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Hirtshals, Denmark

Pecchioni E.,University of Florence | Santo A.P.,University of Florence | Piccini L.,University of Florence | Di Fazio L.,Botanic Garden | And 4 more authors.
Sustainability (Switzerland)

The Vie Cave are a suggestive network of roads deeply entrenched in the rock, dating back to the Etruscan civilization; these ancient roads connect various settlements and necropolises existing mainly in the area of Sovana, Sorano and Pitigliano towns (Southern Tuscany, Italy). The Vie Cave are located in a peculiar geomorphological site, characterized by the presence of extensive pyroclastic deposits, which have been incised by a parallel network of deep gorges. In this paper, the geomorphological, geological and lithological setting of the Vie Cave area, where several Etruscan archaeological sites are found, are described. The precarious stability of the Vie Cave walls and the several archaeological structures carved into them, the high grade of decay shown by the constituent materials, together with the dense vegetation that has developed over the rocky scarps, are taken into account with the aim to provide a complete assessment of the conditions in which the site lies. Finally, we propose some targeted actions related to the preservation of this territory, showing so distinctive morphology, in order to protect the area from further decay to which it would be subjected if it remained abandoned. © 2015 by the authors. Source

Nana E.D.,Charles University | Nana E.D.,International Research and Training Center | Sedlacek O.,Charles University | Bayly N.,SELVA Investigacion Para la Conservacion en El Neotropico | And 6 more authors.
Biodiversity and Conservation

The Cameroon volcanic line montane forests host specific avian assemblages with many endemic species. Such unique bird assemblages deserve adequate description for proper protection. For this purpose, we sampled birds in the upper montane forests of Mts Cameroon and Oku situated at ~2,250 m. We combined point counts and continuous observations to describe species composition and estimate densities of particular species. In total, we recorded 106 species; 45 only on Mt Oku, 21 only on Mt Cameroon, and 40 common to both mountains. The higher species richness on Mt Oku was due to non-forest species that invade the forest interior due to recent human disturbance. Endemic species of the Cameroon volcanic line and montane non-endemic species had higher abundances than widespread species in general. As a result, we did not find a positive abundance-range-size relationship for both locations. Our findings support a previously made observation that montane species of the Cameroon volcanic line have higher densities compared to widespread species. However, we also show that the structures of avian assemblages vary between sites as species spatial turnover was lower on Mt Cameroon than on Mt Oku and species common to both were more abundant on Mt Cameroon. This could be attributed to the more pristine forest on Mt Cameroon, with higher annual rainfall but also due to lower human impact and the existence of a continuous forest. Conservation action within the broader landscape context is thus necessary to secure diverse montane forests in West-Central Africa in the future. © 2014 Springer Science+Business Media Dordrecht. Source

Wojtal A.Z.,Polish Academy of Sciences | Ognjanova-Rumenova N.,Bulgarian Academy of Science | Buczko K.,Hungarian Natural History Museum | Siwek J.,Jagiellonian University | And 2 more authors.

Navicula striolata was originally described as N. digitoradiata var. striolata from modern material collected in Sweden. After examination of a sample collected from Belgium, the variety was transferred to N. reinhardtii as N. reinhardti var. gracilior. From this time a large mix up of these and related taxa was observed in the literature. A similar species, Navicula rumaniensis had also been established in 1934 from Neogene Romanian materials but there has been much confusion regarding the status of these taxa, leading to a poor understanding of their distribution. In this study, type material of Navicula digitoradiata var. striolata, N. reinhardtii var. gracilior and N. rumaniensis are revised using light and scanning electron microscopy in order to clarify their identity and to investigate possible conspecificity. The results indicate that these species are not synonyms. Conspecificity of the modern N. digitoradiata var. striolata and N. reinhardti var. gracilior was confirmed and lectotypes of both varieties have been designated whereas N. rumaniensis proved to be a separate species. In addition, the study of Neogene material from Bulgaria revealed the presence of a new Navicula taxon—N. friedelhinziae. The morphology of these and similar taxa is discussed. © 2015 Magnolia Press. Source

Wetzel C.E.,Luxembourg Institute of Science and Technology | Ector L.,Luxembourg Institute of Science and Technology | Van De Vijver B.,Botanic Garden | Van De Vijver B.,University of Antwerp | And 3 more authors.

