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Past and present potential distribution of the Iberian Abies species: A phytogeographic approach using pollen data and species distribution models
This is the accepted version of the following article: Alba-Sánchez, F., López-Sáez, J. A., Pando, B. B.-d., Linares, J. C., Nieto-Lugilde, D. and López-Merino, L. (2010), Past and present potential distribution of the Iberian Abies species: a phytogeographic approach using fossil pollen data and species distribution models. Diversity and Distributions, 16: 214–228, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/j.1472-4642.2010.00636.x/abstract.Aim - Quaternary palaeopalynological records collected throughout the Iberian Peninsula and species distribution models (SDMs) were integrated to gain a better understanding of the historical biogeography of the Iberian Abies species (i.e. Abies pinsapo and Abies alba). We hypothesize that SDMs and Abies palaeorecords are closely correlated, assuming a certain stasis in climatic and topographic ecological niche dimensions. In addition, the modelling results were used to assign the fossil records to A. alba or A. pinsapo, to identify environmental variables affecting their distribution, and to evaluate the ecological segregation between the two taxa.
Location - The Iberian Peninsula.
Methods - For the estimation of past Abies distributions, a hindcasting process was used. Abies pinsapo and A. alba were modelled individually, first calibrating the model for their current distributions in relation to the present climate, and then projecting it into the past—the last glacial maximum (LGM) and the Middle Holocene periods—in relation to palaeoclimate simulations. The resulting models were compared with Iberian-wide fossil pollen records to detect areas of overlap.
Results - The overlap observed between past Abies refugia—inferred from fossil pollen records—and the SDMs helped to construct the Quaternary distribution of the Iberian Abies species. SDMs yielded two well-differentiated potential distributions: A. pinsapo throughout the Baetic mountain Range and A. alba along the Pyrenees and Cantabrian Range. These results propose that the two taxa remained isolated throughout the Quaternary, indicating a significant geographical and ecological segregation. In addition, no significant differences were detected comparing the three projections (present-day, Mid-Holocene and LGM), suggesting a relative climate stasis in the refuge areas during the Quaternary.
Main conclusions - Our results confirm that SDM projections can provide a useful complement to palaeoecological studies, offering a less subjective and spatially explicit hypothesis concerning past geographic patterns of Iberian Abies species. The integration of ecological-niche characteristics from known occurrences of Abies species in conjunction with palaeoecological studies could constitute a suitable tool to define appropriate areas in which to focus proactive conservation strategies.The Andalusian Innovation,
Science, and Industry Regional Ministry and the National Plan of the Spanish Government
Espectro polínico de la franja litoral en la provincia de Granada: periodo estudiado 2003-2005
XV lnternational A.P.L.E. Symposium of Palynolog
Estudio de la actividad alergénica de Olea europaea L. y su relación con ingresos de pacientes en los Servicios de Urgencias (Hospital San Cecilio de Granada)
XV lnternational A.P.L.E. Symposium of Palynolog
Análisis aerobiológico del polen de Cupressaceae en Granada (sureste P. Ibérica): su repercusión en la población atópica
XV lnternational A.P.L.E. Symposium of Palynolog
Didactic resources for the localization and identification of mosses and liverworts in the city of Cordoba
Este proyecto trata de utilizar la ciudad de Córdoba como recurso educativo para la enseñanza del mundo vegetal, en concreto musgos y hepáticas. Se trata de acercar al alumnado estos organismos, que aunque pasan desapercibidos por su pequeño tamaño, están presentes en las ciudades. El objetivo ha sido diseñar rutas que se puedan realizar con alumnado en las que sea frecuente encontrar especies de briofitos y aportarles material para realizar de forma autónoma la identificación de las especies. Se han desarrollado itinerarios por la ciudad de Córdoba y por el Campus Universitario de Rabanales en los que se han añadido con una señal las especies que se pueden encontrar en cada uno de los puntos marcados a lo largo de la ruta, para que el alumnado pueda encontrar las especies sin dificultad. Se ha elaborado también una guía didáctica que incluye una pequeña introducción de los briofitos, una clave dicotómica para la identificación de las especies, utilizado caracteres morfológicos fácilmente observables a simple vista y una guía fotográfica con fotos y descripciones detalladas de las especies de hepáticas y musgos que se han encontrado con frecuencia en la ciudad. El material se