141 resultados para Botanists.


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Se aportan nuevos datos sobre el origen y el alcance de las falsificaciones detectadas en los exsiccata de E.M. Reineck, que contaminan importantes herbarios. Igualmente se alerta sobre otras colecciones y publicaciones poco fiables, que hay que poner, al menos, en cuarentena.

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Descendiente de Antoni Bolòs i Ferrussola-farmacéutico botánico que herborizó en varias comarcas catalanas y mantuvo contactos con otros botánicos de su época, especialmente con su suegro Joan Minuart i Parets- y de Francesc Bolòs i Germà-farmacéutico naturalista, autor de trabajos de flora y de geología-, sobrino-nieto de Estanislau Vayreda i Vila, nieto de Ramon de Bolòs i Saderra-los dos últimos, farmacéuticos botánicos, miembros de la escuela de Antoni C. Costa- e hijo de Antoni de Bolòs i Vayreda-farmacéutico botánico, director del Institut Botànic de Barcelona en tiempos difíciles-, Oriol de Bolòs i Capdevila (Olot, 16 de marzo de 1924- Barcelona, 22 de marzo de 2007) siguió-de un modo que podríamos considerar natural, lógico- la tradición científica de su familia de estudio de las plantas, siendo el primero de la saga en ejercerla no a partir de los estudios de farmacia, sino desde los de ciencias naturales....

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The Bernades herbarium in the Botanic Institute of Barcelona (BC).- The BC-Bernades herbarium is one of the oldest collections conserved in the Botanical Institute of Barcelona. It contains part of the field collections of Miquel Bernades i Mainader and Miquel Bernades i Clarís, doctors of medicine and botanists of Catalonian origin living in Madrid in the 18th century. The collection consists of 817 sheets, the complete list provided in the annexe. We also present information concerning the localities of certain specifi c recollections, the taxonomic groups and families, as well as a list of sheets of special interest. This list contains witness of cornfi eld weed now very rare or extinct in Iberian lands, such as Hymenocarpos circinatus (L.) Savi or Securigera securidaca (L.) Degen & Dörfl , and also some of the first witness known from Spain of introduced plants, such as Aster cordifolius L. or Bidens bipinnata L.

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Creu Casas i Sicart, Professor Emeritus at the Autonomous University of Barcelona, Catalonia, and a member of the Insti­tute of Catalan Studies (IEC) since 1978, died at the advanced yet still active age of 94 in Bellaterra on 20 May 2007, after a brief illness. She was unquestionably the most prominent bota­nist in the field of bryological research (mosses, liverworts, and hornworts) covering the entire Iberian Peninsula and Balearic Islands in the past 50 years. She also served as the president (1980-1982) of one of the most prestigious affiliates of our in­ stitute, the Catalan Institution of Natural History

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Alors qu'il travaillait les lichens dans son laboratoire, chez lui à Nancy, le Professeur Werner s'écroula, victime d'une attaque cérébrale. Hospitalisé, il mourait quatre semaines après, le 28 mars 1977. Son travail, consacré surtout à la cryptogamie, et notamment à la recherche lichénologique, l'avait donc accompagné jusqu'à la fin de sa vie.

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Santiago Llensa nasqué a Hostalric (la Selva) el dia 9 de novembre de 1911. Era fili d'una familia arrelada a la comarca. Per part de la seva mare tenia però parents i interessos a Prada (el Confient), cosa que contribuí a fer que sempre mantingués uns certs lligams amb la cultura francesa.

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Amb el traspàs del germà Malagarriga ha desaparegut un deis ultims testimonis directes d'aliò que era la Botànica catalana durant el primer terç del segle vinte, abans de la guerra, i, en particular, el darrer component del grup de botànics que es constituí sota el mestratge de frère Sennen.

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Antoni de Bolòs, un home modest i de bona voluntat, hagué de dur el timó de l'Institut Botànic de Barcelona, la institució cabdal de la Botànica catalana, durant anys molt dificils. Ho feu dignament, evita el col-lapse de l'Institut i deixà ais seus successors un Institut Botànic que mante els trets essencials de centre d'alta recerca científica que l'havien caracteritzat des de la seva fundació.

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El 23 de juny de 1973 el veli amie Sventenius fou aixafat per un auto en sortir del Jardi Botànic de Las Palmas, on treballava. Sota la impressió de la seva inesperada mort em venen a la memòria una colla de records personáis que voldria deixar escrits.

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This article discusses briefly the evolution of fire in the Mediterranean biome and reviews afterwards the main research themes that geographers, ecologists and botanists have developed around forest fires issues in the Mediterranean

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Cyclamen colchicum has a mixed history in the hands of botanists. This paper examines the genetic identity of a group of wild Cyclamen populations from the Caucasus to discover whther they are Cyclamen colchicum, C. purpurascens or a mixture of the two. The collections supplemented by material collected at the type locality for C. colchicum, proved to be a single but variable genetic group of C. colchicum that was distinct from C. purpurascens.

