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1.
In Italy, Platanus orientalis L. is judged as an endangered species by some authors and non-native by others: these contrasting assessments can mislead the prioritization of management actions to preserve the species and the riparian vegetation that is its host. Based on a multidisciplinary approach, including palaeobotanical and ecological information, we assessed its status in Italy including the ecological and conservation value of the riparian plant communities hosting it in the Cilento National Park (S-Italy). Palaeobotanical data showed that P. orientalis in Italy should be considered an archaeophyte. According to the ecological assessment of the riparian plant communities hosting P. orientalis, the presence of the species can be interpreted as an indicator of an unfavourable state for the conservation of riparian vegetation. Knowing the status of a species remains one of the first steps to take to correctly propose scientifically based solutions for the conservation of plant diversity. However, there are no absolute criteria for conservation because all conservation objectives can be considered as cultural values. In this context, P. orientalis should be protected as a symbolic tree, an archaeophyte testifying an ancient common Mediterranean cultural heritage, worthy of preservation but outside of natural habitats.  相似文献   

2.
The importance of plant communities for conservation purposes is recognized in their inclusion in the “Habitat Directive” (92/43 EEC), that relates habitat types to plant community syntaxonomic units. However, habitat definitions in the Habitat Directive lead to several inaccuracies in local habitat characterization. Several wetland plant communities (and their corresponding habitats), rare in the Mediterranean basin, are not included in the Habitat Directive. This study proposes criteria for assessing the conservation importance of habitats. It deals with plant community types at the alliance level, as promising units for setting conservation priorities. The principle criteria considered as drivers for setting alliance conservation values are the distribution and abundance of plant species of conservation interest and their fidelity to a plant community. Multivariate methods were used, and a quantitative floristic index of alliance conservation priority was created. This procedure was applied to an important wetland in central Italy. Results emphasize: (i) high conservation values of some alliances not listed in the Habitat Directive, confirming various gaps in the current conservation law affecting Mediterranean wetlands; (ii) that habitats widely distributed in other biogeographical areas, may greatly underestimate their conservation importance in Mediterranean region; (iii) need to consider regional peculiarities when setting conservation priorities.  相似文献   

3.
Phylogenetic, genetic and demographic information are key issues for establishing priorities for conservation. In this study we explored the Vane-Wrigth measure of phylogenetic diversity for establishing criteria for conservation, when intra as well as interpopulation level demographic (population size) and genetic (heterozygosity, inbreeding and genetic distances among populations) parameters are taken into consideration. The data were standardized and analyzed independently and integratively enabling the calculation of indices or criteria for conservation priorities. We illustrate the application of this approach in populations of four Mexican pine species that have been considered rare and endangered, Pinus rzedowzkii, P. pinceana, P. lagunae and P. muricata. The application of several independent diversity indices did not allow us to resolve prioritization. However, the integration of all indices generated different values of importance to conservation, and suggested that the populations with the highest priorities for conservation are: two for Pinus rzedowskii, P. pinceana, and P. lagunae, and one for P. muricata. These populations have intermediate sizes, are the most divergent in the phylogeny and contain genetic variation that is representative of the gene pool of each species. Finally, we demonstrated the functionality of some genetic and demographic parameters; the genetic structure, recruitment rate, geographic distribution and demographic stochasticity, as complementary indicators for evaluating the conservation priority among populations and species.  相似文献   

4.

Background

Coral reefs have exceptional biodiversity, support the livelihoods of millions of people, and are threatened by multiple human activities on land (e.g. farming) and in the sea (e.g. overfishing). Most conservation efforts occur at local scales and, when effective, can increase the resilience of coral reefs to global threats such as climate change (e.g. warming water and ocean acidification). Limited resources for conservation require that we efficiently prioritize where and how to best sustain coral reef ecosystems.

