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1.
Abstract

Juniperus turbinata Guss. (Cupressaceae) is a threatened tree species occurring in the Mediterranean area. It is listed as a vulnerable species in the Red Book of Italian plants and its various communities are included in Annex I of the Habitats Directive 92/43/EEC as a priority habitat for conservation. During field investigations carried out to analyse the plant biodiversity of coastal habitats in southern Sicily, a new interesting population was found. This study aims to characterize this relevant new finding with a marked focus on demography and synecology of the plant community in question in order to define its habitat, assess its conservation status and propose conservation measures. Our data highlight that the juniper is characterized by low turnover population dynamics. In order to understand the role of J. turbinata in sandy soil communities of south-eastern Sicily, comparisons of 21 plots (relevés) with 25 established plots in south-eastern Sicily were carried out using cluster analysis and canonical component analysis. This has allowed three different plant communities with different ecological features to be identified.  相似文献   

2.
Habitat Directive is the core strategy of nature conservation in Europe aiming at halting biodiversity loss. In this study the results of the third Italian assessment regarding the conservation status (CS) of plants listed in the Habitat Directive (Flora of community interest—FCI) was presented. Data was collected from several sources related to plant distribution, population data, habitats and pressures. Following the official European procedure, all parameters were evaluated and combined to give the CS of each taxon in each biogeographical region of presence. A comparison between the recent Italian IUCN and Reporting assessments was performed in order to evaluate the consistency between these two assessments. The official EU checklist comprises 113 Italian plant taxa, 107 of which were examined in this study. Our results showed a critical situation with only 34% of favourable CS, while 50% were unfavourable (40% inadequate plus 10% bad) and 16% unknown, in particular in the Mediterranean bioregion, where the unfavourable assessments reach the 65%. The results of the Report were consistent with those of the IUCN assessment, in which 41.9% of plants were threatened with extinction. This report highlighted some benefits and criticisms at national level, but it may have a wider significance. Although a general advance of knowledge, a great effort is needed to reach the Habitats Directive goals. Despite the limited resources, monitoring activities needs to be improved in order to close information gaps for several plants. A positive outcome was the development of a specific national project funded by the Italian Ministry of Environment, with the ambitious target to set future monitoring activities for FCI and optimize monitoring efforts.  相似文献   

3.
We analyse and report a synthesis of a long-term project leading to the creation of a database of habitats of conservation interest in Tuscany (Italy). All available floristic and vegetation literature from 1960 to date and relating to the Tuscan territory, and all terrestrial and inland water (non-marine) Habitats of European Community Interest as listed in Annex I of the EU Habitats Directive present in Tuscany have been identified and taken into account. A total of 2,691 sites were attributed to 82 different conservation interest habitat types and were geo-localised and uploaded to the database. For each habitat site, threat and pressure factors are indicated and a quick expert-based assessment made on the basis of three parameters: rarity, vulnerability and a quality estimate. For the analysis, all database information was referred to a vectorial 10 × 10 km grid. The territorial distribution of habitats is discussed with respect to: the level of information available, the numbers of reports and the habitat-type concentration. The major threats and pressures affecting these Tuscan habitats are highlighted and discussed. Vegetation dynamics proved to be the most important natural/seminatural threat. Another important threat is invasion by/competition with other organisms, mainly invasive alien species. Among anthropic threats, the management of riparian and aquatic vegetation together with water management all strongly affect many habitat types with links to wetlands. Infrastructures, particularly those connected with tourism and recreation, are an important threat factor especially in coastal areas. Some positive effects of certain anthropic pressures are also illustrated. Lastly, some actions to improve habitat knowledge, evaluation and conservation are suggested.  相似文献   

4.
5.
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   

6.
Long-term preservation of habitats has become a cornerstone of modern conservation policies. As resources allocated to conservation actions are often limited, developing relevant prioritizing methods is necessary. Although many studies have been published on species prioritization, habitats have been the subject of less research. This study aims to develop a simple prioritization method suitable for habitats and appropriate to any typology. We analyzed literature to select criteria that would be the most accurate to rank habitats. Our final method consists in calculating a score based on four criteria: legal obligation, territorial responsibility, conservation condition and an extra criterion designed to fit local interests and objectives. The method is applied on habitats listed in Annex I of the Habitats Directive (92/43/EEC) on the territory of RESEDA-Flore, a network of stakeholders involved in the conservation of Mediterranean flora. Results highlight that dune habitats show the highest conservation values, while rocky habitats and caves obtain relatively low scores. At the top of the ranking, Mediterranean temporary ponds (3170), Dunes with Pinus pinea and/or Pinus pinaster forests (2270) and Coastal dunes with Juniperus spp. (2250) appear to be a high priority. These results can be used to design and implement habitat conservation strategies in the French Mediterranean.  相似文献   

