Person:
Sánchez Jiménez, Abel

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First Name
Abel
Last Name
Sánchez Jiménez
URI
https://hdl.handle.net/20.500.14352/74359
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Biológicas
Department
Biodiversidad, Ecología y Evolución
Area
Matemática Aplicada
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UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet IDGoogle Scholar ID

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2017 - 20193
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Start date: 2001 × Subject: 574 ×

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Now showing 1 - 3 of 3
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    Influencia de la temperatura sobre la asimetría de pilancones en ambiente granítico. Aplicación de un modelo de regresión lineal
    (Boletín de la Sociedad Geológica Mexicana, 2017) García Rodríguez, Manuel; Sánchez Jiménez, Abel; Murciano Cespedosa, Antonio; Pérez Uz, María Blanca; Martín Cereceda, María Mercedes
    Las pilas representan un tipo de forma presente en casi todos los ambientes climáticos. El trabajo estudia el papel de los ciclos térmicos como un agente importante del modelado y asimetría que presentan las paredes de las pilas en un clima Mediterrá- neo templado - frío. El estudio se ha realizado en el macizo granítico de la Pedriza de Manzanares, zona protegida de gran valor ambiental, incluida en el Parque Nacional de la Sierra de Guadarrama (Madrid, España). El análisis de la variabilidad térmica mediante modelos de regresión perió- dica múltiple, pone de manifiesto la influencia de los ciclos diario y anual en función de las orientaciones norte y sur de las paredes de las pilas. Un modelo matemático de regresión lineal muestra cómo la variabilidad térmica diaria influye en la alteración de las paredes de las pilas, generando superficies planas o de concavidad más o menos pronunciada. El trabajo también establece relaciones entre el grado de alteración de las diferentes partes de las pilas, con la presencia de líquenes y dureza relativa de la roca. Los resultados avalan la hipótesis de relación causal entre la variabilidad térmica y alteración de las paredes de las pilas según su orientación norte o sur.
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    Rain-Fed Granite Rock Basins Accumulate a High Diversity of Dormant Microbial Eukaryotes
    (Microbial Ecology, 2019) Velasco González, Ismael; Sánchez Jiménez, Abel; Singer, David; Murciano Cespedosa, Antonio; Díez-Hermano, Sergio; Lara, Enrique; Martín-Cereceda, Mercedes
    Rain fed granite rock basins are ancient geological landforms of worldwide distribution and structural simplicity. They support habitats that can switch quickly from terrestrial to aquatic along the year. Diversity of animals and plants, and the connexion between communities in different basins have been widely explored in these habitats, but hardly any research has been carried out on microorganisms. The aim of this study is to provide the first insights on the diversity of eukaryotic microbial communities from these environments. Due to the ephemeral nature of these aquatic environments, we predict that the granitic basins should host a high proportion of dormant microeukaryotes. Based on an environmental DNA diversity survey, we reveal diverse communities with representatives of all major eukaryotic taxonomic supergroups, mainly composed of a diverse pool of low abundance OTUs. Basin communities were very distinctive, with alpha and beta diversity patterns non-related to basin size or spatial distance respectively. Dissimilarity between basins was mainly characterised by turnover of OTUs. The strong microbial eukaryotic heterogeneity observed among the basins may be explained by a complex combination of deterministic factors (diverging environment in the basins), spatial constraints, and randomness including founder effects. Most interestingly, communities contain organisms that cannot coexist at the same time because of incompatible metabolic requirements, thus suggesting the existence of a pool of dormant organisms whose activity varies along with the changing environment. These organisms accumulate in the pools, which turns granitic rock into high biodiversity microbial islands whose conservation and study deserve further attention.
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    Germination fitness of two temperate epiphytic ferns shifts under increasing temperatures and forest fragmentation
    (PLoS ONE, 2018) Gabriel Y Galán Moris, José María; Murciano Cespedosa, Antonio; Sirvent, Laure; Sánchez Jiménez, Abel; Watkins, James E.
    Ferns are an important component of ecosystems around the world. Studies of the impacts that global changes may have on ferns are scarce, yet emerging studies indicate that some species may be particularly sensitive to climate change. The lack of research in this subject is much more aggravated in the case of epiphytes, and especially those that live under temperate climates. A mathematical model was developed for two temperate epiphytic ferns in order to predict potential impacts on spore germination kinetics, in response to different scenarios of global change, coming from increasing temperature and forest fragmentation. Our results show that an increasing temperature will have a negative impact over the populations of these temperate epiphytic ferns. Under unfragmented forests the germination percentage was comparatively less influenced than in fragmented patches. This study highlight that, in the long term, populations of the studied epiphytic temperate ferns may decline due to climate change. Overall, epiphytic fern communities will suffer changes in diversity, richness and dominance. Our study draws attention to the role of ferns in epiphytic communities of temperate forests, emphasizing the importance of considering these plants in any conservation strategy, specifically forest conservation. From a methodological point of view, the model we propose could be easily used to dynamically monitor the status of ecosystems, allowing the quick prediction of possible future scenarios, which is a crucial issue in biodiversity conservation decision-making.