Effects of Incubation Temperature on Seed Germination of Mediterranean Plants with Different Geographical Distribution Ranges

Little is known about consequences of the increasing global temperatures on seed germination and even less about the seed germination response of species with different geographical distribution ranges. In the present work, the effect of incubation temperature on seed germination of 31 species from the Iberian Peninsula is analyzed in relation to their geographical distribution range. We tested whether plants with different geographical distribution ranges (Iberian Peninsula endemics, Mediterranean, widely distributed species), respond similarly to incubation temperature using cross-species analysis as well as taking into account phylogenetic relationships among species. Seeds were incubated at 10°C, 15°C, 20°C and 25°C for 6?weeks in darkness. Distribution range appeared as a determinant of germination response to the temperature treatment independent of phylogeny. Widely distributed species were less sensitive than endemic or Mediterranean species to incubation temperatures, which may represent an advantage to colonize new areas or to tolerate changes in the environment. Although their ability to avoid germination during the warm and dry season might be favorable for endemic species in some situations, our results also suggest that under a future of temperature increase imposed by climate change, endemic plant species may be more vulnerable than widely distributed species.     

Predictive modelling of tree species distributions on the Iberian Peninsula during the Last Glacial Maximum and Mid-Holocene

This paper reports a bioclimatic envelope model study of the potential distribution of 19 tree species in the Iberian Peninsula during the Last Glacial Maximum (LGM; 21 000 yr BP) and the Mid-Holocene (6000 yr BP). Current patterns of tree species richness and distributions are believed to have been strongly influenced by the climate during these periods. The modelling employed novel machine learning techniques, and its accuracy was evaluated using a threshold-independent method. Two atmospheric general circulation models, UGAMP and ECHAM3 (generated by the Palaeoclimate Modelling Intercomparison Project, PMIP), were used to provide climate scenarios under which the distributions of the 19 tree species were modelled. The results obtained for these scenarios were assessed by agreement measure analysis; they differed significantly for the LGM, but were more similar for the Mid-Holocene.
The results for the LGM support the inferred importance of pines in the Iberian Peninsula at this time, and the presence of evergreen Quercus in the south. Important differences in the altitude at which the modelled species grew were also predicted. During the LGM, some normally higher mountain species potentially became re-established in the foothills of the Pyrenees. The warm Mid-Holocene climate is clearly reflected in the predicted expansion of broad-leaved forests during this period, including the colonization of the northern part of the Iberian Peninsula by evergreen Quercus species.     

Climatic niche and neutral genetic diversity of the six Iberian pine species: a retrospective and prospective view

Quaternary climatic fluctuations have left contrasting historical footprints on the neutral genetic diversity patterns of existing populations of different tree species. We should expect the demography, and consequently the neutral genetic structure, of taxa less tolerant to particular climatic extremes to be more sensitive to long‐term climate fluctuations. We explore this hypothesis here by sampling all six pine species found in the Iberian Peninsula (2464 individuals, 105 populations), using a common set of chloroplast microsatellite markers, and by looking at the association between neutral genetic diversity and species‐specific climatic requirements. We found large variation in neutral genetic diversity and structure among Iberian pines, with cold‐enduring mountain species (Pinus uncinata, P. sylvestris and P. nigra) showing substantially greater diversity than thermophilous taxa (P. pinea and P. halepensis). Within species, we observed a significant positive correlation between population genetic diversity and summer precipitation for some of the mountain pines. The observed pattern is consistent with the hypotheses that: (i) more thermophilous species have been subjected to stronger demographic fluctuations in the past, as a consequence of their maladaptation to recurrent glacial cold stages; and (ii) altitudinal migrations have allowed the maintenance of large effective population sizes and genetic variation in cold‐tolerant species, especially in more humid regions. In the light of these results and hypotheses, we discuss some potential genetic consequences of impending climate change.     

