Holocene paleoclimate inferred from stable isotope (δ18O and δ13C) values in Sphagnum cellulose, Mohos peat bog, Romania

Abstract

We measured stable isotopes (δ18O and δ13C) in Sphagnum cellulose that was extracted from a long peat core drilled in the ombrotrophic Mohos peat bog, Ciomadul Mountain, Romania. The 10-m-long peat profile spans the period from 11,800 cal yr BP to present. The δ18O and δ13C data indicate there were several cooling events and warm periods in the area of the Mohos peat bog during the Holocene. The 8.2-ka cold event, however, was not detected using δ18O and δ13C values. Response of the peat bog to changing environmental conditions was inferred using data on organic matter accumulation, independent of the stable isotope results. All cool periods during the Holocene, whether of short or long duration, were identified as times of reduced organic matter accumulation rate. Similarly, dry periods were also correlated with reduced accumulation rates of organic matter.

Holocene landscape evolution, palaeoclimate and human impact in the Fotsch Valley, Stubai Alps, Austria: Interrogating biomarkers, stable isotopes, macrofossils and palynological indicators from a subalpine mire archive

“…kyr BP) point to low evapo(transpi-)rative enrichment during the Roman Warm Period (Figure 8). This is in agreement with more humid climatic conditions with seasonal pluvial pulses as reported by Büntgen et al (2011) and Túri et al (2021). Moreover, decreasing n C 31 /( n C 27 + n C 31 ) and ACL ratios during the Roman Age can be associated with an increasing occurrence of mosses because of increasingly humid conditions on the FPM.…”

“…We therefore assume that the Mesolithic hunter-gatherers have changed their encampment sites with rising timberline and relocating subalpine vegetation zone towards higher altitudes in the Fotsch Valley. The ongoing Early Holocene climate amelioration culminating in the Holocene climatic optimum, that is, warm and humid climate from 8.7 to 7.4 kyr BP (Kalis et al, 2003; Túri et al, 2021), was accompanied by a fast timberline rise in the Alps (Pini et al, 2017) and likely caused the FPM to start growing. Respective timberline shifts are also discussed for the Fotsch Valley (Schäfer, 2011b).…”

“…From a methodological point of view, stable oxygen isotope (δ 18 O) records from mire archives can provide valuable palaeoclimatic insights (e.g. Túri et al, 2021).…”

Mid-Holocene Climate Record in Santovka Travertine (Slovakia) and regional Biases of Climate Shifts 8.2 and 7.4 ka BP

“…Similarly, an even more significant abrupt shift was detected in the δ 13 C records of Santovka-village (7304-7254 490 cal BP), Grotta di Ernesto (7402-7352 cal BP), Katerloch Cave (7580-7480 cal BP), Poleva Cave (7510-7410 cal BP) and Nova Grgosova Cave (7458-7408 cal BP), where a synchronous event was identified and discussed in a previous study (Surić et al, 2021). Palaeolimnological records and peat records from Carpathians do not indicate the occurrence of the 7.4 ka BP event (Túri et al, 2021;Feurdean et al, 2007;Magyari et al, 2014). Nevertheless, at Sfânta Ana in the Eastern Carpathians 495 (Romania) a long-term rise of humidity after 7.4 ka BP is indicated palynologically (Magyari et al, 2014).…”