The Perspective of Arctic-Alpine Species in Southernmost Localities: The Example of Kalmia procumbens in the Pyrenees and Carpathians.

High-mountain and arctic plants are considered especially sensitive to climate change because of their close adaptation to the cold environment. Kalmia procumbens, a typical arctic-alpine species, reaches southernmost European localities in the Pyrenees and Carpathians. The aim of this study was the assessment and comparison of the current potential niche areas of K. procumbens in the Pyrenees and Carpathians and their possible reduction due to climate change, depending on the scenario. The realized niches of K. procumbens in the Pyrenees are compact, while those in the Carpathians are dispersed. In both mountain chains, the species occurs in the alpine and subalpine vegetation belts, going down to elevations of about 1500-1600 m, while the most elevated localities in the Pyrenees are at ca. 3000 m, about 500 m higher than those in the Carpathians. The localities of K. procumbens in the Carpathians have a more continental climate than those in the Pyrenees, with lower precipitation and temperatures but higher seasonality of temperature and precipitation. The species covered a larger area of geographic range during the Last Glacial Maximum, but its geographic range was reduced during the mid-Holocene. Due to climate warming, a reduction in the potential area of occurrence could be expected in 2100; this reduction is expected to be strong in the Carpathians and moderate in the Pyrenees.

Morphological versus molecular markers to describe variability in Juniperus excelsa subsp. excelsa (Cupressaceae).

BACKGROUND AND AIMS: Juniperus excelsa M.-Bieb. is a major forest element in the mountains of the eastern part of Mediterranean and sub-Mediterranean regions. This study comprises the first morphological investigation covering a large part of the geographical range of J. excelsa and aims to verify the congruency between the morphological results and molecular results of a previous study. METHODOLOGY: We studied 14 populations sampled from Greece, Cyprus, Ukraine, Turkey and Lebanon, 11 of which have previously been investigated using molecular markers. Three hundred and ninety-four individuals of J. excelsa were examined using nine biometric features characterizing cones, seeds and shoots, and eight derived ratios. Statistical analyses were conducted in order to evaluate the intra- and inter-population morphological variability. PRINCIPAL RESULTS: The level of intra-population variability observed did not show any geographical trends. The total variation mostly depended on the ratios of cone diameter/seed width and seed width/seed length. The discrimination analysis, the Ward agglomeration method and barrier analysis results showed a separation of the sampled populations into three main clusters. These results confirmed, in part, the geographical differentiation revealed by molecular markers with a lower level of differentiation and a less clear geographical pattern. The most differentiated populations using both markers corresponded to old, isolated populations in the high altitudes of Lebanon (>2000 m). Moreover, a separation of the northern Turkish population from the southern Turkish populations was observed using both markers. CONCLUSIONS: Morphological variation together with genetic and biogeographic studies make an effective tool for detecting relict plant populations and also populations subjected to more intensive selection.