Effects of temperature and rainfall variation on population structure and sexual dimorphism across the geographical range of a dioecious species

The effects of climate (precipitation and temperature) on sexual dimorphism and population structure were analysed along a broad-scale environmental gradient covering the distributional range of the endemic dioecious species Corema album, along the west coast of the Iberian Peninsula. We aimed to assess distribution constraints and sex-related differences in demography and size associated with higher reproductive investment in females. Nine populations were chosen from across the geographic range of C. album and ten 10 × 10 m plots were established (10 m apart) along a 200-m transect. All male, female and non-reproductive shrubs were quantified within each plot and plant size, photosynthetic layer, height, sex ratio, population density and structure, and spatial segregation of sexes, under environmental conditions ranging from temperate to Mediterranean climate, were recorded and analysed. Increased aridity was related to lower population density and less structured populations, indicating an effect of higher temperature and lower precipitation on regeneration. Sexual dimorphism was influenced by climate, with size differences between sexes varying with aridity. However, demographic differences between sexes reflected in sex ratio deviations or the occurrence of spatial segregation were unrelated to any climatic variable, suggesting the existence of compensatory mechanisms that may counterbalance the higher reproductive effort of female plants. The results show the vulnerability of this endemic species to the increase in aridity expected in the southernmost limit of the biogeographical area due to global climate change, and demonstrate the importance of broad scale studies in the assessment of sexual dimorphism.     

Environmental factors affect the response of microbial extracellular enzyme activity in soils when determined as a function of water availability and temperature

Microorganisms govern soil carbon cycling with critical effects at local and global scales. The activity of microbial extracellular enzymes is generally the limiting step for soil organic matter mineralization. Nevertheless, the influence of soil characteristics and climate parameters on microbial extracellular enzyme activity (EEA) performance at different water availabilities and temperatures remains to be detailed. Different soils from the Iberian Peninsula presenting distinctive climatic scenarios were sampled for these analyses. Results showed that microbial EEA in the mesophilic temperature range presents optimal rates under wet conditions (high water availability) while activity at the thermophilic temperature range (60°C) could present maximum EEA rates under dry conditions if the soil is frequently exposed to high temperatures. Optimum water availability conditions for maximum soil microbial EEA were influenced mainly by soil texture. Soil properties and climatic parameters are major environmental components ruling soil water availability and temperature which were decisive factors regulating soil microbial EEA. This study contributes decisively to the understanding of environmental factors on the microbial EEA in soils, specifically on the decisive influence of water availability and temperature on EEA. Unlike previous belief, optimum EEA in high temperature exposed soil upper layers can occur at low water availability (i.e., dryness) and high temperatures. This study shows the potential for a significant response by soil microbial EEA under conditions of high temperature and dryness due to a progressive environmental warming which will influence organic carbon decomposition at local and global scenarios.     

Arboreal and prostrate conifers coexisting in Mediterranean high mountains differ in their climatic responses

In contrast to most high elevation areas, plant growth at Mediterranean mountains is exposed to a summer drought period, which represents an additional climatic constraint to low temperatures. Although arboreal and shrubby conifers coexist at high altitudes, most dendroecological studies have focused on climatic responses of tree species, whereas those of shrubby species remain mostly unexplored. We built tree-ring width chronologies for two conifer species, a shrub (Juniperus sabina) and a tree (Pinus sylvestris), coexisting at three high-altitude localities of the Iberian System mountains, eastern Spain. We analyzed their climate–growth relationships for the period 1950–2009 using correlation analyses and multiple regressions. Coexisting species responded to year-to-year climatic variability in different ways. Radial growth in junipers and pines responded positively to April and May temperatures, respectively. Summer drought constrained growth in both cases, although its impact was stronger on junipers than on pines. Our findings suggest that junipers respond earlier than pines to spring temperatures due to their prostrate morphology which may enhance a fast warming of their cambial meristems after snowmelt. The higher dependence of J. sabina on summer rainfall as compared with co-occurring pines confirms that drought stress negatively impacts secondary growth in Mediterranean mountains. This sensitivity to water availability may be caused by the juniper shallow root systems, which mainly use superficial soil water. The climatic signal registered in J. sabina allows studying the response of other similar shrubby woody species growing in Mediterranean alpine areas to the ongoing climate warming, which could also reduce water availability.     

