By the end of the last century, the only region in all of Europe where the natural vegetation remained untouched over large expanses was Eastern Europe. Information on the vegetation of this region however, remained mostly unavailable to western scientists although the ecological approach to botanical research originated in Eastern Europe. Heinrich Walter was born in Russia, studied Natural Sciences - with emphasis on botany - in Odessa and is familiar with all relevant Russian literature on ecology. This volume thus offers scientists worldwide a unique and comprehensive survey of all relevant research, including the mostly unknown literature published in Russian.