The identity and nomenclatural history of several small-celled naviculoid taxa are revisited. The species discussed here are important from the ecological point of view since they are often dominant in benthic freshwater communities. The original concepts of several species that have suffered major taxonomic drift due to their entangled nomenclatural history are discussed, and forgotten epithets are resurrected. We examined the original material of Navicula aggerica E. Reichardt, Navicula atomoides Grunow, N. crassulexigua E. Reichardt, N. minima Grunow, N. minima var. typica R. Ross, N. minutissima (Kütz.) Grunow, N. saugerresii Desm. N. seminulum Grunow, N. seminulum var. intermedia Hust. N. seminulum var. radiosa Hust. N. stroemii Hust. N. subbacillum Hust. N. subseminulum Hust. N. tantula Hust. N. vasta Hust. N. ventraloides Hust. Stauroneis fonticola Hust. and Synedra minutissima Kütz. Several of these names were regarded as synonyms in many floristic works and, as such, remained forgotten or ignored. Analyses using light and scanning electron microscopy indicate conspecificity of Navicula minima (= Sellaphora seminulum sensu auct. nonnull.) with Sellaphora saugerresii (Desm.) C.E. Wetzel et D.G. Mann comb. nov. which has priority against N. minima. Synedra minutissima is lectotypified and transferred to Halamphora minutissima (Kütz.) C.E. Wetzel et Compère comb. nov. Navicula minutissima (Kütz.) Grunow 1860, nom. illeg. and Navicula minima Grunow pro parte, typo excl. designate one and the same species (valid and legitimate), currently known as Sellaphora aggerica (E. Reichardt) Falasco et Ector. We consider Sellaphora atomoides (Grunow) C.E. Wetzel et Van de Vijver comb. nov. (= Eolimna tantula sensu auct. nonnull.) and Sellaphora nigri (De Not.) C.E. Wetzel et Ector comb. nov. (= Eolimna minima sensu auct. nonnull.) to be separate species, although morphologically very similar. Sellaphora crassulexigua (E. Reichardt) C.E. Wetzel et Ector comb. nov. and Sellaphora subseminulum (Hust.) C.E. Wetzel comb. nov. are rarely encountered, but usually found in calcareous springs and aerial habitats, respectively. All species are transferred to the genus Sellaphora on the basis of their valve morphology, pending molecular studies confirming the monophyly of the group once living material of each can be located and brought into clonal culture. Additionally, 64 established taxa from Navicula s.l. Eolimna or Naviculadicta are formally transferred to Sellaphora. Navicula subminuscula Manguin is formally transferred to the genus Craticula Grunow. © Czech Phycological Society (2015). Source

Jager A.K.,Copenhagen University | Stafford G.I.,Botanic Garden
South African Journal of Botany

Tulbaghia species are used in traditional medicine in southern Africa. They contain sulphur compounds, which have anti-Candida activity. The sulphur compounds are unstable, so different extraction methods were investigated. Grinding the rhizome material in liquid nitrogen and extraction with ethanol yielded the best results. Eight Tulbaghia species were tested and found to contain the same pattern of sulphur compounds on the TLC plate, though in varying concentrations, except T. simmleri, for which sulphur compounds could not be detected. This means that more species can potentially be utilised for the drug Tulbaghiae rhizoma. A simple quantitative TLC dilution method was developed, which can be used to ascertain whether the rhizome material contains a sufficient level of sulphur compounds. The effect of storage was investigated. The content of sulphur compounds in the rhizomes decreased fast upon storage, half of the main compound was lost four weeks after harvest. Possible adulterants for Tulbaghiae rhizoma are Allium sativum and Agapanthus campanulatus. It was not possible to detect adulteration with A. sativum, but a simple TLC test could detect adulteration with 10 % A. campanulatus material. © 2012 South African Association of Botanists. Published by Elsevier B.V. Source

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