Growth patterns in relation to drought-induced mortality at two Scots pine (Pinus sylvestris L.) sites in NE Iberian Peninsula

Drought-related tree mortality has become a widespread phenomenon. Scots pine (Pinus sylvestris L.) is a boreal species with high ecological amplitude that reaches its southwestern limit in the Iberian Peninsula. Thus, Iberian Scots pine populations are particularly good models to study the effects of the increase in aridity predicted by climate change models. A total of 78 living and 39 dead Scots pines trees were sampled at two sites located in the NE of the Iberian Peninsula, where recent mortality events have been recorded. Annual tree rings were used to (1) date dead trees; (2) investigate if there was an association between the occurrence of tree death and severe drought periods characterized by exceptionally low ratios of summer precipitation to potential evapotranspiration (P/PET); and (3) to compare the growth patterns of trees that died with those of surviving ones. Mixed models were used to describe the relationships between tree growth (in terms of basal area increment, BAI, and the percentage of latewood, LW%) and climate variables. Our results showed a direct association between Scots pine mortality and severe drought periods characterized by low summer water availability. At the two sites, the growth patterns of dead trees were clearly distinguishable from those of the trees that survived. In particular, the BAI of dead trees was more sensitive to climate dryness (low P/PET_summer, high temperatures) and started to decline below the values of surviving neighbors 15–40 years before the time of death, implying a slow process of growth decline preceding mortality.     

Towards a new approach for dendroprovenancing pines in the Mediterranean Iberian Peninsula

Dendroprovenancing studies frequently use site chronologies to identify the origin of archaeological and historical timber. However, radial growth (tree-ring width, TRW) of tree species is influenced by both local and regional climate scales. Here we investigate how the use of annually-resolved Blue Intensity (BI) measurements can enhance dendroprovenancing precision of black pine (Pinus nigra Arn.) and Scots pine (P. sylvestris L.) on the Iberian Peninsula. Principal Component Gradient Analyses (PCGA) was used to assess geographical patterns of annual variation in different TRW and BI proxies of pine trees from two mountain ranges in the Central System and Andalusia in Spain. Local climate-growth relationships were quantified to identify underlying causes of identified groups with diverse growth patterns. Two distinct elevational groups were observed when performing PCGA on latewood BI time series with the response to summer drought as the main factor causing the differences. Both P. nigra and P. sylvestris BI time series were found to be more related to summer drought at low-elevation sites showing an increase in sensitivity at lower latitudes. PCGA of TRW time series allowed to discriminate between trees from Andalusia and Central System within the elevation groups. February and October temperatures were found to be the main climatic factors causing the differences in TRW time series among the high- elevation sites, whereas for low-elevation trees it was the average winter temperature influencing TRW. A subsequent leave-one-out analyses confirmed that including latewood BI time series improves the precision of dendroprovenancing of pine wood in the Iberian Peninsula.     

Elevated growth temperatures alter hydraulic characteristics in trembling aspen (Populus tremuloides) seedlings: implications for tree drought tolerance

Although climate change will alter both soil water availability and evaporative demand, our understanding of how future climate conditions will alter tree hydraulic architecture is limited. Here, we demonstrate that growth at elevated temperatures (ambient +5 °C) affects hydraulic traits in seedlings of the deciduous boreal tree species Populus tremuloides, with the strength of the effect varying with the plant organ studied. Temperature altered the partitioning of hydraulic resistance, with greater resistance attributed to stems and less to roots in warm‐grown seedlings (P < 0.02), and a 46% (but marginally significant, P = 0.08) increase in whole plant conductance at elevated temperature. Vulnerability to cavitation was greater in leaves grown at high than at ambient temperatures, but vulnerability in stems was similar between treatments. A soil–plant–atmosphere (SPA) model suggests that these coordinated changes in hydraulic physiology would lead to more frequent drought stress and reduced water‐use efficiency in aspen that develop at warmer temperatures. Tissue‐specific trade‐offs in hydraulic traits in response to high growth temperatures would be difficult to detect when relying solely on whole plant measurements, but may have large‐scale ecological implications for plant water use, carbon cycling and, possibly, plant drought survival.     

