Exposure matters: Forest dynamics reveal an early Holocene conifer refugium on a north facing slope in Central Europe

Abstract

Although several studies provide a broad overview of vegetation changes in the Carpathian Basin during the Holocene, stand-scale vegetation changes are lesser known because of the rarity of suitable sampling sites. In this study we investigated the sediment of a small closed-canopy site (Nagy-forrás forest hollow, 685 m a.s.l., 0.1 ha), located in the Mátra Mountains, on the north facing slope of Kékes (1014 m a.s.l.). We carried out detailed pollen, conifer stomata and plant macrofossil analyses, as well as radiocarbon dating to examine Late Glacial and Holocene dynamics of vegetation development. The site dates back to ca. 15,500 cal yr BP, when open boreal forests and wet tundra-like habitats occurred around the hollow. Closed forest cover developed around 14,600 cal yr BP, when a boreal European larch-Swiss stone pine ( Larix decidua-Pinus cembra) forest surrounded the hollow. This vegetation type remained stable up to 7700 cal yr BP. We observed a hiatus between 7700 and 2710 cal yr BP, followed by a beech ( Fagus sylvatica) dominated mixed temperate deciduous forest. Our results confirmed that the area was covered by a primary forest, as human influence was visible only from 175 cal yr BP. The relatively long lasting persistence of Pinus cembra in the Holocene at relatively low altitude was documented, which has never been found in Holocene sediments in the Pre-Carpathians before. We hypothesize that the north facing slope acted as a cold-stage refugium in the Early Holocene and could play the same role for the present-day beech forest that is threatened by recent climate change.

New chronology and extended palaeoenvironmental data to the 1975 loess profile of Madaras brickyard, South Hungary

“…2). Similar changes were noted in the regional pollen, phytolith and anthracological records (Willis et al, 2000;Haesaerts, 2002, 2011;Willis and Van Andel, 2004;Ravazzi, 2002;Bhagwat and Willis, 2008;Sümegi et al, 2013aSümegi et al, ,b, 2015Sümegi et al, , 2018Sümegi et al, , 2019Feurdean et al, 2013Feurdean et al, , 2014Magyari et al, 2014aMagyari et al, ,b, 2019Vincze et al, 2019;Pató et al, 2020). As a result of cooling towards the end of the glacial, various species-rich forest-steppe ecotones (boreal open parkland, parkland, boreal forest steppe) emerged, which differed in the ratio of arboreal/nonarboreal elements.…”

“…Comparison of the malacological results was challenging as some regional publications (Marković et al, 2018) mixed the concept of spatially and temporally well-delineated biogeographical and Quarternary malacological units manifested as ecoregion mosaics (Olson et al 2001;Giakoumi et al, 2013) with that of zones (Gauthier and Wiken, 2003). To trace common changes in the vegetation, results of our phytolith and malacological analyses were compared with those of regional (Willis et al, 1995(Willis et al, , 1997(Willis et al, , 1998(Willis et al, , 2000Sümegi et al, 2011Sümegi et al, , 2013bSümegi et al, , 2020b, western and central European pollen and anthracological investigations Rybníček, 1991, 2014;Willis et al, 2000;Haesaerts, 2002, 2011;Willis and Van Andel, 2004;Ravazzi, 2002;Bhagwat and Willis, 2008;Feurdean et al, 2013Feurdean et al, , 2014Magyari et al, 2014aMagyari et al, ,b, 2019Vincze et al 2019;Pató et al, 2020).…”

Holocene vegetation dynamics of the Eastern Mediterranean region: Old controversies addressed by a new analysis

“…This region has been identified as a glacial refugium for a number of coniferous and deciduous trees. High‐resolution pollen records and macrofossils have shown the occurrence of Pinus , Juniperus , Betula , Salix and Picea in lowland areas and the Romanian Carpathians prior to 14.7 ky (Feurdean et al., 2007, 2010; Pató et al., 2020; Tanţău et al., 2014). Plant genetic data also point to this region as a glacial refugium (Magri et al., 2006; Petit et al., 2003), while genetic evidence of canopy forest snails also supports the existence of temperate trees in the Carpathians during the Late Glacial (Juřičková et al., 2019).…”

Low Altitude Glacial Relicts in the Romanian Flora

“…Moreover, the choice of setting an arbitrary threshold (15 points) for the final evaluation score in order to delimit glacial relicts from the other evaluated species, does not necessarily invalidate the possible relict status of other taxa whose total score falls below that threshold. For example, Carex appropinquata (14 points) is considered a possible glacial relict in both the Western [19] and South-Eastern Carpathians [72], as macrofossils of the species uncovered in the Carpathian Region (Mátra Mountains, northern Hungary) date back to the beginning of the Bølling and Older Dryas Late Glacial Periods (14,615 until 7,050 BP) [66]. Menyanthes trifoliata (14 points), a common species in the Arctic, has macrofossils in all the stadials and interstadials of the Late Glacial from the Carpathians [8,26,34].…”