Methodology/Principal Findings

Here we develop the first prioritization approach that can guide regional-scale conservation investments in land- and sea-based conservation actions that cost-effectively mitigate threats to coral reefs, and apply it to the Coral Triangle, an area of significant global attention and funding. Using information on threats to marine ecosystems, effectiveness of management actions at abating threats, and the management and opportunity costs of actions, we calculate the rate of return on investment in two conservation actions in sixteen ecoregions. We discover that marine conservation almost always trumps terrestrial conservation within any ecoregion, but terrestrial conservation in one ecoregion can be a better investment than marine conservation in another. We show how these results could be used to allocate a limited budget for conservation and compare them to priorities based on individual criteria.

Conclusions/Significance

Previous prioritization approaches do not consider both land and sea-based threats or the socioeconomic costs of conserving coral reefs. A simple and transparent approach like ours is essential to support effective coral reef conservation decisions in a large and diverse region like the Coral Triangle, but can be applied at any scale and to other marine ecosystems.  相似文献   

5.
In the Mediterranean Sea, as well as in other parts of the word, intense bottom trawling threatens deep and mesophotic assemblages, compromising mainly the survivorship of erect organisms and of the habitat complexity they shape. Protection of species able to affect their habitats, by increasing spatial complexity and enhancing interspecific interactions, is crucial for biodiversity conservation. It is urgent to highlight the occurrence of those species which act as ecosystem engineers and/or habitat former to enhance awareness on their ecological role and to develop focused conservation strategies. Lytocarpia myriophyllum is the largest Leptomedusan hydroid of the Mediterranean Sea, with colonies up to 1 m high, and the most abundant Aglaopheniid in the eastern part of the North Atlantic Ocean. This species creates wide forests on soft bottoms stabilizing sediments, providing refuge and food for several other associated organisms and could be defined both a habitat former and an ecosystem engineer. Thanks to trimix diving here we report on new insights on the morphological, biological and ecological features of L. myriophyllum meadows from the Mediterranean Sea furnishing a baseline for protection plans focused on these facies. This work demonstrates that direct studies of mesophotic habitats allow to collect far more detailed information than grabs, ROVs, or towed camera arrays and highlights the urgent need to redefine the vertical extension of several marine protected areas.  相似文献   

6.
We present here the results of a first study comparing modern soil phytolith assemblages with pollen and botanical data at a North Mediterranean site. This work has shown the following limitations and advantages of phytolith analysis for the reconstruction of Mediterranean vegetation:(1) Phytoliths are produced in sufficient quantities for analysis and are well preserved in limestone environments, widespread in the Mediterranean area. (2) Young stands of Quercus ilex and Quercus coccifera, widely distributed in the Mediterranean area do not produce characteristic phytolith types in sufficient quantities to allow the calculation of a reliable index of tree cover density. (3) Pine forests, dominated by Pinus halepensis and Pinus sylvestris, are not recorded in the studied phytolith assemblages. (4) Grassland and shrubland assemblages can be distinguished through their associated phytolith assemblages, in particular by the proportion of crenate phytoliths produced in the short cells of the grass epidermis. (5) The different vegetation groups on the massif cannot be distinguished by pollen analysis. Further studies, comparing modern phytolith assemblages and quantitative vegetation data, should be carried out on forest plots that have been established for several centuries to further assess the role of phytolith analysis in vegetation reconstructions in the Mediterranean region.  相似文献   

7.
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   

8.
《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   

9.

Background

Adaptive radiation in Mediterranean plants is poorly understood. The white-flowered Cistus lineage consists of 12 species primarily distributed in Mediterranean habitats and is herein subject to analysis.

Methodology/Principal Findings

We conducted a “total evidence” analysis combining nuclear (ncpGS, ITS) and plastid (trnL-trnF, trnK-matK, trnS-trnG, rbcL) DNA sequences and using MP and BI to test the hypothesis of radiation as suggested by previous phylogenetic results. One of the five well-supported lineages of the Cistus-Halimium complex, the white-flowered Cistus lineage, comprises the higher number of species (12) and is monophyletic. Molecular dating estimates a Mid Pleistocene (1.04±0.25 Ma) diversification of the white-flowered lineage into two groups (C. clusii and C. salviifolius lineages), which display asymmetric characteristics: number of species (2 vs. 10), leaf morphologies (linear vs. linear to ovate), floral characteristics (small, three-sepalled vs. small to large, three- or five-sepalled flowers) and ecological attributes (low-land vs. low-land to mountain environments). A positive phenotype-environment correlation has been detected by historical reconstructions of morphological traits (leaf shape, leaf labdanum content and leaf pubescence). Ecological evidence indicates that modifications of leaf shape and size, coupled with differences in labdanum secretion and pubescence density, appear to be related to success of new species in different Mediterranean habitats.

