Tiliaforest dynamics,Kretzschmaria deustaattack, and mire hydrology as palaeoecological proxies for mid-Holocene climate reconstruction in the Kashubian Lake District (N Poland)

Abstract

Pollen, non-pollen palynomorph, macrofossil, and lithological analyses of mid-Holocene deposits from a small peat bog in northern Poland provide new proxy data on vegetation dynamics and climate between c. 9500 and 4600 cal. BP. The most prominent wetter climate phases occurred between c. 9500 and 9280±160 and between c. 5000 and 4600 cal. BP while a hot and dry period between 8185±145 and 5299±195 cal. BP corresponds with the Holocene Thermal Maximum (HTM). The HTM phase has been characterized by absolute dominance of Tilia cordata and the presence of T. platyphyllos beyond its current geographical range limit and a c. 2700 yr long, high incidence of the parasite fungus Kretzschmaria deusta in the local forest stand, concurrent with a dry phase on the mire. For the HTM, we suggest mean summer temperatures at least 3°C higher than today’s values. These data are in accordance with the geographic pattern of the HTM temperature anomalies in northern Europe, including the Baltic region, which suggest a gradient of positive anomalies from north to south and from west to east. The data also illustrate the effect of climate warming on the mid-Holocene pathogen outbreak and may indicate intensive vegetative reproduction as a Tilia strategy for population survival. Summer drought was probably important for high success of K. deusta in infecting weakened Tilia trees.

A Review of the Characteristics of Small-Leaved Lime (Tilia cordata Mill.) and Their Implications for Silviculture in a Changing Climate

“…Pollen analyses show that, from the beginning of the post-glacial period until the mid-Holocene, T. cordata was a major tree species of the European woodland [11,107]. During the Holocene Thermal Maximum, which was a very hot and dry period with summer temperatures at least 3˝C warmer than they are now (between approximately 8200 and 5300 B.P.…”

“…During the Holocene Thermal Maximum, which was a very hot and dry period with summer temperatures at least 3˝C warmer than they are now (between approximately 8200 and 5300 B.P. ), its dominance was nearly absolute in eastern Europe [107]. T. cordata maintained its co-dominance for 2000 years, and then declined considerably between 4000 and 2400 B.P., depending on the region [11], as a result of both climate cooling, favorable to other species (e.g., P. abies, F. sylvatica) and growing human activities.…”

Mycological and palynological studies of early medieval cultural layers from strongholds in Pszczew and Santok (western Poland)

“…(type 55C), points to local peat bog fires. Fungal infection might also cause changes in the dynamics of tree appearance, which is demonstrated in the decrease of the tree stands with linden as a result of infestation of Kretzschmaria deusta (Ustulina deusta) in the Middle Holocene in the area of Gołębiewo [10].…”

“…Particularly intense development of the interest into the palaeomycological matters can be dated back to the second half of the 20th century [6][7][8][9]. Multidisciplinary research combining palynological and mycological analyses has been also carried out in Poland [2,10]. In this respect, the interdisciplinary mycological and palynological research not only completes the reconstruction of the palaeoenvironment, but it can also constitute an additional element pointing to, among other things, the hazards to the health of the plants from phytopathogenic fungi and the resulting consequences for the societies.…”

Anthropogenic Transformation of the Vegetation in the Immediate Vicinity of the Settlement Complex at Poganowo (Mrągowo Lakeland, Ne Poland)

“…Birks, 2003;Lata³owa et al, 2013). Among the microfossils that are ob served in pol len slides, fungi, al gae and other non-pol len palynomorphs (NPP) have be come partic u larly im por tant, be cause of their po ten tial to im prove recon struc tion of past eco sys tems (van Geel, 2001;van der Lin den et al, 2012).…”