7.
Improvements in biodiversity conservation are hampered by the lack of reporting on the effectiveness of conservation techniques and the organizations that implement them. Here we summarize the accomplishments and potential impact of the non-governmental organization, Island Conservation, which eradicates damaging invasive vertebrates from islands. Island Conservation has removed 54 populations of 10 invasive vertebrates from 35 islands totaling over 520 km2. These actions helped protect 233 populations of 181 insular endemic species and subspecies of plants and vertebrates and 258 populations of 54 species and subspecies of seabirds from the threat of local and global extinction. There were no reinvasions. One eradication attempt failed. These conservation actions and their apparent biodiversity impact demonstrate the potential of private organizations to protect biodiversity by eradicating invasive species from islands.  相似文献   

8.
The importance of in vitro tools to complement other ex situ methods for saving plants from extinction is more relevant than ever before. More than 50% of the world’s plant species are endemic to the 34 global biodiversity hotspots (GBHs), each holding at least 1,500 endemic plant species. In addition, a large number of small islands hold a number of endemic species on the brink of extinction. Conservation support concentrating more on these hotspots and small islands would significantly reduce the loss of species that is currently occurring. In the majority of these cases, the resources are either locally scarce or difficult to access for in vitro conservation to support other ex situ measures. Most island countries are small, and their geographical position is a stumbling block to initiate active partnerships with other countries when they need to use in vitro tools to rescue plants that produce recalcitrant seeds/spores or propagate only by vegetative means. However, many biodiversity hotspot countries have facilities and expertise, and they concentrate on their own flora for in vitro conservation programmes. For decades, because of the grave threat these plants face, the Conservation Biotechnology Unit, previously known as the Micropropagation Unit, at Royal Botanic Gardens Kew (RBG Kew) has been at the forefront of assisting countries to save their valuable biodiversity through both in situ and ex situ methods. Approaches mentioned here highlight work on recalcitrant ferns from GBHs and small islands. Source materials from recalcitrant species, either spore or seed and in some cases vegetative material, need to be used immediately after collection for tangible results in vitro. This becomes more difficult when only a few plants or small populations are left in the wild. The task becomes harder when available material is small in quantity, and there is greater restriction on the use of available genetic diversity in the wild. This paper highlights the importance of proper collection measures, in vitro culture procedures and cryopreservation and methods for the integrated conservation of threatened ferns from both GBHs and small islands. The importance of international networking to achieve these conservation goals also will be discussed.  相似文献   

9.
In the European Union, the Directive 92/43/EEC defines a number of species and habitats of community interest that are worthy to be preserved because in danger to disappear or because they are representative of the different European bio-geographical regions. In the light of the limited economic resources generally allocated to conservation efforts, there is the necessity to prioritise conservation actions in order to avoid deterioration of protected areas. To this aim, in the present study the most representative habitats of the Italian Alps are compared on the basis of vascular plant biodiversity and a conservation priority index is proposed for each habitat taking into account the potential distribution of 252 threatened vascular plant species. Rocky slopes, screes and alpine grasslands resulted to have the greatest percentage of endemic plant species so reflecting the general distributional pattern of endemic plant species at high altitudes in Eurasian mountains. The relationship between the conservation priority index and the corresponding habitat extent within the Natura 2000 network suggests that peatlands, arid grasslands, wet meadows and freshwater habitats deserve a higher priority in conservation actions. Although vascular plant biodiversity is not necessarily a surrogate of overall biodiversity of Alpine habitats, the results here reported can be used as an initial reference framework for prioritising conservation actions, so as to accomplish the provisions of Article 6 of Habitats Directive.  相似文献   

