The impact of Lusatian Urnfield and subsequent prehistoric cultures on lake and woodland ecosystems: insights from multi-proxy palaeoecological investigations at Bruszczewo, western Poland

The Lusatian Urnfield culture (LUc, Lausitzer Kultur, kultura łużycka) was one of the most important cultural developments during the Late Bronze and Early Iron Age of central-eastern Europe, 1500–500 bc. In this article, we focus on the impact of the LUc and later cultures on the terrestrial and aquatic ecosystems at Bruszczewo on a microregional scale and within the broad context of analogous processes in central-eastern Europe. We did high resolution multi-proxy analyses of pollen, non-pollen palynomorphs (NPPs), diatoms and plant macrofossils, supplemented with a lithological and geochemical study of lake and peat deposits from near the archaeological site. The results revealed that between ca. 1020 and 920 bc, woodland clearance took place, possibly connected with farming. This probably contributed to the spread of the weeds Xanthium cf. strumarium and Convolvulus arvensis in the newly created disturbed habitats. Woodland clearance and other human activities contributed to better preservation of diatoms in the lake sediments, probably as a result of increased acidity in this environment. Diatoms, especially taxa preferring eutrophic waters and tolerant of large amounts of dissolved organic matter, were the most frequent at that time. Climate deterioration associated with the 2.8 ka event probably lessened human impact around the lake shore. The diatom records suggest prolonged ice cover on the lake and/or colder springs at that time. Another intensification of human impact occurred at ca. 530 bc and was probably related to activity by people of Pomeranian culture (kultura pomorska, Pommerellische Gesichtsurnenkultur). Later, from ca. 330 bc, arable farming activity declined and grazing was suggested by an abundance of coprophilous fungi spores which, however, should not be regarded as definitive indicators of pasture.