Preface &amp;quot;Evolutionary and geological history of the Balkan lakes Ohrid and Prespa&amp;quot;

B Wagner,T Wilke

doi:10.5194/bg-8-995-2011

Abstract

Worldwide only very few freshwater lakes exist that are characterised by a long geological history, often leading to an outstanding degree of endemic biodiversity. Examples include Lake Baikal located in Siberia, Lake Titicaca in South America, and lakes Tanganyika and Malawi in the East African Rift. Most of such “old” lakes have a tectonic origin and are located in regions, wich are still tectonically active. Two famous representatives of such lakes in Europe are the small “sister lakes” Prespa and Ohrid on the Balkan Peninsula. Lake Ohrid has today a surface area of 358 km2, a maximum water depth of 289 m, a mean water depth of 155 m, and a volume of 55 km3 (Matzinger et al., 2006). The surface area of neighbouring Lake Prespa is only 254 km2, its maximum and mean water depths are 58 m and 14 m, respectively, and its volume is 3.6 km3 (Matzinger et al., 2006; Albrecht and Wilke, 2008). The shortest straight line distance between the two lakes is 9 km and Lake Prespa (altitude 849 m a.s.l.) is connected hydrologically with Lake Ohrid (altitude 693 m a.s.l.) via underground karstic channels.

Highlights

Worldwide only very few freshwater lakes exist that are characterised by a long geological history, often leading to an outstanding degree of endemic biodiversity
From a geological point of view, the tectonic origin and ongoing tectonic activities of the Prespa and Ohrid basins are confirmed by field observations and recent earthquake data (e.g., Hoffmann et al, 20101)
The outstanding degree of biodiversity, on one side, and the “creeping biodiversity crises” in lakes Ohrid and Prespa, on the other side, have spurred a wealth of biological and ecological studies, they have promoted intensive interdisciplinary research combining geological, hydrological, sedimentological, and climatic approaches aiming at understanding the evolution of lakes Ohrid and Prespa in general, and climate dynamics and driving forces for the high degree of biodiversity in particular

Summary

Introduction

Worldwide only very few freshwater lakes exist that are characterised by a long geological history, often leading to an outstanding degree of endemic biodiversity. Examples include Lake Baikal located in Siberia, Lake Titicaca in South America, and lakes Tanganyika and Malawi in the East African Rift. Most of such “old” lakes have a tectonic origin and are located in regions, wich are still tectonically active. Lake Ohrid has today a surface area of 358 km, a maximum water depth of 289 m, a mean water depth of 155 m, and a volume of 55 km (Matzinger et al, 2006). The surface area of neighbouring Lake Prespa is only 254 km, its maximum and mean water depths are 58 m and 14 m, respectively, and its volume is 3.6 km (Matzinger et al, 2006; Albrecht and Wilke, 2008). The shortest straight line distance between the two lakes is 9 km and Lake Prespa (altitude 849 m a.s.l.) is connected hydrologically with Lake Ohrid (altitude 693 m a.s.l.) via underground karstic channels

Ancient lakes Ohrid and Prespa: hotspots of endemic biodiversity

Sedimentology and tephrostratigraphy

Climate dynamics

Outlook