10.
The aim of this paper is to identify the habitat types listed in the Habitats Directive Annex I that require low-intensity agricultural management for their existence. We assessed the link between the Annex I habitat types and agricultural practices in order to identify habitat types that depend on the continuation of agricultural practices or whose existence is prolonged or spatially enlarged via blocking or reducing the secondary succession by agricultural activities. 63 habitat types that depend on or which can profit from agricultural activities—mainly grazing and mowing—were identified. They are classified into 2 groups: (1) habitats fully dependent on the continuation of agricultural management; (2) habitats partly dependent on the continuation of agricultural management. This paper also briefly discusses habitat types for which either doubts remain on their dependence on agricultural management, or the relation to extensive farming practices exists only in part of their area of distribution in Europe or under certain site conditions, respectively. Assessments of the conservation status of habitats of European Importance by 25 EU Member States in 2007 showed that habitats identified by us as depending on agricultural practices had a worse status than non-agricultural habitats.  相似文献   

11.
《PloS one》2015,10(3)
The identification of nursery grounds and other essential fish habitats of exploited stocks is a key requirement for the development of spatial conservation planning aimed at reducing the adverse impact of fishing on the exploited populations and ecosystems. The reduction in juvenile mortality is particularly relevant in the Mediterranean and is considered as one of the main prerequisites for the future sustainability of trawl fisheries. The distribution of nursery areas of 11 important commercial species of demersal fish and shellfish was analysed in the European Union Mediterranean waters using time series of bottom trawl survey data with the aim of identifying the most persistent recruitment areas. A high interspecific spatial overlap between nursery areas was mainly found along the shelf break of many different sectors of the Northern Mediterranean indicating a high potential for the implementation of conservation measures. Overlap of the nursery grounds with existing spatial fisheries management measures and trawl fisheries restricted areas was also investigated. Spatial analyses revealed considerable variation depending on species and associated habitat/depth preferences with increased protection seen in coastal nurseries and minimal protection seen for deeper nurseries (e.g. Parapenaeus longirostris 6%). This is partly attributed to existing environmental policy instruments (e.g. Habitats Directive and Mediterranean Regulation EC 1967/2006) aiming at minimising impacts on coastal priority habitats such as seagrass, coralligenous and maerl beds. The new knowledge on the distribution and persistence of demersal nurseries provided in this study can support the application of spatial conservation measures, such as the designation of no-take Marine Protected Areas in EU Mediterranean waters and their inclusion in a conservation network. The establishment of no-take zones will be consistent with the objectives of the Common Fisheries Policy applying the ecosystem approach to fisheries management and with the requirements of the Marine Strategy Framework Directive to maintain or achieve seafloor integrity and good environmental status.  相似文献   

12.
The protection of key areas for biodiversity at sea is not as widespread as on land and research investment is necessary to identify biodiversity hotspots in the open ocean. Spatially explicit conservation measures such as the creation of representative networks of marine protected areas (MPAs) is a critical step towards the conservation and management of marine ecosystems, as well as to improve public awareness. Conservation efforts in ecologically rich and threatened ecosystems are specially needed. This is particularly urgent for the Mediterranean marine biodiversity, which includes highly mobile marine vertebrates. Here, we studied the at sea distribution of one of the most endangered Mediterranean seabird, the critically endangered Balearic shearwater Puffinus mauretanicus. Present knowledge, from vessel-based surveys, suggests that this species has a coastal distribution over the productive Iberian shelf in relation to the distribution of their main prey, small pelagic fish. We used miniaturised satellite transmitters to determine the key marine areas of the southern population of Balearic shearwaters breeding on Eivissa and spot the spatial connections between breeding and key marine areas. Our tracking study indicates that Balearic shearwaters do not only forage along the Iberian continental shelf but also in more distant marine areas along the North African coast, in particular W of Algeria, but also NE coast of Morocco. Birds recurrently visit these shelf areas at the end of the breeding season. Species distribution modelling identified chlorophyll a as the most important environmental variable in defining those oceanographic features characterizing their key habitats in the western Mediterranean. We identified persistent oceanographic features across time series available in the study area and discuss our results within the current conservation scenario in relation to the ecology of the species.  相似文献   

