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1.
Plants (Basel) ; 12(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37836139

RESUMO

High-mountain and arctic plants are considered especially sensitive to climate change because of their close adaptation to the cold environment. Kalmia procumbens, a typical arctic-alpine species, reaches southernmost European localities in the Pyrenees and Carpathians. The aim of this study was the assessment and comparison of the current potential niche areas of K. procumbens in the Pyrenees and Carpathians and their possible reduction due to climate change, depending on the scenario. The realized niches of K. procumbens in the Pyrenees are compact, while those in the Carpathians are dispersed. In both mountain chains, the species occurs in the alpine and subalpine vegetation belts, going down to elevations of about 1500-1600 m, while the most elevated localities in the Pyrenees are at ca. 3000 m, about 500 m higher than those in the Carpathians. The localities of K. procumbens in the Carpathians have a more continental climate than those in the Pyrenees, with lower precipitation and temperatures but higher seasonality of temperature and precipitation. The species covered a larger area of geographic range during the Last Glacial Maximum, but its geographic range was reduced during the mid-Holocene. Due to climate warming, a reduction in the potential area of occurrence could be expected in 2100; this reduction is expected to be strong in the Carpathians and moderate in the Pyrenees.

2.
Ecol Evol ; 11(10): 5075-5095, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34025993

RESUMO

AIM: The aim of this study is to model the past, current, and future distribution of J. phoenicea s.s., J. turbinata, and J. canariensis, based on bioclimatic variables using a maximum entropy model (Maxent) in the Mediterranean and Macaronesian regions. LOCATION: Mediterranean and Macaronesian. TAXON: Cupressaceae, Juniperus. METHODS: Data on the occurrence of the J. phoenicea complex were obtained from the Global Biodiversity Information Facility (GBIF.org), the literature, herbaria, and the authors' field notes. Bioclimatic variables were obtained from the WorldClim database and Paleoclim. The climate data related to species localities were used for predictions of niches by implementation of Maxent, and the model was evaluated with ENMeval. RESULTS: The potential niches of Juniperus phoenicea during the Last Interglacial period (LIG), Last Glacial Maximum climate (LGM), and Mid-Holocene (MH) covered 30%, 10%, and almost 100%, respectively, of the current potential niche. Climate warming may reduce potential niches by 30% in RCP2.6 and by 90% in RCP8.5. The potential niches of Juniperus turbinata had a broad circum-Mediterranean and Canarian distribution during the LIG and the MH; its distribution extended during the LGM when it was found in more areas than at present. The predicted warming in scenarios RCP2.6 and RCP8.5 could reduce the current potential niche by 30% and 50%, respectively. The model did not find suitable niches for J. canariensis during the LIG and the LGM, but during the MH its potential niche was 30% larger than at present. The climate warming scenario RCP2.6 indicates a reduction in the potential niche by 30%, while RCP8.5 so indicates a reduction of almost 60%. MAIN CONCLUSIONS: This research can provide information for increasing the protection of the juniper forest and for counteracting the phenomenon of local extinctions caused by anthropic pressure and climate changes.

3.
Sci Rep ; 10(1): 4810, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32179791

RESUMO

Juniperus thurifera is a key element of the forest communities in arid and semi-arid areas of the western Mediterranean. Previous genetic and morphological investigations suggested that Algerian populations are genetically more similar to European than to Moroccan populations and advocated their recognition at the variety rank. We aimed to investigate the spatial genetic structure in J. thurifera to verify the distinct character of the Algerian population in terms of the genetic breaks reported among several North African taxa. We also modelled species distributions since the Eemian to recognise the impact of past climatic changes on the current pattern of diversity and predict possible changes in species distribution in the future. Species-specific microsatellites were used in the analysis of 11 populations from Algeria, Morocco and Europe. We revealed the significant genetic distinctiveness of the Algerian populations from the Moroccan and European stands that may have important taxonomic and conservation implications. The diversity pattern revealed for J. thurifera reflects the east-west genetic splits reported among some North African plant and animal taxa and suggests an impact of shared historical processes. Additionally, modelling of the distribution allowed us to identify possible glacial refugia and their impact on the modern pattern of differentiation in J. thurifera. Reduction of species occurrence, especially in the European domain, is likely according to the future projections of the species distribution.