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A presença cada vez mais disseminada de organismos exóticos (muitos dos quais se tornam invasores) nas diferentes regiões do planeta levou ao surgimento de uma linha de pesquisa na ecologia voltada às invasões biológicas. E para permitir a comunicação entre autores também foi desenvolvido um arcabouço terminológico. Mas, apesar disso, a terminologia relativa às bioinvasões tem sido ignorada por boa parte dos botânicos no Brasil. Há uma boa dose de confusão entre botânicos sobre o que seja uma espécie exótica, naturalizada, invasora, daninha e ruderal, levando ao uso inconsistente da terminologia. Além disso, diferentes autores têm adotado posturas praticamente opostas ao lidar com espécies exóticas em suas áreas de estudo, seja na preparação de tratamentos taxonômicos, seja na publicação de levantamentos florísticos e fitossociológicos. Enquanto alguns pesquisadores incluem em floras mesmo espécies cultivadas que não se reproduzem, outros excluem plantas invasoras comuns e conspícuas. Nós apresentamos aqui, em português, os principais conceitos relativos ao tema da bioinvasão e chamamos a atenção dos autores brasileiros para a necessidade de utilizar de modo consistente o arcabouço terminológico já existente na literatura. Também propomos a adoção de rótulos claros para informar quais espécies são exóticas na área estudada, diferenciando-as das nativas, e sugerimos critérios para ajudar botânicos a decidirem quando uma planta exótica deve ou não ser incluída em tratamentos taxonômicos ou levantamentos de florística.

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Loss of small herbaria is an unfortunate global trend, and initiation of new collections at small academic institutions is an increasingly rare occurrence. In 2006, a new herbarium was established at the State University of New York College at Plattsburgh. The PLAT herbarium has since grown to more than 7,000 specimens, many of them representative of the flora of northeastern New York (especially Clinton County). Previous to 2006, this region was without a recognized herbarium, the nearest in-state collections being more than 150 miles away. Although botanists have previously worked in the region, relatively few plant species were recorded for Clinton County by the New York Flora Atlas – a resource providing species distribution records based on specimens accessioned in herbarium collections. Given the dearth of available distribution data for Clinton County (including the eastern Adirondack Mountains and the western Lake Champlain valley), this project sought to provide records of previously unreported species by comparing NY Flora Atlas maps with current holdings. 203 species will now be added to the NY Flora Atlas for Clinton County, roughly half of those considered exotic. This exercise has amplified the importance of supporting and maintaining small regional herbaria as repositories of valuable biodiversity information. Likewise, this project also highlights the enduring value of training in floristics and taxonomy.

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A new species of dioecious Solanum from the Australian “Dioicum Complex” of Solanum subgenus Leptostemonum is described. Solanum cowiei Martine sp. nov., is allied with other members of this problematic lineage, but differs in its slender leaves, limited armature and diminutive habit. The species was first segregated by botanists at the Northern Territory Herbarium as Solanum sp. Litchfield (I.D. Cowie 1428); and specimens representing this species have also been referred to by Symon as Solanum sp. Fitzmaurice River. Collections suggest that this is an endemic of the sub-arid tropical zone of the Northern Territory. SEM images support initial assumptions that the new species is cryptically dioecious via production of inaperturate pollen grains in morphologically hermaphrodite flowers.

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Whether interspecific hybridization is important as a mechanism that generates biological diversity is a matter of controversy. Whereas some authors focus on the potential of hybridization as a source of genetic variation, functional novelty and new species, others argue against any important role, because reduced fitness would typically render hybrids an evolutionary dead end. By drawing on recent developments in the genetics and ecology of hybridization and on principles of ecological speciation theory, I develop a concept that reconciles these views and adds a new twist to this debate. Because hybridization is common when populations invade new environments and potentially elevates rates of response to selection, it predisposes colonizing populations to rapid adaptive diversification under disruptive or divergent selection. I discuss predictions and suggest tests of this hybrid swarm theory of adaptive radiation and review published molecular phylogenies of adaptive radiations in light of the theory. Some of the confusion about the role of hybridization in evolutionary diversification stems from the contradiction between a perceived necessity for cessation of gene flow to enable adaptive population differentiation on the one hand [1], and the potential of hybridization for generating adaptive variation, functional novelty and new species 2, 3 and 4 on the other. Much progress in the genetics 5, 6, 7, 8 and 9 and ecology of hybridization 9, 10 and 11, and in our understanding of the role of ecology in speciation (see Glossary) 12, 13 and 14 make a re-evaluation timely. Whereas botanists traditionally stressed the diversity-generating potential of hybridization 2, 3 and 14, zoologists traditionally saw it as a process that limits diversification [1] and refer to it mainly in the contexts of hybrid zones (Box 1) and reinforcement of reproductive isolation [15]. Judging by the wide distribution of allopolyploidy among plants, many plant species might be of direct hybrid origin or descended from a hybrid species in the recent past [16]. The ability to reproduce asexually might explain why allopolyploid hybrid species are more common in plants than in animals. Allopolyploidy arises when meiotic mismatch of parental chromosomes or karyotypes causes hybrid sterility. Mitotic error, duplicating the karyotype, can restore an asexually maintained hybrid line to fertility. Although bisexual allopolyploid hybrid species are not uncommon in fish [17] and frogs [18], the difficulty with which allopolyploid animals reproduce, typically requiring gynogenesis[19], makes establishment and survival of allopolyploid animal species difficult.