The present study analyzes the results of a biomonitoring campaign, carried out by means of Hypnum cupressiforme Hedw. moss bags around an oil refinery, located in the southwestern part of Sardinia ...island (Italy). This work focuses mainly on the effects of rainfall and distance from the source of contamination on the content of 14 trace elements measured over 16 years. In addition, to point out any increasing or decreasing trends, as well as any peak in presence of airborne pollutants in the area, annual elements’ concentration values are plotted and discussed. Coefficients of variation were also calculated on accumulation values in order to evaluate stability of measurements across the years and to evaluate if similar exposure conditions, i.e., humidity and distance from contamination source, resulted in more uniform accumulation values. In conclusion, (i) the vicinity of the source of contamination as well as rainfall influenced element content in the biomonitor in the case study differently, depending on the considered element and on the exposure condition, (ii) H. cupressiforme moss bags provided relatively stable measurements during the 16-year time frame (observed variations in elements content can be attributed to environmental inputs in the area), (iii) similar conditions of exposure determined less variable accumulation values.
As they represent actual or potential risks to human and environmental safety and health, abandoned mines are a major global problem. The heavy metal-polluted tailings dump of Barraxiutta ...(Domusnovas, southwestern Sardinia, Italy) is home to a metallicolous population of
(Orchidaceae). A reclamation of the abandoned mine area seems to be approaching, and such an intervention may pose a serious risk for the maintenance of the unique orchid population colonizing the mine wastes. In the present work, the seed packet technique was implemented for the first time to observe orchid seed development in mine wastes. This approach allowed us to explore different seed-based conservation options for the metallicolous orchid population and to gain a deeper grasp of population dynamics and ecology. Four different sowing treatments were set up in the tailing dump and in a near unpolluted site (control site). The field phase of the experiment lasted for 10 months, a period in which the experimental seed bank preservation and incipient seed development were observed and statistically approached. Our findings observed no significant seed loss happening during the experiment, demonstrating the suitability of the seed packet technique to also explore seed bank conservation and development in extreme environmental conditions (i.e., polluted mine wastes). This field method will be a useful tool to further explore the more effective translocation and quasi in situ conservation alternatives for the
metallicolous population. Incipient and site-specific seed development (non-mycorrhizal stage) was observed during the experiment. A plant-soil fungus interaction at the seed level was also observed, the nature of which remains to be ascertained in further studies providing a longer duration for the field phases.
The conservation of species listed in the Bern Convention and European Directive 1992/43/EEC (so-called policy species) is mandatory for European Union (EU) countries. We assessed the conservation ...status of Italian policy species, based on the IUCN categories and criteria, to evaluate the effectiveness of existing protection measures at the national level. Among the 203 vascular plants, bryophytes and lichens evaluated, 41.9% are categorized as threatened, and one is already extinct, indicating that the protection measures for policy species are inadequate. Our results for the Italian policy species are consistent with those of an assessment at the EU level. Conservation priorities should be established at both the national and regional scales. An effective conservation strategy is needed, and in situ and ex situ actions focused on threatened species should be promoted.
Cross-taxon analyses can explain patterns of interaction between taxa and their application in conservation studies can drive management actions. In a coastal sand dune system characterized by a high ...human pressure, we explored the co-occurrence patterns between vascular plants and bryophytes, with a focus on how the occurrence of invasive alien species (IAS) can affect those taxa and their relationships. Species congruences were evaluated at the community level considering taxonomic and functional diversities. Predictive co-correspondence analysis (Co-CA) was applied to quantify the strength of vascular plant communities in predicting bryophytes species composition. The relationship between the composition of vascular plants and bryophytes was significant, even if weak. Altitude and percentage of bare soil cover are the environmental variables exerting greater influence on the two taxa. The presence of IAS affects communities in an opposite way: for vascular plants, species richness increases with the presence of invasive alien species; for bryophytes, IAS’s presence has a low but significant negative influence, both on species richness and in terms of functional diversity. Results give elements for future studies on the effect of IAS on the bryophytes colonizing coastal sand dunes.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•No correlations in species richness and composition were found between the groups.•Bryophyte composition was predictive of lichen composition in biancana grasslands.•A unique species composition was ...related to biancana pediments.•Such pediment species could disappear after the decrease of erosion rates.
