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

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The present study aims to review palaeoecological evidence for environmental changes induced by human activities over the last few millennia in the montane landscapes of Morocco. The study is based on well-dated pollen and geochemical records from the Rif and the Middle Atlas mountains, to show spatial and temporal variation in the onset and intensity of exploitation of forest, soil and mineral resources. Before ca. 2000 BP, anthropogenic impact was minimal. At about that time, abrupt changes of the arboreal pollen proportions, with a decline in all tree taxa, indicate a reduction of the forest cover interpreted as being anthropogenic. In the Rif Mountains, increased influx of carbonates (Ca) in the sedimentary records indicates enhanced soil erosion coincident with the reduction in tree cover. In the Middle Atlas, reduced forest cover is linked to geochemical evidence for mining and metallurgy of lead (Pb), copper (Cu) and zinc (Zn). These industrial activities correspond to the expansion of the Roman Empire into Morocco at around AD 40 and show a decline when the Romans were displaced by the Vandals about five centuries later

Cedrus atlantica (Atlas cedar) is a relict and endemic endangered species from northwestern African mountains, whose distribution range has undergone a dramatic reduction over recent decades. Long-term studies are needed for a better understanding of the development of its range as well as for assisting in the implementation of sustainable conservation measures. The multi-proxy analysis of a high-resolution fossil record of 180 cm depth allowed us to depict the final demise of an Atlas cedar population from the western Rif Mountains (Jbel Khesana), despite its high resilience during the last ~4000 years. Currently, Atlas cedar trees are not observed in Jbel Khesana but they still occur in the nearby area as scattered populations on a few mountain tops at altitudes higher than 1400 m a.s.l. Our data show an initial relatively stable period (~4000–2400 cal. yr BP) followed by a phase where both climatic and human-induced disturbances cause an alternate dominance of oaks and Atlas cedars (2400~1550 cal. yr BP). Then, the increasing aridity and human activities favoured the depletion of Atlas cedar forests (~1550–800 cal. yr BP). Our record shows that Atlas cedar forests have recovered after each deforestation event, which reveals a high resilience of the species until the mid-20th century, when they became extinct in the study area. The main driver of their local extinction may be attributed to the strong human pressure. Management measures of Atlas cedar in the Rif Mountains should aim at limiting intensive loggings and protecting the existing populations for their local regeneration.

The use of fire and, consequently, its severity and incidence on the environment have grown steadily during the last millennia throughout the Mediterranean. This issue can be assessed in several mountain ranges of central Iberia where changes in the management policy on anthropic activities and exploitation of high‐mountain environments have promoted a remarkable increase on fire frequency. Our research focuses on fire dynamics throughout the last 3,000 years from three peat bog charcoal records of the Gredos range (central Iberia). Our aim is to reconstruct past fire regimes according to forest vegetation typology (Castanea sativa, Pinus pinaster, and Pinus sylvestris). Charcoal influx shows low values between 3,140 and 1,800 cal. year bp when forests were relatively dense in both high and mid‐mountain areas. Fire appeared synchronous between 1,800 and 1,700 cal. year bp for Lanzahíta and Serranillos and around 1,400–1,240 cal. year bp for the three sites, suggesting anthropogenic fire control between the Late Roman and Visigothic periods that can be related to the cultivation of olive trees in the valleys and a greater human impact in high‐mountain areas. By contrast, during the Muslim period (1,240–850 cal. year bp), fire dynamics becomes asynchronous. Later, fires turn again coeval in the Gredos range during the Christian period (850–500 cal. year bp) and can be also correlated with drought phases during the Late Medieval Warm Episode. In short, our study demonstrates that fire activity has been enormously variable during the late Holocene in response to both short‐term and long‐term regional and global climate, vegetation dynamics, and land use changes. Copyright © 2017 John Wiley & Sons, Ltd.