. Moreover, detrended correspondence analysis demonstrated that the ciliate community associated with E. crassipes roots changed significantly in response to the nutrient input in such a way that the species composition of the fertilized treatment was remarkably different from that of the control. In contrast to our expectations, species richness in the fertilized treatment was significantly higher than that in the control, refuting our hypothesis that species richness decreases under eutrophic conditions.  相似文献   

18.
On oceanic islands, the evolution of plants and animals with particular characteristics is favoured due to their isolation, populations normally comprising a large number of unique, endemic species. The Madeira and Selvagens archipelagos are considered biodiversity hotspots, containing an especially rich bryoflora. Due to its characteristically small size, this taxonomic group does not get much attention in conservation programmes. However, these plants are an important component of terrestrial ecosystems, representing a major part of biodiversity and playing a vital role in the ecosystem's functioning. As such, the development of the first Red List for Madeira and Selvagens Archipelagos has the potential to guide conservation efforts focused on taxa and habitats where threatened species and endemics are better represented. By applying the International Union for Conservation of Nature and Natural Resources (IUCN) criteria, recently revised to apply to small islands, it was possible to obtain the percentage of threatened taxa present in the archipelagos (23.6%), and for each habitat type. It was verified that high mountain habitats and the Laurel forest represent areas that host higher percentages of threatened taxa (29.5% and 22.2%). An important result of the present Red List is the identification of hotspots for bryophyte diversity, supporting the definition of reserves/microreserves. The information obtained can also be linked up with the Red Lists of other taxonomic groups to work towards the definition of a more holistic conservation strategy.  相似文献   

19.
Abstract

The narrow central Italian endemic and threatened Webb’s hyacinth (Bellevalia webbiana), a perennial herb, is a clear example of a species that has disappeared from several localities due to the development of human settlements. We characterized population genetics of this species to infer possible threats to its viability. We used a dominant DNA fingerprinting approach to infer genetic relationships among the five richest populations known for this species (each with N?>?50 individuals). We highlighted phenomena of genetic erosion, with values of intrapopulation-gene-diversity quite similar across all populations (mean value 0.113), but a mean F st value only slightly below the mean found in other plant species using similar approaches. Despite an overall genetic similarity among populations, a population from Faenza (Emilia-Romagna) is clearly separated from all the others on genetic grounds, and may be defined as an Evolutionarily Significant Unit, worth of special conservation attention. Interestingly, this latter population is also behaving differently from all the others in terms of both vegetative and reproductive functional strategies. Our results highlight the relevance of evolutionary approaches to conservation biology for preserving a genetic diversity linked to local adaptations.  相似文献   

20.
Field survey conducted to understand habitat, distribution, population structure and conservation status of Lilium polyphyllum. Three populations (total 649 individuals) are in decline because of habitat degradation, agriculture invasion and over exploitation. Our finding confirmed critically endangered status of the species, although with new criteria. We recommended integrated conservation plan.  相似文献   

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