From climate change predictions to actions – conserving vulnerable animal groups in hotspots at a regional scale

Current climate change is a major threat to biodiversity. Species unable to adapt or move will face local or global extinction and this is more likely to happen to species with narrow climatic and habitat requirements and limited dispersal abilities, such as amphibians and reptiles. Biodiversity losses are likely to be greatest in global biodiversity hotspots where climate change is fast, such as the Iberian Peninsula. Here we assess the impact of climate change on 37 endemic and nearly endemic herptiles of the Iberian Peninsula by predicting species distributions for three different times into the future (2020, 2050 and 2080) using an ensemble of bioclimatic models and different combinations of species dispersal ability, emission levels and global circulation models. Our results show that species with Atlantic affinities that occur mainly in the North‐western Iberian Peninsula have severely reduced future distributions. Up to 13 species may lose their entire potential distribution by 2080. Furthermore, our analysis indicates that the most critical period for the majority of these species will be the next decade. While there is considerable variability between the scenarios, we believe that our results provide a robust relative evaluation of climate change impacts among different species. Future evaluation of the vulnerability of individual species to climate change should account for their adaptive capacity to climate change, including factors such as physiological climate tolerance, geographical range size, local abundance, life cycle, behavioural and phenological adaptability, evolutionary potential and dispersal ability.     

一种濒危大疣蛛的潜在分布区域以及气候变暖的影响

本研究的目的是i)确定伊比利亚半岛一种大疣蛛(Macrothele calpeiana)分布的气候相关性以预测其潜在分布,ii)详细阐述该物种在伊比利亚半岛的分布假说,iii)通过推断模型预测确认该物种在北非和整个地中海地区的适合区域,iv)预测气候变暖对蜘蛛潜在分布区的影响。基于物种的存在、远离目前环境条件下的可能缺失以及其它的气候参数,使用广义线性模型发展了潜在分布的可预测模型。蜘蛛在伊比利亚半岛上的潜在分布远大于目前已知的分布区,延伸到尚未发现蜘蛛分布的葡萄牙广大地区。本文提出了该种大疣蛛在适合分布区域内没有分布的历史因素。北非具有适合该物种的条件但却没有该属物种的分布支持了大疣蛛(Macrothele)祖先的东方起源假说。对地中海地区蜘蛛分布的推断突出显示了阿根廷地区有合适的分布区,该地区也发现有另一种欧洲大疣蛛。气候变暖将对现存于伊比利亚的M.calpeiana种群产生负面影响,因为气候变暖将减少并破碎化蜘蛛在北非的潜在栖息地。目前,急需确认在葡萄牙广大地区是否存在蜘蛛物种,发展对该属的系统发育研究以确定大疣蛛属起源和扩散史的理论。     

Invasive species can handle higher leaf temperature under water stress than Mediterranean natives

