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During the Pleistocene glacial periods, the ranges of many temperate species in Europe contracted southwards to refugia near the Mediterranean Basin. This study tested the 'expansion--contraction' model by applying the ecological niche modelling approach to one widespread temperate tree species, pedunculate oak, Quercus robur L., distributed across Europe and Anatolia. We projected the distribution of Q. robur under climatic conditions of the Present, the mid-Holocene [HOL, c. 6000 years before present (YBP)], the Last Glacial Maximum (LGM, c. 22 000 YBP) and the Last Interglacial (LIG, c. 130 000 YBP). Quercus robur was at equilibrium with the climate as the model prediction was highly compatible with the its known distribution range under present bioclimatic conditions. The LIG and the HOL predictions gave a much broader distribution range than that during the LGM, suggesting its range contracted towards favourable areas in southern Europe and Anatolia. The results indicate that the glacial refugia hypothesis, based mainly on the 'expansion--contraction' model, applies to Q. robur, although possible extra-Mediterranean refugia in northern, western and southern France are also identified. This study therefore supports claims that European biogeography is significantly more complex than previously thought. [ABSTRACT FROM AUTHOR]

Despite its biological richness, Anatolian steppe ecosystem is currently under threat because of human activity. Anatolian steppe vegetation had been shaped by natural disturbances such as fire and grazing in the past but has been subjected to anthropogenic disturbances such as agriculture and domestic grazing due to increased human activity since a few thousands of years. In this study, it is suggested that the inverse relationship between fire and grazing is also present in Anatolian steppes, and therefore that socio-economic changes occurring in our time will affect disturbance regimes proceeding in this ecosystem in future. For gathering ecological information guided to the conservation of Anatolian steppes, it is needed to perform ecological experiments and to explore disturbance dynamics. [ABSTRACT FROM AUTHOR]