13.
Depending on their faunal content islands can function as important ‘vehicles’ for conservation. In this study, we examine data on 440 butterfly species over 564 European islands in 10 island groups. To determine the status of the butterfly fauna, we have adopted two approaches, island-focused and species-focused, examined using principal components analysis and regression modelling. In the former, we relate species richness, rarity and endemicity to island geography (area, elevation, isolation and location in latitude and longitude); in the latter, species occurrence on islands is examined in relation to distribution, range, range boundaries, and altitudinal limits on the continent as well as species’ ecology (number of host plants) and morphology (wing expanse). Species on islands are also assessed for their status on the continental mainland, their distributional dynamics (extinctions, distribution changes) and conservation status (Red Data Book, European Habitat Directive, Species of European Conservation Concern and Bern Convention listing. Unexpectedly, we find that a large fraction of the European butterfly species is found on the islands (63.4%; 59% on small islands) comprising some 6.2% of the land area of Europe. Although species occurring on the islands tend, on the whole, to have lower conservation status and are not declining over Europe, 45 species are endemics restricted to the islands. Species richness shows only a weak locational pattern and is related as expected to isolation from the continental source and island area; but, both rarity and endemicity have distinctive geographical bias to southern Europe, on islands now under increasing pressure from climate change and increasingly intensive human exploitation. The vulnerability of species on islands is emphasised in the relationship of island occurrence (% occurrence and presence/absence of species on any island) with continental distributions. A large proportion of the variation (84%) is accounted by continental distribution, the southern range limit and lower altitudinal limit. Most species (69%) occur on very few islands (<5%). In view of ongoing species dynamics on islands, migrations and extinctions of species, island repositories of species depend in large part on conservation of butterflies at continental sources. The unique faunas and rare species on islands also depend on appropriate concern being given to the island faunas. Conservation of European islands is thus a two-way process, sustaining sources and conserving island refuges. Residuals from the regressions (islands with more or fewer species, rare and endemic species; species occurring more or less frequently than expected on islands) provide warning signals of regions and islands deserving immediate attention.  相似文献   

14.
Abstract

The collections stored at the Sardinian Germplasm Bank (BG-SAR) were analysed to verify if setting conservation priorities on the exclusive endemic flora of Sardinia (Italy) would make it possible to reach the 2010 GSPC Target 8. By 2010, 39.9% of the exclusive-endemics of Sardinia, 43.1% of the BGCI European threatened species and 65.0% of the taxa listed in Annex II of DIR 92/43/EEC present on the island had been stored in BG-SAR. Of the stored plants, 40% of those listed in the DIR 92/43/EEC, and only 25.69% of the BGCI threatened plants are represented by an adequate number of populations. For a few of the stored threatened plants (ca. 36%), and for 60% of the DIR 92/43/EEC ones, at least one seedlot with more than 5000 seeds is available. These data indicate that focusing on exclusive endemics gave a substantial, although not decisive, contribution towards the achievement of the 2010 GSPC Target 8 in Sardinia, and that more efforts are needed to guarantee the effective long-term conservation of these threatened taxa with the aim of reaching the 2020 GSPC target.  相似文献   

15.
Abstract

In the present study, species were selected from the new Red List of the vascular flora of Hungary which can be regarded as a weed. For each species, current conservation status and the most important traits were assessed. Altogether 149 weed species were found to be at risk according to the International Union for Conservation of Nature (IUCN) categories: 11 species are extinct, 11 are critically endangered, 27 are endangered, 26 are vulnerable, 62 are near threatened and 12 are data deficient. These species belong to 37 plant families, from which the most important are Caryophyllaceae, Brassicaceae, Asteraceae, Scrophulariaceae, Chenopodiaceae, Poaceae and Fabaceae. The most significant chorological elements are Mediterranean (28%) and Eurasian (27%); endemic (Pannonian) taxa constitute only 5.4%. Over 90% of these species are of native or archaeophyte origin, according to their residence time. Considering the main habitat types, 46% of the species are originated from dry habitats, 23% from arable lands, 17.5% from wet habitats and 13.5% from ruderal habitats. In the life form spectra, a pronounced dominance of therophytes (81%) is represented. The factor that currently offers the greatest conflict to the conservation of endangered weed species in Hungary are side effects of strong eradication campaigns against the invasive Ambrosia artemisiifolia.  相似文献   

