Landscape Development and Climate Change in Southwest Bulgaria (Pirin Mountains) wwwwwww Karsten Grunewald Jörg Scheithauer ● Landscape Development and Climate Change in Southwest Bulgaria (Pirin Mountains) Karsten Grunewald Jörg Scheithauer Leibniz Institute of Ecological and Regional Landscape Research Centre Development Dresden Dresden Germany Germany [email protected] [email protected] ISBN 978-90-481-9958-7 e-ISBN 978-90-481-9959-4 DOI 10.1007/978-90-481-9959-4 Springer Dordrecht Heidelberg London New York © Springer Science+Business Media B.V. 2011 No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Preface Tell me the past and I’ll see the future. Confucius Southeast Europe, the Balkans and not least the southwest Bulgarian Pirin region experienced an eventful natural and cultural history covering a time scale from millenia to the decades of the Younger Past, which has to be decrypted. Information on the Pirin mountains, stored in geo-archives, has been examined using modern methods and with great effort. This monograph seeks to summarize information on landscape and climate development in the region. For the Holocene period, the last 10,000 years or so, the forest and climate history of the mountain regions was reconstructed using pollen analysis of lake sediments and peat. The extensive work of Bulgarian colleagues was analyzed and supplemented with soil surveys. Our examination focused on an archive network in the Alpine timberline zone of the northern Pirins. This network provides tree-ring analyses of centuries-old soil and moraine investigations, firn and ice layers of recent glaciers, and cultural- history inquiries, as well as analyses of relatively long-time climate data series. Thus, the climate, including its extremes, can be described in relatively high resolu- tion, for the last 500 years. The studies were conducted with the support of the German Research Foundation (DFG) and the German Academic Exchange Service (DAAD), as well as the administration of Pirin National Park. We wish to thank our co-workers and colleagues, namely Sieglinde Gerstenhauer, Alexander Gikov, Bjorn Günther, Dr. Gerhard Helle, Alexander Hennig, Dr. Jürgen König, Dr. Christiana Weber, Thomas Wieloch, Beate Winkler, and students too numerous to be named here, for their assistance with digging and drilling, mapping, sampling and lab analyses. A German version of the book was published first (www.rhombos.de). We thank Mr. Reiser for helping us with the authorisation chores. v vi Preface Anne Scheithauer, Laura Grunewald and Silka Halmel: thank you for helping with the English text. Actual developments and findings were incorporated by us, especially regarding glaciers and dendrology. We would also like to express our gratitude to Margaret Deignan of the Environment Science Unit of Springer for her brilliant publishing support and R. Samuel, project manager at SPi Technologies India Pvt Ltd, who handled the book production and language polishing. Dresden Karsten Grunewald Jörg Scheithauer Contents 1 Geoarchives – Why View the Past? ......................................................... 1 1.1 Introduction and Objectives ............................................................... 1 1.2 Reasons and Scales for Climate Changes .......................................... 5 1.3 Archives and Methods ....................................................................... 6 References ................................................................................................... 8 2 The Pirin Mountains as a Model Region ............................................... 11 2.1 Location and Ecosystem Characteristics ........................................... 11 2.2 Geology and Morphodynamic ........................................................... 13 2.3 Water in the Pirin Mountains ............................................................. 19 2.4 Soil and Biosphere ............................................................................. 21 2.5 Pirin National Park – Potentials and Anthropogenic Interference ........................................................................................ 26 References ................................................................................................... 29 3 Holocene Climate and Landscape Chronology ...................................... 33 3.1 Würm Glaciation and Late-Glacial Development ............................. 33 3.2 Climate and Vegetation During the Holocene.................................... 39 3.2.1 Early Holocene (Preboreal, Boreal) ....................................... 41 3.2.2 Mid Holocene (Atlantic) ........................................................ 42 3.2.3 Late Holocene (Subboreal, Subatlantic) ................................ 43 3.3 Outline of Cultural-Historical Dynamics ........................................... 48 3.3.1 Würm Glaciation .................................................................... 48 3.3.2 Boreal and Atlantikum (10,200–4,800 BP) ........................... 48 3.3.3 Bronze Age and Ice Age ........................................................ 49 3.3.4 Roman Empire (2,300–1,600 BP) .......................................... 49 3.3.5 The Migration Period (Fourth–Sixth Century) ...................... 51 3.3.6 The Golden Bulgarian Period (Seventh–Eleventh Century) .................................................. 