Climatic moisture conditions in the north-west of the Mid-Russian Upland during the Holocene

Abstract

This study aimed to reconstruct the climatic moisture conditions of the Mid- Russian Upland through the Holocene. Surface moisture conditions in the study region were inferred from published pollen records from the Klukva peatland, in the north-west of the Mid-Russian Upland. Three climatic indices were derived from previously- published reconstructions of mean annual temperature and precipitation: the Climate Moisture Index, the Aridity Index and the Budyko Dryness Index. A simple modeling approach to reconstruct annual potential evapotranspiration and net radiation was developed and used to estimate the indices for different periods of the Holocene. The moisture indices were compared with independent proxies of climate moisture such as peatland surface wetness, reconstructed from testate amoebae and regional fire activity, reconstructed from charcoal. Results show that the surface moisture conditions in the study region were characterized by large variability. Periods of mild temperature and moderately wet conditions were followed by dry periods, which resulted in significant changes in palaeoenvironments. The method developed for calculation of potential evapotranspiration and indices of surface moisture conditions could be a useful tool for climate reconstructions. Our results demonstrate the detailed and nuanced palaeoclimate data which can be derived from pollen data.

The Holocene paleoenvironmental history of Western Caucasus (Russia) reconstructed by multi-proxy analysis of the continuous sediment sequence from Lake Khuko

“…The LOI 550°C curve shows a peak at 3.0 ka BP, marking the abundance of organic material probably related to warmer conditions. A warm and dry phase with high fire activity was detected between 3.7 and 2.7 ka BP in the East European Plain (Novenko et al, 2019). Lake Luganskoye (B. Laba valley, Western Caucasus) was transformed into a peatland between 3.2 and 2.8 14 C kyr BP (3.4–2.9 ka BP) potentially due to the warming of climate and decrease of humidity (Davydova, 1995).…”

A New Climate Nowcasting Tool Based on Paleoclimatic Data

“…The dataset used in the present analysis contains parameters that reflect the long-term dynamics of surface wetness and peat humification in two peat bogs situated in the East European Plain (namely Klukva [15,16] and Staroselsky Mokh [17]) during the Holocene. Due to the fact that peat bogs receiving water only from the atmospheric via precipitation, surface wetness can be a very good indicator to reflect surface moisture conditions.…”

“…To describe the surface wetness, we used in our study three key parameters: (i) the water table depth (WTD) in relation to the surface (i.e., the depth of water below the bog surface), which was reconstructed based on the community structure of the subfossil testate amoeba assemblages, using the transfer function developed by Tsyganov et al [20]; (ii) the peat humification estimated as absorption of alkaline extract that directly reflects the moisture in which the peat was formed [21]; (iii) the Climate Moisture Index (CMI) suggested by Willmott and Feddema [22] and the Aridity Index obtained using pollen-based reconstructions of the mean annual temperature and precipitation which allows the classification of moisture conditions as the ratio between available annual precipitation and potential land surface evapotranspiration [15,23].…”

“…Recently, we applied biological (remains of pollen and testate amoebae in peat) and physicochemical (peat humification) proxies to reconstruct surface wetness dynamics during the Holocene in two peatlands in the East European Plain [15][16][17].…”

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

“…Changes in bog surface wetness can be reconstructed using a range of techniques, including the composition of the peat-forming vegetation [13,14], the degree of peat decay (more decomposed peat is generally formed under dry conditions) [15] and testate amoeba analysis (various taxa prefer dry or wet substrates) [16,17]. Many pollen-based methods are used to reconstruct long-term temperature and climatic moisture variability at regional and global scales [18,19]. Pollen and spores also reflect wider regional vegetation changes, which can, in turn, be closely linked to archaeological evidence for human activity and cultural change [20], alongside microscopic and macroscopic charcoal relating to both on and off-site fire histories [21].…”