Forest history, peatland development and mid- to late Holocene environmental change in the southern taiga forest of central European Russia

Abstract

Understanding the long-term ecological dynamics of boreal forests is essential for assessment of the possible responses and feedbacks of forest ecosystems to climate change. New data on past forest dynamics and peatland development were obtained from a peat sequence in the southern Valdai Hills (European Russia) based on pollen, plant macrofossil, micro-charcoal, peat humification, and testate amoeba analyses. The results demonstrate a dominance of broadleaved forests in the study area from 7000–4000 cal yr BP. Picea was initially a minor component of this forest but increased in cover rapidly with climatic cooling beginning at 4000 cal yr BP, becoming the dominant species. Broadleaved species persisted until 900 cal yr BP, with evidence for intensified felling and forest management over recent centuries. Over the last four hundred years there is evidence for widespread paludification and the establishment of Picea-Sphagnum forests. These data demonstrate how modern wet woodlands have been shaped by a combination of climatic and anthropogenic factors over several millennia. The results also demonstrate the value of a multiproxy approach in understanding long-term forest ecology.

Peatland Development, Vegetation History, Climate Change and Human Activity in the Valdai Uplands (Central European Russia) during the Holocene: A Multi-Proxy Palaeoecological Study

“…Besides, our pollen record suggests the rise of herbaceous plants, such as Artemisia and Plantago (Figure 5), that may be related to cooling and indicate human impact and development of arable land [34]. Indirect support of possible human influence on a local scale provides evidence of stable spruce abundance in the southern part of the Valdai Uplands [69]. The decreased proportion of broadleaved trees coincides with an increased concentration of macro charcoal.…”

“…However, the proportion of broadleaved trees in forests remained relatively high in central European Russia, Belarus and the Baltic region during 3700-2000 BC [72,80,81]. The proportion of Picea in the pollen spectra also increased in the Krivetskiy Moch ( Figure 5) as well as in other studied areas of the southern part of the Valdai Uplands [69]. Probably it was correlated with the low frequency of forest fires [67].…”

“…In the Late Atlantic (5500-3700 BC), the study region was covered by the vegetation by various types of broadleaved and mixed coniferous-broadleaved forests [34]. Forests composed of Betula, Alnus, Quercus, Ulmus and Corylus with rare Picea and Pinus ( Figure 5), which grew on mires and water-logged sites around them [69]. These observations are in agreement with previous works that suggest that the Atlantic stage was characterized by maximal heat supply and optimal temperature and precipitation conditions over the entire territory of Northern Eurasia [69].…”

“…Forests composed of Betula, Alnus, Quercus, Ulmus and Corylus with rare Picea and Pinus ( Figure 5), which grew on mires and water-logged sites around them [69]. These observations are in agreement with previous works that suggest that the Atlantic stage was characterized by maximal heat supply and optimal temperature and precipitation conditions over the entire territory of Northern Eurasia [69]. Among non-arboreal pollen, Artemisia, Chenopodiaceae, Brassicaceae, Rosaceae and Poaceae were occasionally abundant (Figure 4) that might reflect possible human impact.…”

“…At the beginning of the Subatlantic stage, the spruce forest became the main vegetation type in the Eastern Europe Plain [32,76,[80][81][82]. After 600 BC, coniferous forests spread from the Valdai Uplands and the northeastern part of European Russia to the central regions [69]. Besides, our pollen record suggests the rise of herbaceous plants, such as Artemisia and Plantago (Figure 5), that may be related to cooling and indicate human impact and development of arable land [34].…”