Conclusions/Significance

The observation that radiation in the Cistus salviifolius lineage has been accompanied by the emergence of divergent leaf traits (such as shape, pubescence and labdanum secretion) in different environments suggets that radiation in the group has been adaptive. Here we argued that the diverse ecological conditions of Mediterranean habitats played a key role in directing the evolution of alternative leaf strategies in this plant group. Key innovation of morphological characteristics is supported by our dated phylogeny, in which a Mediterranean climate establishment (2.8 Ma) predated the adaptive radiation of the white-flowered Cistus.  相似文献   

10.
Species prioritization for conservation is primarily based on extinction risk assessments but less on sociocultural factors that influence conservation effectiveness. Here, we prioritized mammals for conservation according to their need for conservation attention, the feasibility of their conservation, and their potential to be used as flagship species in a rural community in northeast Brazil. We assessed species occurrence and ethnobiology through interviews, camera trapping, and active searches, and developed a prioritization scheme that accounts for species’ threat level (conservation status and local hunting pressure), cultural importance, and popularity. We found Tolypeutes tricinctus as the overall top-priority species because of its Endangered status and high popularity, which makes its conservation needed and feasible, and this species a potential conservation flagship. Panthera onca was the highest priority regarding the need for conservation attention due to its Critically Endangered status but the least feasible to conserve as it was the most unpopular species. Mazama gouazoubira was the most hunted and popular species. Despite not being threatened, it may also be prioritized for conservation, given its high hunting pressure and popularity, thereby constituting a possible local flagship species. Our results show that priority species for conservation can be reliably identified based on measures of need for conservation attention and expected conservation feasibility in local scales using rapid assessments. Accounting for ethnobiology in species prioritization for conservation allows a better understanding of the needs, opportunities, and obstacles for their conservation, consequently leading to better resource-allocation decisions in different socio-economic scenarios.  相似文献   

11.
Pinus halepensis Mill. is a common forest species in the Mediterranean area and it is important for environmental conservation. This study established a method of regenerating Pinus halepensis Mill. through somatic embryogenesis. The effect of culture medium (mineral salts, nitrogen source and plant growth regulators), collection date and seed family on embryogenic tissue initiation and proliferation in Pinus halepensis was analysed during the first steps of embryogenesis process. This study showed a marked effect of the culture medium tested as well as some significant differences among collection dates. Furthermore, the embryogenic tissue initiation was affected by the amino acid mixture in the culture medium and the proliferation stage was significantly affected by the combination of plant growth regulators. At the end of the maturation phase the presence of activated charcoal was also evaluated. Finally, maturation of embryogenic tissue was affected by the nitrogen source in the culture medium and these results were different for high and low mature embryo producing cell lines. To the best of our knowledge, this is the first report on Aleppo pine somatic embryogenesis describing a simple and efficient procedure for large-scale somatic embryo production.  相似文献   

12.
Alien species can represent a threat to several ecosystems because they can alter species relationships and ecosystem function. In Italy, Acacia saligna is a major invader and it forms dense stands in coastal environments. We analyze the impact of A. saligna in Italian Mediterranean dune systems. We randomly sampled coastal dune vegetation and investigated its floristic composition with ordination techniques. We compared species richness in invaded and non-invaded plots with rarefaction curves and analyzed the frequency of focal and ruderal species. A. saligna invaded Mediterranean scrub (habitats 2250* and 2260) and coastal Pinus dune wood (habitat 2270*) and it is particularly prevalent in sunny areas of habitat 2270*. We observed an increase in ruderal species and a decrease in focal species in the invaded plots of habitat 2270*. We suggest that more open and disturbed areas are more prone to A. saligna invasion.  相似文献   

