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Featured researches published by Cristiana Vieira.


Journal of Bryology | 2012

New national and regional bryophyte records, 31

L. T. Ellis; Antun Alegro; Halina Bednarek-Ochyra; Ryszard Ochyra; A. Bergamini; A Cogoni; P. Erzberger; P Gorski; N. J. M. Gremmen; Helena Hespanhol; Cristiana Vieira; L E Kurbatova; Marc Lebouvier; A Martinčič; A. K. Asthana; R. Gupta; Virendra Nath; Rayna Natcheva; Anna Ganeva; T. Özdemir; N. Batan; Vítězslav Plášek; R D Porley; M Randić; Jakub Sawicki; W. Schröder; Cecília Sérgio; V R Smith; P Sollman; S. Ştefănuţ

New national and regional bryophyte records, 31 L T Ellis, A Alegro, H Bednarek-Ochyra, R Ochyra, A Bergamini, A Cogoni, P Erzberger, P Górski, N Gremmen, H Hespanhol, C Vieira, L E Kurbatova, M Lebouvier, A Martinčič, A K Asthana, R Gupta, V Nath, R Natcheva, A Ganeva, T Özdemir, N Batan, V Plášek, R D Porley, M Randić, J Sawicki, W Schroder, C Sérgio, V R Smith, P Sollman, S Ştefănuţ, C R Stevenson, G M Suárez, B Surina, G Uyar, Z Modrič Surina The Natural History Museum, UK, University of Zagreb, Croatia, Polish Academy of Sciences, Poland, Swiss Federal Research Institute WSL, Switzerland, Università degli Studi di Cagliari, Italy, Berlin, Germany, Poznań University of Life Sciences, Poland, Diever, The Netherlands, Universidade do Porto, Portugal, Russian Academy of Sciences, Russia, Université de Rennes 1, France, 12 Ljubljana, Slovenia, CSIR-National Botanical Research Institute, India, Bulgarian Academy of Sciences, Bulgaria, Karadeniz Technical University, Turkey, University of Ostrava, Czech Republic, Cerca dos Pomares, Portugal, Public Institution, Croatia, University of Warmia and Mazury in Olsztyn, Poland, Ludwigsstadt, Germany, Universidade de Lisboa, Portugal, University of Stellenbosch, South Africa, St Anna Parochie, The Netherlands, Institute of Biology Bucharest of Romanian Academy, Romania, Norfolk, UK, Facultad de Ciencias Naturales, Argentina, University of Primorska, Slovenia, Zonguldak Karaelmas University, Turkey, Natural History Museum Rijeka, CroatiaDetermination of development priority of information system subsystems is a problem that warrants resolution during information system development. It has been proven, previously, that this problem of information system development order is in fact NP-complete, NP-hard, and APX-hard. To solve this problem on a general case we have previously developed Monte-Carlo randomized algorithm, calculated complexity of this algorithm, and so on. After previous research we were able to come into possession of digraphs that represent real-world information systems. Therefore, in this paper we will empirically analyze Monte-Carlo algorithm to determine how the algorithm works on real-world examples. Also, we will critically review the results and give some possible areas of future research as well.


Journal of Bryology | 2006

New national and regional bryophyte records, 13

T. L. Blockeel; H. Bednarek-Ochyra; Ryszard Ochyra; Petra Hájková; Michal Hájek; J. Kuĉera; Kürschner; Frank Müller; G. Olivá; Gerald Parolly; R D Porley; Susana Rams; Ana Séneca; Cecília Sérgio; C. C. Townsend; O. Tyshchenko; Cristiana Vieira

New national and regional bryophyte records, including new data from Bulgaria gathered during GAAV project.


Molecular Phylogenetics and Evolution | 2012

Morphology informed by phylogeny reveals unexpected patterns of species differentiation in the aquatic moss Rhynchostegium riparioides s.l.

Virginie Hutsemekers; Cristiana Vieira; Rosa M. Ros; Sanna Huttunen; Alain Vanderpoorten

Bryophyte floras typically exhibit extremely low levels of endemism. The interpretation, that this might reflect taxonomic shortcomings, is tested here for the Macaronesian flora, using the moss species complex of Rhynchostegium riparioides as a model. The deep polyphyly of R. riparioides across its distribution range reveals active differentiation that better corresponds to geographic than morphological differences. Morphometric analyses are, in fact, blurred by a size gradient that accounts for 80% of the variation observed among gametophytic traits. The lack of endemic diversification observed in R. riparioides in Macaronesia weakens the idea that the low rates of endemism observed in the Macaronesian bryophyte flora might solely be explained by taxonomic shortcomings. To the reverse, the striking polyphyly of North American and European lineages of R. riparioides suggests that the similarity between the floras of these continents has been over-emphasized. Discriminant analyses point to the existence of morphological discontinuities among the lineages resolved by the molecular phylogeny. The global rate of error associated to species identification based on morphology (0.23) indicates, however, that intergradation of shape and size characters among species in the group challenges their identification.


