Monitoring of Air Pollution by Moss Bags around an Oil Refinery: A Critical Evaluation over 16 Years

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

Epipactis tremolsii seed diversity in two close but extremely different populations: Just a case of intraspecific variability?

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 Epipactis tremolsii 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

The role of pollinator attracting scent in the sexually deceptive orchids Ophrys chestermanii, O. normanii and O. tenthredinifera

Sexual deception of male bees is one of the most remarkable mechanisms of pollination (Ackermann 1986, Proctor & al. 1996). Flowers of the orchid genus Ophrys mimic females of their pollinator species, usually bees and wasps, to attract males, which try to copulate with the flowers. During this so-called “pseudocopulation” the male removes the pollinia and transfers them to another flower to ensure pollination. Apart from visual and tactile cues, floral scent was shown to be most important for eliciting mating behaviour in males (Kullenberg 1961, Schiestl & al. 1999, Ayasse & al. 2003). Pollination in Ophrys is highly specific and usually each Ophrys species attracts only one pollinator species (Paulus & Gack 1990). The high degree of specialization provides the means of reproductive isolation between the intercrossable Ophrys-species (Ehrendorfer 1980). The complex odour-bouquets released by the flowers are species-specific and often consist of more than 100 different chemical compounds (Borg-Karlson & al. 1985, Ayasse 2006). Speciation in Ophrys-orchids may be brought about by changes in the pollinator attracting floral scent. The attraction of a new pollinator may act as a pre-zygotic isolation barrier (Stebbins 1970, Paulus & Gack 1990, Soliva & al. 2001). We investigated three sympatrically occuring Ophrys-species on Sardinia. O. chestermanii and O. normanii are endemic and are both pollinated by males of the bumblebee B. vestalis. O. tenthredinifera is pollinated by Eucera nigrilabris. There are different opinions concerning the taxonomic status of O. normanii. It has been described as an actual hybrid between O. chestermanii and O. tenthredinifera (Wood 1983). Paulus & Gack (1995) suggested that it is an own species, that either has developed from a hybrid between O. chestermanii and O. normanii or that has evolved by radiation from O. tenthredinifera. By conducting behavioural-tests with B. vestalis males, performing gas chromatographic analyses and electrophysiological studies we wanted to identify pollinator attracting scent and to clarify the taxonomic status of O. normanii.Sexualtäuschorchideen der Gattung Ophrys (Orchidaceae) imitieren die Weibchen ihrer Bestäuber in Duft, Form und Farbe. Insektenmännchen versuchen mit dem Labellum der Blüte zu kopulieren und transportieren den Pollen von Blüte zu Blüte, wodurch die Orchidee bestäubt wird. In dieser Arbeit untersuchten wir die Bestäuber anlockenden Duftstoffe der beiden endemisch auf Sardinien vorkommenden Arten O. normanii und O. chestermanii, die beide von Bombus vestalis Männchen (Hymenoptera: Apidae) bestäubt werden und von O. tenthredinifera, die Eucera nigrilabris (Hymenoptera: Apidae) zur Bestäubung anlockt. O. normanii wurde von Wood (1983) als Primärhybride beschrieben. Nach Paulus und Gack (1995) handelt es sich um eine hybridogene Art oder um eine Art die durch Abspaltung von O. tenthredinifera entstanden ist. Das Ziel der Untersuchungen war die Identifizierung Männchen-anlockender Verbindungen. Die Attraktivität der drei Arten für B. vestalis Männchen sollte Hinweise auf den Artstatus von O. normanii geben. In Biotests mit B. vestalis-Männchen lösten Blütenextrakte von O. normanii und O. chestermanii ebenso wie B. vestalis-Weibchen Kopulationsverhalten der Männchen aus, nicht jedoch Extrakte von O. tenthredinifera. Folglich handelt es sich bei O. normanii nicht um einen aktuellen Hybriden zwischen O. chestermanii und O. tenthredinifera. Ein Vergleich der GC-EAD-aktiven Duftbouquets mittels Diskriminanzanalyse ergab große Ähnlichkeiten zwischen O. normanii und O. chestermanii für die Substanzklassen der Ester, Alkohole und Fettsäuren, die daher vermutlich eine Schlüsselfunktion bei der Bestäuberanlockung haben

Heavy metal tolerance strategies in metallicolous and non-metallicolous populations of mosses: Insights of γ+β-tocopherol regulatory role