13.
Terrestrial flatworms, or Terricola, are sensitive to environmentalchanges and therefore might be excellent indicators of the conservation statusof natural habitats. The present study aimed to answer two main questions: (1)is terrestrial planarian diversity affected by human disturbances, and (2) isthere any species or group of species that indicates such disturbance? The studysite, National Forest of São Francisco de Paula, Brazil, was originallycovered by a mixed ombrophilous forest, but successive reforestations andselective logging have modified the original landscape. We studied Terricoladiversity in the four main habitats in the study area: mixed ombrophilous forest(NA), ombrophilous forest with selective Araucariaangustifolia logging (N), A. angustifoliareforestation (A), and reforestation of Pinus elliottii(P). According to an increasing degree of disturbance, the habitats might beordered as follows: (NA)<(N)<(A)<(P). We conducted 24 surveys in eachhabitat over a period of 1 year. Our results indicate that: (1)Terricola diversity is inversely related to the degree of habitat disturbance;(2) there are species (Geoplana franciscana,Geoplana sp. 5, and possibly Geoplanidae 3 andNotogynaphallia guaiana) that prefer habitats located onthe extreme right along the main axis of a detrended correspondence analysisordination and therefore can be considered as indicators of well preserved,natural habitats. On the other hand there are species(Xerapoa sp. 1, Choeradoplanaiheringi, G. marginata sensu Marcus andGeoplana sp. 2) preferring more disturbed habitats, whichmay form biological indicators of such disturbances.  相似文献   

14.
Spatial priorities for the conservation of three key Mediterranean habitats, i.e. seagrass Posidonia oceanica meadows, coralligenous formations, and marine caves, were determined through a systematic planning approach. Available information on the distribution of these habitats across the entire Mediterranean Sea was compiled to produce basin-scale distribution maps. Conservation targets for each habitat type were set according to European Union guidelines. Surrogates were used to estimate the spatial variation of opportunity cost for commercial, non-commercial fishing, and aquaculture. Marxan conservation planning software was used to evaluate the comparative utility of two planning scenarios: (a) a whole-basin scenario, referring to selection of priority areas across the whole Mediterranean Sea, and (b) an ecoregional scenario, in which priority areas were selected within eight predefined ecoregions. Although both scenarios required approximately the same total area to be protected in order to achieve conservation targets, the opportunity cost differed between them. The whole-basin scenario yielded a lower opportunity cost, but the Alboran Sea ecoregion was not represented and priority areas were predominantly located in the Ionian, Aegean, and Adriatic Seas. In comparison, the ecoregional scenario resulted in a higher representation of ecoregions and a more even distribution of priority areas, albeit with a higher opportunity cost. We suggest that planning at the ecoregional level ensures better representativeness of the selected conservation features and adequate protection of species, functional, and genetic diversity across the basin. While there are several initiatives that identify priority areas in the Mediterranean Sea, our approach is novel as it combines three issues: (a) it is based on the distribution of habitats and not species, which was rarely the case in previous efforts, (b) it considers spatial variability of cost throughout this socioeconomically heterogeneous basin, and (c) it adopts ecoregions as the most appropriate level for large-scale planning.  相似文献   

15.
Abstract

Prioritization of endemic, threatened species and the habitats where they live is a crucial point of conservation actions, particularly in areas with rich endemic floras. In this study, we have developed a new procedure to define the conservation priorities among endemic plants and habitats by evaluating eight criteria. Five criteria deal with the geographic and ecological range of the evaluated species, whereas the other three refer to threats. After the evaluation of each criterion, we combined the partial scores to obtain a priority index (PI). Finally, we characterized the EU habitat categories of conservation concern on the basis of the average PI value of the plants living in each habitat. We tested the method on a list of 260 endemic plants from a biodiversity hotspot (Sardinia) that had an average PI of 3.66 ± 0.16. Even if the habitat categories that are most rich in endemic plants were rocky habitats, and coastal/halophytic habitats, the most endangered habitat was coastal sand dunes (PI = 6.75 ± 1.15). The method herein presented is complementary with the application of IUCN criteria. This integrated approach is a concrete solution that adapts IUCN criteria and categories to local contexts.  相似文献   

