Transect Studies on Pine Forests Along Parallel 52 ° North , 12 - 32 ° East and Along a Pollution Gradient in Poland : General Assumptions

The responses of pine forest to changing climate and environmental chemistry were studied along two transects following the pollution and continentality gradients in Poland. One axis begins on the western border of Poland, crosses the country along the 52nd parallel, and ends on the eastern border of Poland in the area of Bialowieza National Park, Biosphere Reserve. The second axis begins in industrial Upper Silesia in southwestern Poland and ends at the same point in the Bialowieza area on the eastern border of Poland. The west-east latitudinal transect follows the gradient of cooling and continentality, whereas the Silesian transect follows the pollution gradient. The extension of the continental transect to the west (Germany) and the east (Belarus) was possible after 2 years of the program. This “large transect” covers 20° of latitude, with a difference in mean annual temperature of 3.5 °C. The general assumptions of this program, e.g., philosophy of gradient/transect studies, selected global change scenarios, current climatic conditions, and air pollution exposure in central Europe, are reviewed. The International Geosphere Biosphere Program on Global Change predicted temperature increases of 1.5-2 °C in our climatic zone, which are close to the difference in thermoclimate registered along the transects in this study. In the description of transects, Polish systems of forest monitoring and procedures used for stand selection are introduced. The phytosociological characteristics of the studied stands and their position in the classification of vegetation has been determined, as well as some of the present changes in pollutant distribution. Introduction Because pollution in Silesia is clearly elevated but has steadily decreased in recent years, it is important to understand changes in local sources of contamination and their impact on Polish forests. Our transect studies are an attempt to relate the field test of pine forest responses to global warming. Because central European pine forests are seriously affected by air contamination, we try to include in the same program the influence of pollutants on forest behavior. Sites distributed along twoaxis transects were studied (fig. 1). One axis begins on the western border of Poland, crosses the country along the 52nd parallel, and ends on the eastern border of Poland in the area of Bialowieza National Parks, Biosphere Reserve. The second axis begins in industrial Upper Silesia in southwestern Poland and ends at the same point in the Bialowieza area on the eastern border of Poland. The west-east latitudinal transect follows the gradient of cooling and continentality, whereas the Silesian transect follows the pollution gradient. The extension of the continental transect to the west (Germany) and the east (Belarus) was possible after 2 years of the program. This “large transect” covers 20° of latitude, with a difference in mean annual temperature of 3.5 °C. This paper studies the phytosociological characteristics of pine stands, their position in the classification of vegetation, and some of the present changes in pollutant distribution in order to analyze the process of pollution transect selection and assumptions about its use as a research tool. General Assumptions The change in global climate anticipated and most probably occurring now is expected to produce changes in the functioning of terrestrial ecosystems. The very rich ecological literature dealing with this subject has resulted in the development of a variety of proposed methods to evaluate changes in ecosystems. These include Transect Studies on Pine Forests Along Parallel 52° North, 12-32° East and Along a Pollution Gradient in Poland: General Assumptions1 1 An abbreviated version of this paper was presented at the International Symposium on Air Pollution and Climate Change Effects on Forest Ecosystems, February 5-9, 1996, Riverside, California. 2 Ecologist, Institute of Geography and Spatial Organization, Polish Academy of Sciences, Twarda 51/55, 00-818 Warsaw, Poland.