Browsing by Author "Sancho, Gisela"

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    Disentangling morphologically similar species of the Andean forest: integrating results from multivariate morphometric analyses, niche modelling and climatic space comparison in Kaunia (Eupatorieae: Asteraceae)
    (2018) Viera Barreto, Jessica N.; Pliscoff, Patricio; Donato, Mariano; Sancho, Gisela
    Six subtropical montane forest Kaunia spp. are remarkable for their superficial morphological similarity. We aim to explore different sources of data to clarify species delimitation in this complex of Kaunia. Morphological variation and environmental data of the species of the complex were assessed by using multivariate morphometric analyses. We performed a species distribution modelling approach applying BIOMOD2. Morphological quantitative traits allowed discrimination of some species in the complex. These Kaunia spp. have statistically different potential distributions, although some similarities between species in terms of climatic space were found. The species with the most similar climatic space were K. saltensis and K. lasiophthalma. The biogeographical context that could have affected the distribution of these two species is discussed. The results of our integrative study confirm the discrimination of three species, K. lasiophthalma, K. rufescens and K. saltensis, but the other three, K. arbuscularis, K. longipetiolata and K. uber, are here regarded as a single entity.
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    Modeling the 20th-century distribution changes of Microgyne trifurcata, a rare plant of the southern South American grasslands
    (SPRINGER, 2021) Viera Barreto, Jessica Noelia; Sancho, Gisela; Mauricio Bonifacino, Jose; Pliscoff, Patricio
    Microgyne trifurcata is a rare native plant species from one of the areas with the highest human impact on the environment in southern South America. Its habitat, mostly grasslands suitable for agriculture, has been increasingly covered by crops since the late 1800s. Microgyne trifurcata provides an excellent case study to understand how different environmental variables have affected the distribution area of a rare species. This study aims to estimate the impact of topoclimatic and land-use changes in the distribution of Microgyne trifurcata throughout the twentieth century. We carried out recent past and present distribution modeling using the Ensembles of Small Models (ESM) methodology. In this spatio-temporal study, we included climatic, topographic, and land-use variables. We classified the occurrences into two periods of the twentieth century. The first dates from 1901 to 1940, and the second, from 1960 to 2000, when the main cropping changes of the area occurred. The projected area between 1960 and 2000 provides for this species new suitable habitats toward the northeast of the area of study. Our results highlight the importance of assessing the combined impacts of climate and land-use changes on species distributions over time. This study shows that the potential area of Microgyne trifurcata decreased and underwent fragmentation throughout the twentieth century when these variables combined are used to model its distribution. Our outcomes prompt future studies on the vulnerability of Microgyne trifurcata to outline conservation strategies.
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    Phylogenetic relationships and generic reassessment of Proustia andallies (Compositae: Nassauvieae)
    (2018) Sancho, Gisela; Katinas, Liliana; Viera Barreto, Jessica N.; Moreira Muñoz, Andrés; Luebert, Federico