Journal of Bryology | 2004

New national and regional bryophyte records, 10

T. L. Blockeel; H. Bednarek-Ochyra; Ryszard Ochyra; M.A. Bruggeman-Nannenga; N. J. M. Gremmen; J.-P. Hébrard; Leena Luís; Howard W. Matcham; B.J. Oshea; Ana Séneca; Cecília Sérgio; Manuela Sim-Sim; S. Stefaut; Cristiana Vieira

The morphology of Anthoceros erectus Kash. and some other species. Journal of the Indian Botanical Society 39: 568–594. Bharadwaj DC. 1965. Studies in Indian Anthocerotaceae (VI). Some aspects of morphology of Phaeoceros Prosk. Phytomorphology 15: 139–150. Bharadwaj DC. 1981. Taxonomy of Anthocerotales. In Bharadwaj DC, ed. Recent advances in cryptogamic botany. Lucknow: Palaeobotanical Society, 132– 151. Stephani F. 1923. Species Hepaticarum 6. Geneva, 425.


Ecotoxicology and Environmental Safety | 2016

Ecological impact and recovery of a Mediterranean river after receiving the effluent from a textile dyeing industry

Nicole Colin; Alberto Maceda-Veiga; Núria Flor-Arnau; Josep Mora; Pau Fortuño; Cristiana Vieira; Narcís Prat; Jaume Cambra; Adolfo de Sostoa

The textile industry is one of the largest sectors globally, representing up to 20% of industrial water pollution. However, there is limited insight into how fluvial ecosystems respond and recover from this impact. From summer 2012 to spring 2013, we examined water quality and ecological status upstream and 1.5km downstream the input of a textile industry wastewater treatment plant (WWTP) in Ripoll River, NE Spain. The ecological status was determined via diversity measures and 10 biotic indices based on diatoms, macrophytes, macroinvertebrates and fish. Our results showed that the WWTP severely deteriorated water quality and biological communities at the discharge site, but that they improved at 1.5km downstream. Severity also varied across taxa and seasons, being fish the most affected taxa and spring the season with the best ecological status. The strong correlation amongst water quality variables and many biotic indices across taxa indicated that this is a chronic pollution event affecting multiple trophic levels. Thus, this study suggests that there is an urgent need to invest in wastewater treatment in this industry to preserve the ecological integrity of Ripoll River and especially its fish fauna. Likewise, it illustrates the diagnostic power of biotic indices based on diatoms, macroinvertebrates and fish, as driven by the European Water Framework Directive.


Hydrobiologia | 2014

The relevance of bryophytes in the macrophyte-based reference conditions in Portuguese rivers

Cristiana Vieira; Francisca C. Aguiar; Maria Teresa Ferreira

The identification of macrophyte reference communities represents a significant challenge in Mediterranean zones, where few aquatic taxa exist compared to other regions of the world. In the highly seasonal rivers of Portugal, we explored the contribution of bryophytes to enhance the compositional and ecological characterization of reference conditions. We performed partitioning, classification, and ordination analyses and obtained eight groups of bryophytic assemblages explained by water availability and quality. Groups A, B, and H assemblages are type-specific of the inland areas of the northern eco-region, reflecting the neutral minerotrophic currents with summer low currents. Groups C and D are type-specific of acidic oligotrophic shifting currents dependent of precipitation events in the mountainous streams of the North Atlantic eco-region. Groups E, F, and G are widespread in continental northern, central, and southern zones in neutral and highly mineralized watercourses with seasonal dryness. We propose bryophytes as a tool in the characterization of the reference conditions for two main reasons: (i) many of the recorded taxa are capable of withstanding the natural seasonal desiccation, and (ii) the type-specific bryophytes have perennial life-strategies and can be assessed at any time of year as a support for other type-specific macrophytes in compositional assessments of reference conditions.


Cryptogamie Bryologie | 2012

Floristic and ecological survey of bryophytes from Portuguese watercourses

Cristiana Vieira; Ana Séneca; Cecília Sérgio

Abstract — A floristic and ecological survey was carried out in 187 watercourses of the Portuguese Northwest mainland and Sicó mountain regions located in the transition zone between Atlantic and Mediterranean territories. This work mainly focused on the update of the bryophyte taxa along fluvial and geologic gradients, mostly of headwater areas. Seven ecological aspects (type of river segment, micro-habitat, immersion level and water velocity, depth range, shade, lithology and altitude) were classified and used to describe taxa autoecology. This survey is the first to present a comprehensive floristic catalogue and information on Portuguese aquatic and semi-aquatic taxa distribution. A list of 140 bryophytes was established for the studied areas, with predominance of mosses (102 taxa of mosses, 37 taxa of liverworts and 1 taxon of hornworts). Racomitrium aciculare, Platyhypnidium lusitanicum, Hyocomium armoricum, Scapania undulata and Fissidens polyphyllus were the most common taxa and Brachytheciaceae, Grimmiaceae and Fissidentaceae were the most frequent families in the studied micro-habitats. We updated the regional distribution of 30% of the taxa to new provinces of the Portugal. Four mosses and three liverworts are European endemisms, and Racomitrium (R. hespericum and R. lusitanicum) are, Iberian endemics. Distribution maps for selected species (Atlantic, dominant or rare species) are also presented.