16.
A consistent vegetation classification is an essential tool for conservation and monitoring purposes, also for semi-natural habitats such as pastures and hay meadows that are linked to traditional land use and generally considered crucial to maintain biodiversity within agricultural systems. Indeed, these habitats can be strongly affected by land abandonment or agriculture intensification. Despite their importance in the framework of the EU Habitats Directive (43/92/EEC), information on distribution, species composition, and conservation status is still lacking for many regions. To fill these gaps, we investigated from a phytosociological point of view the sheep pastures of the North-Western Sardinian trachy-basaltic sector. Three main communities were described as new: (i) perennial montane (meso-supratemperate) cattle and sheep pastures (Loto alpini-Festucetum morisianae); (ii) mixed (annual and perennial) Mediterranean (lower Thermomediterranean to lower supratemperate) sheep pastures (Ornithogalo corsici-Poetum bulbosae); and (iii) annual ploughed subnitrophilous Mediterranean and Temperate pastures (Cynosuro polybracteati-Vulpietum ligusticae). As the first two host numerous endemic taxa and show a peculiar floristic composition, we assign them a higher conservation value, testified also by their classification in two new syntaxa: Danthonio decumbentis-Caricenion insularis (Molinio-Arrhenatheretea) and Ornithogalo corsici-Trifolienion subterranei (Poetea bulbosae), respectively.  相似文献   

17.
In Tunisia, the increasing pharmacological demand for spontaneous capers is actually leading to progressive forest overexploitation and genetic erosion of the species that is actually represented by scattered populations. Therefore, inventories with emphasis on the characterization, management and conservation of this medicinal plant are becoming a great need.In this work, genetic and phylogenetic criteria based on isozyme markers were used for the prioritization of spontaneous Capparis spinosa L. populations for conservation according to Vane-Wright and collaborators taxic method.Enzymatic loci varied in their ability to detect variation and population analyses indicated that most of the variation is partitioned between rather than within populations. Fst, gene flow values, PCA and cluster analysis also revealed significant differentiation between all populations.When combing phylogenetic and genetic criteria we were able to prioritize some of the populations for conservation. Therefore, the standardization and the summatory of all indices indicated that the populations Nebeur, Nahli and Dyr rank as a priority for conservation.So far, results of the present study appear to justify the in situ conservation strategy, where core areas completely free from perturbation would be defined for the populations with the highest priority for conservation, with the populations presenting unique alleles. This would guarantee the maintenance of most of the species’ genetic variation. The ex situ conservation management strategy would imply the setting up of specialized nurseries and national collections that are still missing in the country to counteract population fragmentation, demographic loss and genetic erosion threatening such spontaneous populations.  相似文献   

18.
Multi-facet diversity indices have been increasingly widely used in conservation ecology but congruence analyses both on horizontal and vertical axes have not yet been explored. We investigated the vertical and horizontal distributions of α and β taxonomic (TD), functional (FD) and phylogenetic diversity (PD) in a three-dimensional structured ecosystem. We focused on the Mediterranean coralligenous assemblages which form complex structures both vertically and horizontally, and are considered as the most diverse and threatened communities of the Mediterranean Sea. Although comparable to tropical reef assemblages in terms of richness, biomass and production, coralligenous assemblages are less known and more rarely studied, in particular because of their location in deep waters. Our study covers the entire range of distribution of coralligenous habitats along the French Mediterranean coasts, representing the most complete database so far developed for this important ecosystem. To our knowledge, this is the first analysis of spatial diversity patterns of marine biodiversity on both horizontal and vertical scales.Our study revealed that taxonomic diversity differed from functional and phylogenetic diversity patterns at the station level, the latter two being strongly structured by depth, with shallower stations generally richer than deeper ones. Considering all stations, phylogenetic diversity was less congruent to taxonomic diversity (Pearson's correlation of r = 0.48) but more congruent to functional diversity (r = 0.69) than randomly expected. Similar congruence patterns were revealed for stations deeper than 50 m (r = 0.44 and r = 0.84, respectively) but no significantly different congruence level than randomly expected was revealed among diversity facets for more shallow stations. Mean functional α- and β-diversity were lower than phylogenetic diversity and even lower than taxonomic α- and β-diversity for both vertical and horizontal scales. Low FD and PD values at both α- and β-diversity indicated functional and phylogenetic clustering. Community dissimilarities (β-diversity) increased over depth especially in central and eastern part of the French Mediterranean littoral and in northern Corsica, indicating coralligenous vertical structure within these regions. Overall horizontal β-diversity was higher within the 50–70 m depth belts.We conclude that taxonomic diversity alone is inadequate as a basis for setting conservation goals for this ecosystem and additional information, at least on phylogenetic diversity, is needed to preserve the ecosystem functioning and coralligenous evolutionary history. Our results highlight the necessity of considering different depth belts as a basis for regional scale conservation efforts. Current conservation approaches, such as the existing marine protected areas, are insufficient in preserving coralligenous habitats. The use of multi-facet indices should be considered, focusing on preserving local diversity patterns and compositional dissimilarities, both vertically and horizontally.  相似文献   

