Reconstruction of palaeoenvironmental variability based on an inter-comparison of four lacustrine archives on the Peloponnese (Greece) for the last 5000 years

Abstract

Abstract. A high quantity of well-dated, high-resolution, continuous geoarchives is needed to connect palaeoenvironmental reconstructions with socio-environmental and cultural transformations in a geographically heterogeneous region such as southern Greece. However, detailed and continuous palaeoclimatic and palaeoenvironmental archives from the NE Peloponnese are still sparse. Here, we present two new palaeolake archives of Pheneos and Kaisari covering the last 10 500 and 6500 years, respectively. For the last 5000 years, we compare them with sediment records from adjacent Lake Stymphalia and the Asea valley by applying the same set of sedimentological, geochemical, and statistical analyses to all four lacustrine archives. Continuous geochemical X-ray fluorescence (XRF) core scanning records provide evidence for hydrological variations and environmental changes since the Early Helladic period (5050 BP), the beginning of the Bronze Age in Greece. We hereby focus on different spatial scales to estimate the validity range of the proxy signals. Ten elements were selected (Al, Si, K, Ca, Ti, Mn, Fe, Rb, Sr, Zr) for a principal component analysis. The clr(Ca∕Ti) was chosen as the most meaningful proxy, reflecting varying input of carbonaceous vs. clastic input, which may be linked to changes in the hydrological conditions. Our results show phases when permanent lake water bodies existed (ca. 5000–3600 cal BP) as well as phases with periodic desiccation of the lakes during younger times. While Pheneos and Kaisari show a drying trend during the transition phase from the Late Helladic period to the Proto-Geometric period (ca. 3200–2800 cal BP), Stymphalia and Asea show a rather short dry peak around 3200 cal BP followed by a wetter phase. Although all our geoarchives show evidence for drier phases, their timing and duration display considerable site-to-site differences which may be explained by site-specific responses in individual ecosystems. Age uncertainties, however, may likewise explain some deviations, as the dating is based on bulk sediment samples including potential unknown reservoir effects. The high regional geographical diversity within the Peloponnese combined with the dating challenges in the limestone-rich area and the variation in our data testify that any hypothetical mono-causal connection between palaeoenvironmental changes in a single geoarchive and contemporaneous societal transformations across the Peloponnese would be an oversimplification.

Late-Holocene paleoenvironmental and land-use changes in Western Greece based on a sediment record from Klisova lagoon

“…Kouli et al, 2012; Panagiotopoulos et al, 2014; Tzedakis et al, 2002; Wijmstra, 1969), sediment element composition detecting catchment processes (e.g. Bassukas et al, 2021; Francke et al, 2019; Seguin et al, 2020), and stable isotopes recording hydroclimatic variations (e.g. Finné et al, 2017; Roberts et al, 2008).…”

Holocene Hydroclimatic Changes in Northern Peloponnese (Greece) Inferred from the Multiproxy Record of Lake Lousoi

“…Lacustrine records studied so far in northern Peloponnese (Stymphalia, Kesari, Pheneos, and Asea) represent shallow water bodies that have experienced long periods of desiccation and are highly influenced by climatic/environmental forcing, anthropogenic activity, and pedogenic processes [5,8,22]. To summarize the geochemical composition from the prior mentioned sedimentary sequences, previous studies have used principal component analysis, with PC1 explaining the inflow of carbonate-rich clastic material during periods of increased weathering in the catchment, whereas PC2 explains the enhanced carbonate precipitation during dry-warm conditions [8]. We applied the same method here for these sites, but for Lake Lousoi, the resolution of our geochemical data did not permit a robust analysis; thus, we interpreted each geochemical proxy separately (Figure 7).…”

“…Same signals with increased detrital inflow were recorded for Lakes Lousoi, Pheneos, and Kaisari, especially from 6700 to 5800 cal BP, where the highest concentration of detrital elements and MS are recorded (Figures 4 and 6). At Lake Pheneos, south of Lake Lousoi, the system seems to be a permanent water body from 5000 to 3600 cal BP, due to wet climatic conditions and perpetual supply of fresh water [8]. More to the south, the Asea valley's record presents stable conditions and lack of lake sediments from 5000 to 3400 cal BP, with some minor dry trends recorded at 4900 and 4700 cal BP [22].…”

“…In this study, we present a new sedimentological archive from Lake Lousoi, located in the central part of Peloponnese (Figure 1b). The lake presents similar geomorphological and environmental characteristics to Stymphalia and Kaisari poljes [5,8], allowing a reliable and robust investigation and better evaluation of similar/opposing signals. Archaeological evidence in the area indicates that the region was inhabited at least from the Middle Neolithic (5700-5300 BCE) [9].…”

A Holocene Sedimentary Record and the Impact of Sea-Level Rise in the Karst Lake Velo Blato and the Wetlands on Pag Island (Croatia)

“…Lake sediments from these lakes provide records of Holocene paleoenvironmental changes containing a combination of natural hydrological to climatic and anthropogenic signals, in relation to sea level rise and local catchmentspecific processes. In the central and eastern Mediterranean, a wetter climate prevailed in early to mid-Holocene [28][29][30][31], followed by the drier climate conditions during the mid-Holocene, and several arid phases, with considerable site-to-site differences [2,[31][32][33]. In the Adriatic Sea marine sediment core records, the wet early to mid-Holocene was determined [34,35], supported by the lake and marine sediment cores in the eastern Adriatic Sea [10,14,15,18,23,26,27,36,37].…”