Thermal tolerance of Photosystem II (PSII) highly influences plant distribution worldwide because it allows for photosynthesis during periods of high temperatures and water stress, which are common in most terrestrial ecosystems and particularly in dry and semi-arid ones. However, there is a lack of information about how this tolerance influences invasiveness of exotic species in ecosystems with seasonal drought. To address this question for Mediterranean-type ecosystems (MTE) of the Iberian Peninsula, we carried out an experiment with fifteen phylogenetically related species (8 invasive and 7 native, Pinus pinaster Ait., Pinus radiata D. Don, Schinus molle Linn., Elaeagnus angustifolia L., Eucalyptus globulus Labill., Acacia melanoxylon R. Br., Gleditsia triacanthos L., Pistacia terebinthus L., Rhamnus alaternus L., Anagyris foetida L., Colutea arborescens L., Oenothera biennis L., Epilobium hirsutum L., Achillea filipendulina Lam. and Achillea millefolium L). Seedlings were grown and maximal photochemical efficiency of PSII (Fv/Fm) was measured at two water availabilities (well-watered and with water stress). PSII thermal tolerance measurements were related to specific leaf area (SLA), which varied significantly across the study species, and to the mean potential evapotranspiration (PET) of the month with the lowest precipitation in the native areas of both groups and in the invaded area of the Iberian Peninsula. Additionally, PSII thermal tolerance measurements under water stress were phylogenetically explored. Invasive and native species neither differed in SLA nor in their thermal tolerance under well-watered conditions. For well-watered plants, SLA was significantly and positively related to PSII thermal tolerance when all species were explored together regardless of their invasive nature. However, this relationship did not persist under water stress and invasive species had higher plastic responses than Mediterranean natives resulting in higher leaf temperatures. Higher PSII thermal tolerance could explain invasiveness because it allows for longer periods of carbon acquisition under water stress. In fact, PSII thermal tolerance was positively related to the PET of the invaded and native areas of the Iberian Peninsula. PSII thermal tolerance was not related to PET at the native range of the invasive species, suggesting that successful invasive species were plastic enough to cope with novel dry conditions of the Iberian Peninsula. Moreover, our phylogenetic results indicate that future scenarios of increased aridity in MTE associated to climate change will filter invasion success by taxonomic identity. This study reveals the importance of studying ecophysiological traits to understand and better predict future biological invasions.     

The Iberian Peninsula as a potential source for the plant species pool in Germany under projected climate change

The application of niche-based modelling techniques to plant species has not been explored for the majority of taxa in Europe, primarily due to the lack of adequate distributional data. However, it is of crucial importance for conservation adaptation decisions to assess and quantify the likely pool of species capable of colonising a particular region under altered future climate conditions. We here present a novel method that combines the species pool concept and information about shifts in analogous multidimensional climate space. This allows us to identify regions in Europe with a current climate which is similar to that projected for future time periods in Germany. We compared the extent and spatial location of climatically analogous European regions for three projected greenhouse gas emission scenarios in Germany for the time period 2071–2080 (+2.4°C, +3.3°C, +4.5°C average increase in mean annual temperature) to those of the recent past in Europe (1961–90). Across all three scenarios, European land areas which are characterised by climatic conditions analogue to those found in Germany decreased from 14% in 1961–1990 to ca. 10% in 2071–2080. All scenarios show disappearing current climate types in Germany, which can mainly be explained with a general northwards shift of climatically analogous regions. We estimated the size of the potential species pool of these analogous regions using floristic inventory data for the Iberian Peninsula as 2,354 plant species. The identified species pool in Germany indicates a change towards warmth and drought adapted southern species. About one-third of the species from the Iberian analogous regions are currently already present in Germany. Depending on the scenario used, 1,372 (+2.4°C average change of mean annual temperature), 1,399 (+3.3°C) and 1,444 (+4.5°C) species currently not found in Germany, occur in Iberian regions which are climatically analogous to German 2071–80 climate types. We believe that our study presents a useful approach to illustrate and quantify the potential size and spatial distribution of a pool of species potentially colonising new areas under changing climatic conditions.     

Forest composition in Mediterranean mountains is projected to shift along the entire elevational gradient under climate change