19.
In the Mediterranean, habitat-forming corals often characterize essential fish habitats. While their distribution is sufficiently known for the western basin, few data are available from the Central-Eastern Mediterranean Sea (CEM). This study fills this gap supplying the largest dataset ever built on the geographical and bathymetric distribution of the most relevant habitat-forming corals (Eunicella cavolini, Eunicella verrucosa, Eunicella singularis, Leptogorgia sarmentosa, Paramuricea clavata, Corallium rubrum and Savalia savaglia) of the CEM. Information collected from different sources such as literature, citizen science, and from the World Wide Web (WWW) was combined. Videos published on the WWW provided additional information on the presence of fishing lines and signs of damage, as well as on the distribution of purple and yellow-purple colonies of Paramuricea clavata. The study highlighted the impressive amount of information that the WWW can offer to scientists, termed here as Web Ecological Knowledge (WEK). The WEK is constantly fuelled by internauts, representing a free, refreshable, long-term exploitable reservoir of information. A quick and easy method to retrieve data from the WWW was illustrated. In addition, the distribution of corals was overlapped to marine protected areas and to the distribution of environmental conditions suitable for coralligenous habitats, fragile biogenic Mediterranean structures hosting complex assemblages in need of strict protection. The collected data allowed identifying priority areas with high species diversity and sites that are impacted by fishing activities. Supplied data can correctly address conservation and restoration policies in the CEM, adding an important contribution to ecosystem-based marine spatial planning.  相似文献   

20.
Proposed strategies to protect biodiversity within agricultural systems are often based on botanical criteria with plant species richness generally considered the prime indicator of conservation potential. While wet grasslands dominated by rushes (Juncus spp.) are commonly considered to be of lesser ecological value than those which are more botanically diverse (e.g. Carex dominated wet grasslands), their value for invertebrates such as Diptera has not yet been fully explored. Data from two Diptera families (Sciomyzidae and Syrphidae) were examined at spatial, temporal and spatiotemporal scales to determine the contribution of two different (Juncus and Carex dominated) wet grassland habitats towards the maintenance of Diptera diversity. The two habitats were significantly different in terms of community structure for both families and temporal variation was a significant component of dipteran diversity. Spatiotemporal analysis showed that species turnover between habitats at different times made the most significant contribution to overall Diptera diversity. Temporal variation of both families suggests that the relative importance of each habitat type to overall diversity fluctuates depending on sampling period, with both habitats supporting diversity at different times. Our results indicate that lowland wet grasslands characterised by Juncus cover need to be recognised as ecologically important for the maintenance of dipteran diversity. We discuss the possible implications for the diversity of Diptera in wet grasslands if these commonly perceived marginal areas (both agriculturally and ecologically) are ignored in conservation strategies. The necessity of recognising spatiotemporal variation when evaluating habitats using invertebrates as indicators is also discussed.  相似文献   

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