Cross-taxon congruence, i.e., using certain taxonomic groups as surrogates for others, is receiving growing interest since it may allow decreasing efforts in biodiversity studies. In this work, we investigated the patterns of cross-taxon congruence in species richness and composition between communities of bryophytes, lichens, and vascular plants in different biancana grasslands of a Special Area of Conservation (SAC) of central Italy. We recorded species presence and abundance in 16 plots of 1 × 1 m size and analyzed the data using Procrustes correlation, co-correspondence analysis, and indicator species analysis. We did not highlight any correlation in species richness and composition between the three taxonomic groups. Conversely, the species composition of bryophyte communities was predictive of the species composition of lichen communities. Moreover, lichen richness was negatively correlated with the total cover of vascular plants. Indicator species analysis evidenced the presence of species from the three biotic communities being particularly related, at least at the local scale, to biancana pediments, like the bryophytes Didymodon acutus and Trichostomum crispulum, the lichens Enchylium tenax, Cladonia foliacea, and Psora decipiens, and the vascular plants Brachypodium distachyon, Parapholis strigosa, and Artemisia caerulescens subsp. cretacea. In the biancana pediments, acrocarp mosses, squamulose lichens, therophyte plants and chamaephyte plants coexisted. In spite of the weak cross-taxon congruence between the three taxonomic groups, this study could highlight a locally unique diversity of bryophytes, lichens, and vascular plants related to the extreme environment of biancana pediments, selected by high soil salinity and deposition from the upper eroded slope. Soil erosion and deposition in biancana badlands supports the increase of local multi-taxonomic plant diversity by creating unique ecosystems. Such biodiversity should be considered locally at risk of disappearance, due to the ongoing vanishing of biancana badlands in central Italy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Volatile Organic Compounds (VOCs) are produced by plants to address a variety of physiological and ecological tasks (among others, stress resistance, and pollinator attraction). Genetics is a key ...factor in determining plants’ VOCs content and emission, nevertheless, environment strongly influences VOCs profiles in plants. Orchids are a widespread group of plants that colonize diverse environments and rely on complex and refined pollination mechanisms to reproduce. Orchids VOCs are rarely studied and discussed in relation to growing conditions. In the present study, we compare the volatile profiles of inflorescences of Himantoglossum robertianum (Loisel.) P. Delforge sampled in six ecologically diverse populations on Sardinia Island (Italy). The essential oils obtained by steam distillation were characterized by GC-FID and GC-MS analysis. A total of 79 compounds were detected, belonging to the chemical classes of saturated hydrocarbons, esters, alcohols, ketones, unsaturated hydrocarbons, sesquiterpenes, oxygenated terpenes, terpenes, acids, and aldehydes. Multivariate statistics separated H. robertianum populations based on their chemical profiles. Differences were positively linked to the distance separating populations and reflected climatological features of the sampling sites. Interestingly, our results differed from those available in the literature, pointing out the high variability of VOCs profiles in this food-deceptive orchid.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The biological species concept is founded in the presence of barriers that restrict gene flow, but species delimitation remain a vivid topic in orchids. In sexually deceptive Ophrys, the role of ...postmating barriers has traditionally been thought to be weak and, despite relevant morphological and ethological differences, only low levels of phylogenetic and genetic differentiation have been recorded. In contrast, not many studies have been focused on the relevance of different barriers in closely related species on islands. Using a morphological approach and experimental crosses to evaluate postmating barriers, we here analyse the distinctness of two sardinian endemic sister‐species, Ophrys annae and O. chestermanii, both currently referred to the O. bornmuelleri group. We found that the two endemics differ sustantially in 16 functional morphological traits. We further obtained asymmetric results from manual crosses suggesting that postmating barriers may reinforce the premating barriers. Our results suggest that in closely related species of Ophrys, gene flow is limited also by postmating barriers which contribute significantly to keeping the species reproductively isolated.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
This study provides a first step toward the knowledge of the alien-dominated and co-dominated plant communities present in Italy. The first ever checklist of the alien phytocoenoses described or ...reported in literature for the Italian territory has been compiled, produced by data-mining in national and local thematic literature. The resulting vegetation-type draft-list has been checked in the light of the most recent syntaxonomic documentation and updated with regards to syntaxonomy and nomenclature, with special reference to the frame proposed in the Italian Vegetation Prodrome. The list includes 27 vascular and one bryophyte vegetation classes, hosting 194 low rank alien-dominated
syntaxa
. The different vegetation types detected for each syntaxonomic class and macro-vegetation group, defined by physiognomical and ecological attributes, are discussed.
Biological and ecological investigations of islands are crucial to explain ecosystem functioning. Many studies on island biodiversity are carried out on oceanic islands. In contrast, information on ...continental islands, such as those in the Mediterranean Sea, is very often fragmented in space and time. Here, a synopsis of the Orchidaceae of Sardinia is presented based on literature surveys and recent botanical field studies. Our final list comprises of 64 species and 14 genera: thirteen species and subspecies were recognized as endemic and four new species were recorded for the flora of the island: Anacamptis palustris (Jacq.) R.M. Bateman, Pridgeon & M.W. Chase; Himantoglossum hircinum (L.) Spreng; Orchis italica Poir.; and Platanthera kuenkelei subsp. kuenkelei var. sardoa R.Lorenz, Akhalk., H.Baumann, Cortis, Cogoni & Scrugli. This orchid richness reflects the geological history of the island that was linked to the mainland several times, facing long periods of isolation. We also discuss a critical point-of-view of the biodiversity shortfalls still problematic for insular orchids. Indeed, within the Mediterranean Basin, the greatest amount of endemism occurs mainly on large islands, and, despite a long history of botanical exploration in European countries, many of them are scarcely investigated. This annotated synopsis shows the potential of continental islands to understand trends in ecology and evolution. Further studies are required to complete our knowledge of the orchid diversity on continental islands in order to propose scientific-based conservation programs to preserve these unique taxa.
Analysis of the seed morphology is a widely used approach in ecological and taxonomic studies. In this context, intraspecific variability with respect to seed morphology (size, weight, and density) ...was assessed in two close
Pau. populations sharing the same ecological conditions, except for the soil pollution distinguishing one of them. Larger and heavier seeds were found in plants growing on the heavy metal polluted site, while no differences in seed density were detected between seeds produced by plants growing on the contaminated and the control site. Moreover, seed coats and embryos varying together in their dimensions were described in the control population, while coats varying in their size independently from embryos were described in plants growing on the polluted site. Seeds from the two studied populations significantly differed in several parameters suggesting that intraspecific seed variability occurred in the case study.
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