caa a22 4500 475751523 CHVBK 20180406123525.0 cr unu---uuuuu 170329e20000501xx s 000 0 eng 10.1023/A:1009801614786 doi (NATIONALLICENCE)springer-10.1023/A:1009801614786 The influence of hybridization on epidermal properties of birch species and the consequences for palaeoclimatic interpretations [Elektronische Daten] [Friederike Wagner, Seppo Neuvonen, Wolfram Kürschner, Henk Visscher] The Fennoscandian birch population primarily consists of Betula nana, B. pendula and B. pubescens ssp. czerepanovii, the Mountain birch. Frequent hybridization between the Mountain birch and B. nana generates a wide range of genotypic and phenotypic plasticity in the subarctic birch zone of Fennoscandia. Phases of subarctic conditions prevailed during the Late Glacial in large parts of NW Europe, and palynological as well as macrofossil analysis provide some evidence for the occurrence of birch hybrids during these intervals. Leaves from genetically controlled specimens of Betula pendula, B. pubescens ssp. czerepanovii, B. nana and the hybrids B. pubescens ssp. czerepanovii × nana and B. nana × pubescens ssp. czerepanovii are investigated for their specific characteristics of the epidermis morphology. Frequency and size of epidermal cells and stomata reveal a close affinity of both hybrids to B. nana and allow a differentiation of the intermediate forms between B. nana and the Mountain birch. With respect to palaeoatmospheric CO2 reconstructions based on stomatal index, epidermal analysis shows that a possible occurrence of hybrids in fossil leaf assemblages has no profound consequences for combined species records. However, the significant differences observed in B. nana demand the separation of this species. A comparison of the cuticle properties of B. pendula and B. pubescens from Finnish Lapland and leaf material from The Netherlands reveals a divergence of the stomatal index that may be due to differences in day light length. Kluwer Academic Publishers, 2000 Epidermal properties nationallicence Birch hybridization nationallicence Stomatal index nationallicence Stomatal density nationallicence Palaeoatmospheric CO2 nationallicence Wagner Friederike Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584, CD Utrecht, The Netherlands aut Neuvonen Seppo Kevo Subarctic Research Institute, University of Turku, 20014, Turku, Finland aut Kürschner Wolfram Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584, CD Utrecht, The Netherlands aut Visscher Henk Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584, CD Utrecht, The Netherlands aut Plant Ecology Kluwer Academic Publishers 148/1(2000-05-01), 61-69 1385-0237 148:1<61 2000 148 11258 https://doi.org/10.1023/A:1009801614786 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1009801614786 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wagner Friederike Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584, CD Utrecht, The Netherlands aut NATIONALLICENCE 700 1- Neuvonen Seppo Kevo Subarctic Research Institute, University of Turku, 20014, Turku, Finland aut NATIONALLICENCE 700 1- Kürschner Wolfram Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584, CD Utrecht, The Netherlands aut NATIONALLICENCE 700 1- Visscher Henk Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584, CD Utrecht, The Netherlands aut NATIONALLICENCE 773 0- Plant Ecology Kluwer Academic Publishers 148/1(2000-05-01), 61-69 1385-0237 148:1<61 2000 148 11258 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer