History of Environmental and Climatic Changes Recorded in Lacustrine Sediments—A Wigry Lake Case Study

Abstract

Wigry Lake represents one of the most beautiful and valuable postglacial lakes that is located in the north-eastern part of Poland. It has been an object of scientific interest for over a century, but the most intense period of research started in 1997 and resulted in the production of numerous papers of a multidisciplinary range. The lake is especially well analyzed in terms of its sediments, which were studied using geophysical methods and using traditional lake cartography based on the sampling of sediments and their geochemical characterization. Nearly two decades of research has resulted in the extraction of over 1200 sediment samples, which facilitated the analysis and the description of five main sediment types that can be found at the bottom of Wigry Lake, i.e., carbonate gyttja, lacustrine chalk, clastic sediment, fluvial-lacustrine sediment, and organic gyttja. A very thorough vertical as well as spatial examination of Wigry Lake sediments, together with paleobiological research and isotopic dating, allowed researchers to analyze the history of environmental changes in the lake and its immediate vicinity, including anthropogenic changes. Wigry Lake had been preserved as a pristine lake for a long time, and, despite the significant growth of anthropopressure, which began in the 17th century and intensified in the 20th century, it retained its natural character to a large extent. This was possible mainly due to the favorable morphometry of the lake (large depth and capacity of the reservoir) and different forms of active and passive protection, introduced mainly after the establishment of the Wigry National Park in 1989.