Hydrobiologia | 2018

Bryophyte communities of Mediterranean Europe: a first approach to model their potential distribution in highly seasonal rivers

Cristiana Vieira; Francisca C. Aguiar; Ana Portela; Juliana Monteiro; P.J. Raven; N.T.H. Holmes; Jaume Cambra; Núria Flor-Arnau; C. Chauvin; S. Loriot; T. Feret; G. Dörflinger; Mateja Germ; Urška Kuhar; Eva Papastergiadou; P. Manolaki; Maria Rita Minciardi; Antoni Munné; Gorazd Urbanič; Maria Teresa Ferreira

Abstract Mediterranean watercourses are among the most threatened ecosystems worldwide, being increasingly important to understand environmental drivers of biotic assemblages. Our aim was to provide a comprehensive picture of bryophyte communities in Mediterranean rivers and to determine the environmental factors that influence their distribution. We used floristic data collected for inter-calibration purposes under the European Water Framework Directive and River Habitat Survey, from 474 river reaches in six countries of the European Mediterranean basin. We analysed data through classification, ordination and environmental niche modelling techniques, and classified taxa according to biogeographic and aquatic habitat frameworks developed specifically for bryophytes. These analyses revealed four types of communities influenced by spatio-temporal precipitation patterns, altitude and water chemistry factors, most notably calcium and manganese. Community types are compositionally differentiated, although they share some core taxa and show an overall tendency to have several temperate and exclusively aquatic taxa despite the intermittent nature of water flow in highly seasonal Mediterranean rivers. The modelling approach can be improved at a more local scale when more bryological data and higher-resolution environmental information become available. Given future scenarios of climate change and human alteration of hydrological regimes, broader scales studies are needed to monitor shifts in bryophyte communities.


Journal of Bryology | 2011

Conocephalum salebrosum Szweykowski, Buczkowska & Odrzykoski (Marchantiopsida): modelling the occurrence of a hygrophytic species new to the bryoflora of Portugal, Madeira and Azores

Cecília Sérgio; Cristiana Vieira; D Claro; C. Garcia

Abstract Conocephalum salebrosum Szweykowski, Buczkowska & Odrzykoski, a hygrophytic species, is newly reported for several localities in continental Portugal as well as in Madeira and Azores Islands. Information from studied specimens, and a map showing the actual distribution of this species and its closely related species, C. conicum (L.) Dumort., are provided as the basis for a discussion on the chorology and ecological ranges of both species. Additionally, a model of the potential distribution for both species in continental territory is developed through the Maximum Entropy Modelling technique, followed by an explanation of an hypothesis on the preferences of each species of Conocephalum known in this territory.


Systematics and Biodiversity | 2010

Molecular, phytochemical and morphological characterization of the liverwort genus Radula in Portugal (mainland, Madeira, Azores)

Michael Stech; Manuela Sim-Sim; M. Glória Esquível; Leena Luís; Susana Fontinha; Carlos Lobo; C. Garcia; Soraia Martins; Cristiana Vieira; José G. Barroso; Luis G. Pedro; A. Cristina Figueiredo

Relationships of the eight species of the liverwort genus Radula occurring in Portugal (mainland, the Madeira and Azores archipelagos), including the Macaronesian endemics R. jonesii and R. wichurae, were evaluated based on molecular, phytochemical and morphological–anatomical data. Maximum parsimony and Bayesian analyses were performed with sequences from three plastid DNA markers (trnS GGA-rps4 spacer, rps4 gene, trnL UAA intron), volatile oil compounds, as well as qualitative morphological–anatomical characters. In addition, the molecular data were subjected to maximum likelihood analysis. The eight taxa, R. aquilegia, R. carringtonii, R. complanata, R. holtii, R. jonesii, R. lindenbergiana, R. nudicaulis and R. wichurae, can be clearly distinguished from each other, either by molecular data alone or by combination of characters from all three data sets. Radula aquilegia is monophyletic according to the molecular data, but shows considerable, yet undescribed intraspecific morphological and phytochemical variability. Recognition of R. complanata and R. lindenbergiana as separate species, previously based solely on the paroecious vs. dioecious sexual condition, is moderately supported by the molecular phylogenetic analyses and strongly supported by the phytochemical data. The Radula species, narrowly distributed in Macaronesia and Atlantic Europe, probably have two different origins. For Radula holtii and R. nudicaulis, connections with Radula species from the Neotropics are indicated. The other species, among them the two Macaronesian endemics, are closely related with the R. complanata/R. lindenbergiana complex, which is widely distributed in the northern hemisphere.

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Maria Teresa Ferreira

Instituto Superior de Agronomia

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Sarah Stow

Natural History Museum

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Francisca C. Aguiar

Instituto Superior de Agronomia

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Jaume Cambra

University of Barcelona

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