Aim Species distribution models have been used frequently to assess the effects of climate change on mountain biodiversity. However, the value and accuracy of these assessments have been hampered by the use of low‐resolution data for species distributions and climatic conditions. Herein we assess potential changes in the distribution and community composition of tree species in two mountainous regions of Spain under specific scenarios of climate change using data with a high spatial resolution. We also describe potential changes in species distributions and tree communities along the entire elevational gradient. Location Two mountain ranges in southern Europe: the Central Mountain Range (central west of the Iberian Peninsula), and the Iberian Mountain Range (central east). Methods We modelled current and future distributions of 15 tree species (Eurosiberian, sub‐Mediterranean and Mediterranean species) as functions of climate, lithology and availability of soil water using generalized linear models (logistic regression) and machine learning models (gradient boosting). Using multivariate ordination of a matrix of presence/absence of tree species obtained under two Intergovernmental Panel on Climate Change (IPCC) scenarios (A2 and B2) for two different periods in the future (2041–70 and 2071–2100), we assessed the predicted changes in the composition of tree communities. Results The models predicted an upward migration of communities of Mediterranean trees to higher elevations and an associated decline in communities of temperate or cold‐adapted trees during the 21st century. It was predicted that 80–99% of the area that shows a climate suitable for cold–wet‐optimum Eurosiberian coniferous and broad‐leaved species will be lost. The largest overall changes were predicted for Mediterranean species found currently at low elevations, such as Pinus halepensis, Pinus pinaster, Quercus ilex ssp. ballota and Juniperus oxycedrus, with sharp increases in their range of 350%. Main conclusions It is likely that areas with climatic conditions suitable for cold‐adapted species will decrease significantly under climate warming. Large changes in species ranges and forest communities might occur, not only at high elevations within Mediterranean mountains but also along the entire elevational gradient throughout this region, particularly at low and mid‐elevations. Mediterranean mountains might lose their key role as refugia for cold‐adapted species and thus an important part of their genetic heritage.     

Iberian–Balearic fern regions and their explanatory variables

This article delineates the compositional regions present in the Iberian–Balearic fern flora and compares these regions to previously proposed biogeographic units. It also assesses the extent to which environmental variables could explain the regions and the fern species richness gradients found within them. A combination of 40 previously published and new maps were used to compile the distribution of 123 pteridophytes on a 50 × 50 km UTM grid. Cluster analysis of the resulting 257 squares was used to classify 10 regions based on fern species assemblages. Discriminant function analysis identified the environmental variables that best explained these fern composition regions. Using generalized linear models; the number of species in each square was regressed against topography, climate, geology, environmental diversity, land use and spatial variables within each region. Two main latitudinal pteridophyte zones can be recognized in the Iberian Peninsula. These two zones are longitudinally subdivided into two sub zones. The 10 regions established significantly differ both in species richness and influential environmental variables. Climatic variables discriminate the most among regions, followed by topography, heterogeneity and geology. Pteridophyte richness varies, with richer areas being located along the coast and the main mountain ranges and the poorest areas being in the central plateaus and some north eastern and south western river basins. Species richness variation in Iberia is positively correlated with altitude range, precipitation, maximum altitude and area with siliceous soils. It is negatively correlated with the total annual days of sun, however. The fact that species richness is explained by different variables within each of the 10 regions indicates that the specific factors determining the spatial distribution of species richness vary from region to region. Some coastal regions are poorly explained by the model, and display a negative correlation with the selected causal factors. This finding suggests that persistent historic effects might play a local role in determining species assemblages in these regions. An erratum to this article can be found at     

Seed germination of high mountain Mediterranean species: altitudinal,interpopulation and interannual variability

The germination response of 20 species from high altitude Mediterranean climates, most of them rare endemics, was studied. Our main goal was to model the germination response of a complete set of Iberian high mountain species. The effect of temperature and other parameters, such as spatial and temporal short gradients, on germination were also evaluated. Some seed features (mass and size) were also related to the germination response. Finally, we tested the effect of cold-wet stratification pretreatment when germination was low under natural conditions. Seeds were collected at four locations from 1,900 to 2,400 m a.s.l. in the Sierra de Guadarrama (Spanish Central Range) over two consecutive growing seasons (2001–2002) and submitted to different temperatures and a constant photoperiod of 16 h light/8 h darkness. Most plants readily germinate without treatment, reaching an optimum at relatively high temperatures in contrast to lowland Mediterranean species. Seeds seem to be physiologically prepared for rapid germination even though these plants usually face very intense summer droughts after ripening and dispersal. Germination was also highly variable among altitudes, populations and years, but results were inconsistent among species. Such flexibility could be interpreted as an efficient survival strategy for species growing under unpredictable environments, such as the Mediterranean climate. Finally cold-wet stratification increased germination capacity in five of nine dormant species, as widely reported for many arctic, boreal and alpine species. In conclusion, high mountain Mediterranean species do not differ from alpine species except that a relatively high number of species are ready to germinate without any treatment.     