ha elaborado en español y en inglés.This project tries to use the city of Córdoba as educational resource for teaching plant biology, specifically mosses and liverworts. The aim is to bring these organisms closer to the students since, although they go unnoticed due to their small size, they are present in cities. The objectives have been to design routes to be done with students where it is common to find bryophytes and to provide students with material so they can carry out the identification in an autonomous way. A series of itineraries have been developed in the city of Córdoba and in the University Campus of Rabanales. The species that can be found in each of the marked point along the route have been marked with a label so that the students can find the species without difficulty and at the same time a didactic guide has been elaborated including a small introduction of bryophytes, a dichotomous key for identification of the species using morphological characters observable to the naked eye and a photographic guide with photos and detailed descriptions of the liver and moss species that have been found frequently in the city of Córdoba. This material has been prepared in Spanish and English
Unraveling the forcings controlling the vegetation and climate of the best orbital analogues for the present interglacial in SW Europe
The suitability of MIS 11c and MIS 19c as analogues of our present interglacial and its natural evolution is still debated. Here we examine the regional expression of the Holocene and its orbital analogues over SW Iberia using a model-data comparison approach. Regional tree fraction and climate based on snapshot and transient experiments using the LOVECLIM model are evaluated against the terrestrial-marine profiles from Site U1385 documenting the regional vegetation and climatic changes. The pollen-based reconstructions show a larger forest optimum during the Holocene compared to MIS 11c and MIS 19c, putting into question their analogy in SW Europe. Pollen-based and model results indicate reduced MIS 11c forest cover compared to the Holocene primarily driven by lower winter precipitation, which is critical for Mediterranean forest development. Decreased precipitation was possibly induced by the amplified MIS 11c latitudinal insolation and temperature gradient that shifted the westerlies northwards. In contrast, the reconstructed lower forest optimum at MIS 19c is not reproduced by the simulations probably due to the lack of Eurasian ice sheets and its related feedbacks in the model. Transient experiments with time-varying insolation and CO2 reveal that the SW Iberian forest dynamics over the interglacials are mostly coupled to changes in winter precipitation mainly controlled by precession, CO2 playing a negligible role. Model simulations reproduce the observed persistent vegetation changes at millennial time scales in SW Iberia and the strong forest reductions marking the end of the interglacial "optimum".SFRH/BD/9079/2012, SFRH/BPD/108712/2015, SFRH/BPD/108600/2015info:eu-repo/semantics/publishedVersio
Spatially explicit assessment of genetic variation to inform conservation effort for an endangered Mediterranean conifer, Cedrus atlantica
Preserving the genetic diversity of forest species is critical for maintaining their adaptive potential and allowing for generation turnover in forest ecosystems. Considering an uncertain future, it is necessary to establish reliable genetic conservation strategies to optimize the genetic variation preserved within populations in a spatially explicit context to assist decision-makers. Hence, we aimed to incorporate genetic information into spatially designed conservation actions. Cedrus atlantica is a large, long-lived conifer native to the mountains of North Africa, threatened by extinction. The relevant genetic units for conservation were selected using Bayesian analysis. The relative contribution of the populations to the genetic pool that maximized the species' genetic diversity was calculated to design an optimal seed bank. Finally, the relationship between the genetic composition and bioclimatic variables was estimated and projected throughout the study area under current and future climatic conditions. Three relevant genetic units were found for C. atlantica conservation that maximizes genetic diversity in a spatial context. Bioclimatic variables with the highest influence on genetic composition were closely related to climate warming and decreased soil water availability. We identified the role of genetic markers in designing a reliable conservation strategy for forest trees considering climate change, increased deforestation, and aridity. Projections of genetic composition due to the climate in the study region of North Africa provide spatially explicit guidance for optimizing the selection and preservation of seed banks
Are rates of thermal niche evolution in cave beetles enough to cope with climate change?