As bryophytes present the capacity to colonize a wide range of habitats, including extreme environments (e.g., mine areas), we first checked the global response of bryophytes to heavy metals (HM) by a systematic review. This analysis found i) the lack of studies in a polluted environment and ii) resulted in a global trend of photochemical efficiency decrease when bryophytes faced heavy metals. Secondly, we characterized the photoprotective responses of four metallicolous populations of mosses (Lewinskya rupestris, Polytrichum commune, Ptychostomum compactum and Rhynchostegium confertum) naturally growing in an abandoned mine area by an experimental field approach. As a result, we found markedly species-specific tolerance patterns: i) less tolerant species, presenting high pollutants content accompanied by marked dissipative and antioxidative strategies. This strategy was depicted by the species R. confertum that result to be a good sentinel species due to the high pollutant content and high physiological sensitivity.; ii) intermediate tolerant species presenting a medium content of pollutants and less marked photoprotective mechanisms, and iii) most tolerant species minimizing pollutants content and consequently presenting no changes in their physiological performance. This evidence support that species’ bryological attributes have a key role in determining species’ tolerance towards environmental heavy metals, and should be taken into consideration in future studies. The findings of this study also pointed out that the higher levels of γ + β-tocopherol in metallicolous populations could play a regulatory role in metal stress tolerance in mosses and it could be a suitable functional responsive trait for environmental response prediction to heavy metals in polluted environments

Volatile Organic Compounds (VOCs) Diversity in the Orchid Himantoglossum robertianum (Loisel.) P. Delforge from Sardinia (Italy)

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

Global and Regional IUCN Red List Assessments: 6

In this contribution, the conservation status assessment of four vascular plants according to IUCN categories and criteria are presented. It includes the assessment of Epipactis maricae (Croce, Bongiorni, De Vivo & Fori) Presser & S.Hertel at global level, and the regional assessment of Cerinthe retorta Sm. (Italy), Platanthera kuenkelei H.Baumann subsp. kuenkelei (Europe) and Typha elephantina Roxb. (Egypt)

Bryophyte flora of some temporary pools in Sardinia and Corsica

A comparative study of the bryophytes in some Sardinian and Corsican wetlands of major naturalistic value, such as the "padule of Suartone" (SE Corsica) and "pauli of the Giara of Gesturi" (C Sardinia), was carried out. In Europe, these habitats ( Mediterranean temporary pond) are indicated as priority natural habitats under the Habitats Directive 92/43/EEC. In the Sardinian pauli, 56 taxa (50 Bryophyta and six Marchantiophyta) were found, while in the Corsican padule, 30 taxa (21 Bryophyta and nine Marchantiophyta) are reported. Among the bryophytes collected in the padule, the discovery of Scleropodium cespitans, Riccia perennis and Campylopus introflexus is of particular phytogeographic interest. Data are here reported together with information on the phytogeography and ecology of the recorded species

A COMPARATIVE STUDY ON FLORAL TRAITS IN TWO MEDITERRANEAN ORCHIDS WITH A DIFFERENT POLLINATION STRATEGIE

The extraordinary diversity of living forms is the direct consequence of the rising of reproductive barriers which interrupt genic flow between populations causing their differentiation and so an independent evolution. Most species of flowering plants offer rewards to their pollinators, but some base their pollination on deception (1). Deception is typical of Orchidaceae and some authors define this strategy as the key element of the diversification of this family (2). Using a morphological and functional approach on eight orchids species as sample of food (3) and sex (4) deception strategies, we predicted that stigmatic cavity and pollinia will covary, since they are both involved at different levels as a pre-zygotic barrier; their relation should be stronger in sexual deceptive orchids than in those that use food deception. We also investigated (i) the variation of each floral part within each species and each deception strategy; (ii) if pollinia and stigmatic cavity are interrelated and finally (iii) if a precise morphology of stigmatic cavity and pollinia is promoted by natural selection. In Sardinia there are 16 endemic species among 68 taxa of orchids, within the subtribe Orchidinae, the genera Anacamptis, Himantoglossum and Orchis are used examples of food deception and Ophrys as an example of sexual deception. We examined 160 flowers over the duration of this study. Means and standard deviations of floral traits were run. Correlations between pollinia length and height and width of stigmatic cavities are performed (Fig. 1). We correlated these values both at species and strategy levels. Positive correlations are generally expressed in both strategies. We found that phylogentically closely related species have pollinia length very similar. Hence, we suggest that this is due to adaptation to the similar morphology of strictly phylogenetically related pollinator or because the studied species can be affected by phylogenetic constraints. The comparative analysis of the various floral traits underlines how the each sterile portion is variable within in each species. This confirms the idea that in deceptive orchids the variation of sterile floral traits can be relevant in the deception process. In contrast, a stabilizing selection is proposed to explain the low variability in fertile traits