Refugia within refugia – patterns in endemism and genetic divergence are linked to Late Quaternary climate stability in the Iberian Peninsula

In Europe, southern peninsulas served as major refugia during Pleistocene cold periods. However, growing evidence has revealed complex patterns of glacial survival within these southern regions, with multiple glacial refugia within each larger refugial area. We investigated the extent to which patterns of endemism and phylogeographic are concordant across animal species in the Iberian Peninsula, one of the most important unglaciated areas in Europe during the Pleistocene, can be explained in terms of climatic stability. We found that historical climatic stability (notably climate velocity measures integrating macroclimatic shifts with local spatial topoclimate gradients) was often among the most important predictors of endemic species richness for different taxonomic groups using models that also incorporated measures of modern climate. Furthermore, for some taxonomic groups, climatic stability was also correlated with patterns of spatial concordance in interpopulation genetic divergence across multiple taxa, and private haplotypes were more frequently found in relatively stable areas. Overall, our results suggest that both endemism patterns and cross‐taxa concordant phylogeographic patterns across the Iberian Peninsula to some extent are linked to spatial variation in Late Quaternary climate stability, in agreement with the proposed ‘refugia‐within‐refugia’ scenario. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 13–28.     

Late Quaternary dynamics of pinewoods in the Iberian Mountains

The role of pinewoods as native forests in the Iberian Mountains, and their long-term dynamics during the last interglacial, has been intensely debated among geobotanists. This debate has resulted in several different hypotheses regarding the interpretation of the present day landscape.Recent research on Late Quaternary palaeoecological records has enabled long-term patterns of forest dynamics in the main ranges of the Iberian Peninsula to be tested, and the parallel analysis of micro- (mainly pollen) and macroremains (woods, charcoals, fruits, seeds and leaves) has enhanced the resolution of these palaeobiological records. Additional historical information has allowed a complete overview of the past vegetal landscapes to be obtained.This work summarises the available data for Iberian mountain pines during the Lateglacial and the Holocene, focussing on the mountain regions in scenarios of absence or dominance. Based on this overview, life history traits and patterns of plant dynamics during the Holocene are discussed and compared with present landscapes.In the long term, Pinus does not always respond as a serial element in succession dynamics, not even in very favourable environments for hardwoods. Processes such as incumbency or resilience, and features such as frugality and their ability to disperse, affect the persistence of pines to the present day. This is exemplified for continental mountain areas, in which the absence of anthropogenic activities could have determined the wider coverage of pinewoods seen today.     

Dispersal response to climate change: scaling down to intraspecific variation

Range shift, a widespread response to climate change, will depend on species abilities to withstand warmer climates. However, these abilities may vary within species and such intraspecific variation can strongly impact species responses to climate change. Facing warmer climates, individuals should disperse according to their thermal optimum with consequences for species range shifts. Here, we studied individual dispersal of a reptile in response to climate warming and preferred temperature using a semi‐natural warming experiment. Individuals with low preferred temperatures dispersed more from warmer semi‐natural habitats, whereas individuals with higher preferred temperatures dispersed more from cooler habitats. These dispersal decisions partly matched phenotype‐dependent survival rates in the different thermal habitats, suggesting adaptive dispersal decisions. This process should result into a spatial segregation of thermal phenotypes along species moving ranges which should facilitate local adaptation to warming climates. We therefore call for range shift models including intraspecific variation in thermal phenotype and dispersal decision.     

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

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.