Past and present potential distribution of the Iberian Abies species: a phytogeographic approach using fossil pollen data and species distribution models

Abstract

24Aim Quaternary palaeopalynological records collected throughout the Iberian Peninsula and 25 species distribution models (SDMs) were integrated to gain a better understanding of the 26 historical biogeography of the Iberian Abies species (i.e. Abies pinsapo and Abies alba). We 27 hypothesize that SDMs and Abies palaeorecords are closely correlated, assuming a certain 28 stasis in climatic and topographic ecological niche dimensions. In addition, the modelling 29 results were used to assign the fossil records to A. alba or A. pinsapo, to identify environmental 30 variables affecting their distribution, and to evaluate the ecological segregation between the 31 two taxa. propose that the two taxa remained isolated throughout the Quaternary, indicating a significant 44 geographical and ecological segregation. In addition, no significant differences were detected 45 comparing the three projections (present-day, Mid-Holocene and LGM), suggesting a relative 46 climate stasis in the refuge areas during the Quaternary. 47 Main conclusions Our results confirm that SDM projections can provide a useful complement 48to palaeoecological studies, offering a less subjective and spatially explicit hypothesis 49 concerning past geographic patterns of Iberian Abies species. The integration of ecological-50 niche characteristics from known occurrences of Abies species in conjunction with 51 palaeoecological studies could constitute a suitable tool to define appropriate areas in which to 52 focus proactive conservation strategies. 53 54

Modelación de nichos ecológicos basado en tres escenarios de cambio climático para cinco especies de plantas en zonas altas de Costa Rica

“…Este programa funciona con algoritmos que predicen el potencial de distribución de las especies en relación con las condiciones ambientales conocidas y recopiladas a través del tiempo (Phillips et al, 2006) y se considera como uno de los programas más eficientes en dichas predicciones (Elith et al, 2006). Se calibró con las siguientes especificaciones para todos los casos: con los puntos reportados de colecta en visitas de campo y herbarios, el 75% de las ocurrencias para el entrenamiento del modelo y el 25% restante para realizar su respectiva validación, según sugieren varios autores (Alba-Sánchez et al, 2010). Además, se configuró con un umbral de convergencia de 0,00001 y como límite superior de corrida un valor de 10000 interacciones según recomienda Phillips et al (2006).…”

Regeneration of Abies pinsapo within gaps created by Heterobasidion annosum-induced tree mortality in southern Spain

“…is a relict fir species endemic to southern Spain and northern Morocco. It has been hypothesized that A. pinsapo populations remained isolated throughout the Quaternary (Alba- Sánchez et al 2010). Such historical isolation caused significant morphological, genetic and ecological differentiation from other circum-Mediterranean fir species (Martín et al 2010, Linares 2011.…”

Reducción de la incertidumbre de los modelos de distribución de especies con datos ecológicos y paleoecológicos.

“…En los últimos años se ha incrementado el número de estudios que incorporan información paleobotánica en los modelos proyectados al pasado que demuestran el gran potencial que tiene la combinación de los MDE con estos datos (p.e. Alba-Sánchez et al, 2010y Maiorano et al, 2013.…”

“…Salix herbacea L. in Alsos et al, 2009), although for fossil pollen assemblages (Table 2.1), local presence/absence of a species is defined using a species-specific threshold value in the pollen percentage (Alba-Sánchez et al, 2010). The same pollen threshold can be used for all the species in the study (Maiorano et al, 2013), or more than one threshold per species can be used to assess the sensitivity of the analysis to the threshold .…”

“…In most of the studies, the thresholds are specified and referenced, although they may be different for the same species (e.g. 0.01% and 0.02% for Abies alba and Picea abies in ; 1% for Abies in Alba-Sánchez et al (2010); 1% for Abies alba, Picea abies and Fagus sylvatica in Maiorano et al (2013); 0.5% and 1% for Fagus in ). Certain SDM studies have attempted to reduce the uncertainty of the threshold selection by using abundance pollen data (e.g.…”