Long-term human-environmental interactions in naturally fragile drylands are a
focus of geomorphological and geoarchaeological research. Furthermore,
many dryland societies were also affected by seismic activity. The semi-arid
Shiraki Plain in the tectonically active southeastern Caucasus is currently
covered by steppe and largely devoid of settlements. However, numerous
Late Bronze to Early Iron Age city-type settlements suggest early state
formation between ca. 3.2-2.5 ka that abruptly ended after that time. A
paleolake was postulated for the lowest plain, and nearby pollen records
suggest forest clearcutting of the upper altitudes under a more humid
climate during the Late Bronze/Early Iron Ages. Furthermore, also an impact
of earthquakes on regional Early Iron Age settlements was suggested. However,
regional paleoenvironmental changes and paleoseismicity were not
systematically studied so far. We combined geomorphological,
sedimentological, chronological and paleoecological data with hydrological
modelling to reconstruct regional Holocene paleoenvironmental changes, to
identify natural and human causes and to study possible seismic events during
the Late Bronze/Early Iron Ages. Our results show a balanced to negative Early
to Mid-Holocene water balance probably caused by forested upper slopes.
Hence, no lake but a pellic Vertisol developed in the lowest plain. Following,
Late Bronze/Early Iron Age forest clear-cutting caused lake formation and the
deposition of lacustrine sediments derived from soil erosion. Subsequently,
regional aridification caused slow lake desiccation. Remains of freshwater fishes
indicate that the lake potentially offered valuable ecosystem services for
regional prehistoric societies even during the desiccation period. Finally,
colluvial coverage of the lake sediments during the last centuries could have
been linked with hydrological extremes during the Little Ice Age. Our study
demonstrates that the Holocene hydrological balance of the Shiraki Plain was
and is situated near a major hydrological threshold, making the landscape very
sensitive to small-scale human or natural influences with severe consequences
for local societies. Furthermore, seismites in the studied sediments do not
indicate an influence of earthquakes on the main and late phases of Late
Bronze/Early Iron Age settlement. Altogether, our study underlines the high
value of multi-disciplinary approaches to investigate human-environmental
interactions and paleoseismicity in drylands on millennial to centennial time
scales.
| Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa:de:qucosa:88253 |
| Date | 24 November 2023 |
| Creators | von Suchodoletz, Hans, Kirkitadze, Giorgi, Koff, Tiiu, Fischer, Markus L., Poch, Rosa M., Khosravichenar, Azra, Schneider, Birgit, Glaser, Bruno, Lindauer, Susanne, Hoth, Silvan, Skokan, Anna, Navrozashvili, Levan, Lobjanidze, Mikheil, Akhalaia, Mate, Losaberidze, Levan, Elashvili, Mikheil |
| Publisher | Frontiers Media S.A. |
| Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
| Language | English |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, doc-type:article, info:eu-repo/semantics/article, doc-type:Text |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | 10.3389/feart.2022.964188 |
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