Póster presentada en la conferencia Adapting to Global Change in the Mediterranean hotspot (AGCM), celebrada en Sevilla del 18 al 20 de septiembre de 2013.Climate change has become one of the main threats to global biodiversity. However, the extent to which species are threatened by climate change depends on how they respond to these new climatic conditions. They can disperse to more suitable locations, or they can cope through phenotypic plasticity and, ultimately, via evolutionary adaptation. Most of the studies of the evolutionary and biogeographical consequences of climatic change have been done with terrestrial, mainly vertebrate species. These models present some important uncertainties, as depending on the use of different microhabitats at different times within the same area the species can be exposed to a range of temperature or humidity sometimes much wider than the change predicted by the most pessimistic scenarios of climate change. The possibility of range movement tracking suitable habitats is also a confounding factor when trying to infer the conditions at which these species were subjected in the past. Here we present a system in which most of these uncertainties do not apply: the deep subterranean environment. The temperature of a cave is highly constant through the year and can be estimated from the mean annual temperature of the surface, and the humidity is always near to the saturation point. These conditions are homogeneous through all possible microhabitats within a cave system, and constant through the year. Most highly specialized cave species have also extremely narrow geographical ranges, which allows to trace their geographical movements through several cladogenetic processes. We focused on a well defined clade of troglobitic beetles of the tribe Leptodirini (Coleoptera, Leiodidae) living in the North-eastern Iberian Peninsula (from the Pyrenees to the coast of Catalonia), including ca. 140 taxa. Most of them are narrow endemic species with a well known distribution. We aim to estimate the rate of thermal niche evolution using two approaches: i) we first reconstructed a minimum rate of evolutionary change from a time calibrated phylogeny using only the current thermal niche of the species; and ii) we then introduced the constraint of the paleotemperatures of the areas occupied by these species during the Pleistocene glacial periods. We finally compare these rates with predicted rates of climate change from 2000 to 2100 for the same areas.Peer Reviewe
Impact of model complexity on cross-temporal transferability in Maxent species distribution models: An assessment using paleobotanical data
Maximum entropy modeling (Maxent) is a widely used algorithm for predicting species distributions across space and time. Properly assessing the uncertainty in such predictions is non-trivial and requires validation with independent datasets. Notably, model complexity (number of model parameters) remains a major concern in relation to overfitting and, hence, transferability of Maxent models. An emerging approach is to validate the cross-temporal transferability of model predictions using paleoecological data. In this study, we assess the effect of model complexity on the performance of Maxent projections across time using two European plant species (Alnus giutinosa (L.) Gaertn. and Corylus avellana L) with an extensive late Quaternary fossil record in Spain as a study case. We fit 110 models with different levels of complexity under present time and tested model performance using AUC (area under the receiver operating characteristic curve) and AlCc (corrected Akaike Information Criterion) through the standard procedure of randomly partitioning current occurrence data. We then compared these results to an independent validation by projecting the models to mid-Holocene (6000 years before present) climatic conditions in Spain to assess their ability to predict fossil pollen presence-absence and abundance. We find that calibrating Maxent models with default settings result in the generation of overly complex models. While model performance increased with model complexity when predicting current distributions, it was higher with intermediate complexity when predicting mid-Holocene distributions. Hence, models of intermediate complexity resulted in the best trade-off to predict species distributions across time. Reliable temporal model transferability is especially relevant for forecasting species distributions under future climate change. Consequently, species-specific model tuning should be used to find the best modeling settings to control for complexity, notably with paleoecological data to independently validate model projections. For cross-temporal projections of species distributions for which paleoecological data is not available, models of intermediate complexity should be selected