51 3.3.7 Medieval Warmth Optimum (1000–1230) – Also in Bulgaria? ........................................... 52 vii viii Contents 3.3.8 Contemporary Climate Pessimum (1330; Particularly 1550–1850): The “Little Ice Age”. ..................... 53 3.3.9 Contemporary Thermal Optimum (Since 1850) .................... 55 References ................................................................................................... 56 4 Climate Data and Geo-Archives of the Recent Past .............................. 61 4.1 Characterization of Contemporary Local Climate Change ................ 61 4.1.1 Introduction ............................................................................ 61 4.1.2 Analysis of Meteorological Observations .............................. 62 4.1.3 Regional Climate Aspects ...................................................... 63 4.1.4 Climate Change and Climate Trend ....................................... 70 4.2 Pirin’s Glacier Features as a Climate Indicator .................................. 74 4.2.1 Introduction ............................................................................ 74 4.2.2 The Recent Glaciation of High Mountains in Southeastern Europe .......................................................... 75 4.2.3 Investigation Methods and Application to Snezhnika Glacieret ........................................................... 80 4.2.4 The Response to Climate Change .......................................... 90 4.3 The Timberline Ecotones as Key ....................................................... 92 4.3.1 Introduction ............................................................................ 92 4.3.2 Timberline Characteristics of the Northern Pirin Study Area ..................................................................... 94 4.4 Dendroecology of Pinus heldreichii .................................................. 101 4.4.1 Conifers as Geoarchives ......................................................... 101 4.4.2 Methodological Approach ..................................................... 103 4.4.3 Development of Chronologies ............................................... 105 4.4.4 Climate Growth Relation ....................................................... 108 References ................................................................................................... 114 5 Specifics of the Regional Climate and Landscape History .................... 123 5.1 Changes on the Millennial Timescale ................................................ 123 5.2 Climate Development of the Region During Younger Modern History .................................................................................. 126 5.3 The Recent Climate Change .............................................................. 131 References ................................................................................................... 134 6 Conclusion and Outlook .......................................................................... 137 References ................................................................................................... 146 Abbreviations .................................................................................................. 149 Index ................................................................................................................. 151 Chapter 1 Geoarchives – Why View the Past? Abstract Comprehensive knowledge of climate and landscape dynamics is essential to obtain a basic understanding of the recent geoecological situation and to assess possible future developments. High mountains and their ecosystems offer an outstanding opportunity for studies on the impact of climate change. The Pirin Mountains in Southeast Europe, situated at the transition between temper- ate and Mediterranean climate, are considered very sensitive to historical and current global changes. To evaluate the current situation, the existing climate proxy data sets need to be amended by precisely dated and highly time-resolved geoarchives spanning past centuries. Thus, the examination aims to reconstruct climate variability on different time scales, allowing us to improve the regional and sub-regional knowledge of facts and ecosystem services due to trends of global climate change. Keywords Climate and landscape development • Geoarchives • Methods • Southwest Bulgaria 1.1 Introduction and Objectives The anthropogenic change of the natural and cultural landscape increasingly affects ecosystems throughout the world on a regional and global scale. Resulting ecologi- cal and economic developments need to be recorded and, if possible, sustainably assessed. Therefore a comprehensive understanding of the structure, function and dynamic nature of these ecosystems is essential. Our working group carried out such investigations in southeastern Europe for several years (Grunewald and Stoilov 1998; Grunewald et al. 1999, 2007; Grunewald and Scheithauer 2008a). The center of interest is the northern Pirin and its flanking basins and valleys. Due to the biodiversity, this area can be regarded as an important refuge (Griffiths et al. 2004). The highest areas are most affected by the pressure of land use and also by climatic alteration. The ecosystem structures, K. Grunewald and J. Scheithauer, Landscape Development and Climate Change 1 in Southwest Bulgaria (Pirin Mountains), DOI 10.1007/978-90-481-9959-4_1, © Springer Science+Business Media B.V. 2011