16.
Cats are generalist predators that have been widely introduced to the world's ~179 000 islands. Once introduced to islands, cats prey on a variety of native species many of which lack evolved defenses against mammalian predators and can suffer severe population declines and even extinction. As islands house a disproportionate share of terrestrial biodiversity, the impacts of invasive cats on islands may have significant biodiversity impacts. Much of this threatened biodiversity can be protected by eradicating cats from islands. Information on the relative impacts of cats on different native species in different types of island ecosystems can increase the efficiency of this conservation tool. We reviewed feral cat impacts on native island vertebrates. Impacts of feral cats on vertebrates have been reported from at least 120 different islands on at least 175 vertebrates (25 reptiles, 123 birds, and 27 mammals), many of which are listed by the International Union for the Conservation of Nature. A meta‐analysis suggests that cat impacts were greatest on endemic species, particularly mammals and greater when non‐native prey species were also introduced. Feral cats on islands are responsible for at least 14% global bird, mammal, and reptile extinctions and are the principal threat to almost 8% of critically endangered birds, mammals, and reptiles.  相似文献   

17.
The Gargano is one of the richest Mediterranean areas in biodiversity. The work reports an assessment of the presence and conservation status of the habitats according to the 92/43/EEC Directive of Gargano coastal and low hill belts, their relationships with plant communities, threatened species, phytoclimatology, threats, and suggestions for management purposes. The field surveys revealed 33 habitats of Directive, and 6 of them are priority (1150* Coastal lagoons, 2250* Coastal dunes with Juniperus ssp., 2270* Wooded dunes with Pinus pinea and/or Pinus pinaster, 6220* pseudo-steppe with grasses and annuals of the Thero-Brachypodietea, 7210* Calcareous fens with Cladium mariscus and species of the Caricion davallianae, 91AA* Eastern white oak woods). The updates of six Special Areas Conservation and three Special Protection Areas of Natura 2000 network are provided.  相似文献   

18.
Conservation ecology is a new paradigm of ecology that aims at scientific contributions to maintaining earth's biodiversity and is committed to ecosystem management indispensable to intergenerational long-term sustainability. Population ecology plays a central role in conservation ecology. Persistence of the metapopulation rather than that of each local population should be pursued in species conservation management. Biological interactions essential to reproduction and soil seed bank components of the population should be investigated and applied to planning for the conservation of a plant population. Gravelly floodplains and moist tall grasslands are among typical riparian habitats containing many threatened plants in Japan. These riparian habitats are now subjected not only to heavy fragmentation but also to intensive invasion of highly competitive alien (nonnative) plants. Extreme habitat isolation may result in reproductive failure or fertility selection in a plant population without pollinators, as exemplified by a nature reserve population of Primula sieboldii. Biological invasions, which are facilitated by extensive changes in the river environment including decreased seasonal flooding, abandonment of traditional vegetation management, eutrophication, and extensive clearing of the land for recreational use, threaten endemic riparian species. To preserve safe sites and growing conditions for threatened plants such as Aster kantoensis, active management to suppress the dominance of alien invader plants is necessary. Population management and habitat restoration should be based on sound information on the population ecology of both threatened and alien invader plants, designed as an ecological experiment to clarify effective ways for management. Received: September 18, 1998 / Revised: October 22, 2001 / Accepted: October 23, 2001  相似文献   

19.
The UK has sovereignty over 16 Overseas Territories, which hold some of the world’s great seabird colonies and collectively support more endemic and globally threatened bird species than the whole of mainland Europe. Invasive alien mammalian predators have spread throughout most of the Territories, primarily since European expansion in the 16th century. Here we review and synthesize the scale of their impacts, historical and current, actions to reduce and reverse these impacts, and priorities for conservation. Mammalian predators have caused a catastrophic wave of extinctions and reductions in seabird colony size that mark the UKOTs as a major centre of global extinction. Mammal‐induced declines of threatened endemics and seabird colonies continue, with four Critically Endangered endemics on Gough Island (Tristan da Cunha), St Helena and Montserrat directly threatened by invasive alien House Mice Mus musculus, Feral Cats Felis catus and rats Rattus spp. Action to reduce these threats and restore islands has been modest in comparison with other developed countries, although some notable successes have occurred and a large number of ambitious eradication and conservation plans are in preparation. Priority islands for conservation action against mammalian predators include Gough (which according to one published prioritization scheme is the highest‐ranked island in the world for mammal eradication), St Helena and Montserrat, but also on Tristan da Cunha, Pitcairn and the Falkland Islands. Technical, financial and political will is required to push forward and fund the eradication of invasive mammalian predators on these islands, which would significantly reduce extinction risk for a number of globally threatened species.  相似文献   

20.
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