Assuntos
Variação Genética , Juniperus/genética , África do Norte , Argélia , Repetições de Microssatélites , Marrocos , Especificidade da Espécie
4.
AoB Plants ; 2012: pls013, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22822421

RESUMO

BACKGROUND AND AIMS: Juniperus excelsa M.-Bieb. is a major forest element in the mountains of the eastern part of Mediterranean and sub-Mediterranean regions. This study comprises the first morphological investigation covering a large part of the geographical range of J. excelsa and aims to verify the congruency between the morphological results and molecular results of a previous study. METHODOLOGY: We studied 14 populations sampled from Greece, Cyprus, Ukraine, Turkey and Lebanon, 11 of which have previously been investigated using molecular markers. Three hundred and ninety-four individuals of J. excelsa were examined using nine biometric features characterizing cones, seeds and shoots, and eight derived ratios. Statistical analyses were conducted in order to evaluate the intra- and inter-population morphological variability. PRINCIPAL RESULTS: The level of intra-population variability observed did not show any geographical trends. The total variation mostly depended on the ratios of cone diameter/seed width and seed width/seed length. The discrimination analysis, the Ward agglomeration method and barrier analysis results showed a separation of the sampled populations into three main clusters. These results confirmed, in part, the geographical differentiation revealed by molecular markers with a lower level of differentiation and a less clear geographical pattern. The most differentiated populations using both markers corresponded to old, isolated populations in the high altitudes of Lebanon (>2000 m). Moreover, a separation of the northern Turkish population from the southern Turkish populations was observed using both markers. CONCLUSIONS: Morphological variation together with genetic and biogeographic studies make an effective tool for detecting relict plant populations and also populations subjected to more intensive selection.

5.
Acta colomb. psicol ; 11(2): 47-53, dic. 2008. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-635111

RESUMO

Se analizó la formación de clases de estímulos equivalentes vía reglas verbales mediante la utilización de un procedimiento de igualación de la muestra en un formato de "papel y lápiz" para el entrenamiento y evaluación de discriminaciones condicionales. Participaron voluntariamente 36 estudiantes universitarios; el grupo experimental recibió entrenamiento de línea base vía reglas verbales, pruebas de mantenimiento de línea base y pruebas de equivalencia; el grupo control sólo recibió las pruebas. El instrumento desarrollado mostró ser efectivo. Un número considerable de participantes del grupo experimental logró formar dos clases de estímulos equivalentes, a diferencia del grupo control en que ninguno de los participantes formó las clases. El desarrollo de procedimientos efectivos con "papel y lápiz" y reglas, podría apoyar la enseñanza de habilidades básicas de lectura en poblaciones grandes con economía de tiempo y dinero.


Equivalent class formation through verbal rules was analyzed. A matching-to-sample procedure for training and probing of conditional discriminations in a "paper and pencil" format was used. Participants were 36 voluntary students, divided in two groups. The baseline training for the experimental group was carried out via verbal rules. This group also received maintenance probes and equivalence probes during the baseline period. The control group was only given the probes. The instrument used proved to be effective. The majority of participants in the experimental group formed two equivalent classes, unlike the control group in which none of the participants showed class formation. The development of effective procedures using "paper and pencil" and verbal rules format, could support the teaching of basic reading skills in large populations with a resulting economy of time and money.


Neste artigo foi analisada a formação de classes de estímulos equivalentes via regras verbais, recorrendo a um procedimento de igualação da amostra em um formato de "papel e lápis" para o trenamento e avaliação de discriminações condicionais. Participaram 36 estudantes voluntários. O grupo experimental foi treinado em linha de base via regras verbais, provas de manutenção de linha de base e provas de equivalência. O grupo controle só recebeu as provas. O instrumento desenvolvido foi efetivo. Um número considerável de participantes do grupo experimental formou duas classes de estímulos equivalentes. No grupo controle ninguém dos participantes formou as classes. O desenvolvimento de procedimentos efetivos com "papel e lápis" e regras poderia ajudar no ensino de habilidades básicas de leitura nas populações grandes, economizando tempo e dinheiro.


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Universidades , Aprendizagem Verbal , Equivalência Terapêutica , Tamanho da Amostra , Discriminação Psicológica
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