Data from: Holocene environmental change in Rotsee and its impact on sedimentary carbon storage

To assess the long-term impact of climate change and human influence on
lakes and their sedimentary carbon storage, paleo-environmental approaches
using well-dated lake sediment cores can be employed. Here, we reconstruct
carbon mass accumulation rates for organic and inorganic carbon since 13
ka BP in Rotsee, a perialpine lake near the Swiss Alps, using a 12m
sediment core. A multiproxy approach (XRF, carbon and nitrogen isotopes,
organic macromolecule chemical compositions, aDNA) was used to explore
changes in the lake system that affect sedimentary carbon storage. The
Early Holocene (11.8 to 7 cal ka BP) was characterized by a mixed
phytoplankton and watershed-derived provenance of organic matter, and the
deposition of inorganic and organic sedimentary carbon. Warming during the
Holocene Thermal Maximum (9.8 to 8.8 cal ka BP) increased sedimentary
carbon storage. In the mid-to-late Holocene (7 to 1 cal ka BP), the
sedimentary record indicates an increased influx of allochthonous,
vascular plant-derived organic matter, and low production or conservation
of phytoplankton-derived carbon. Organic carbon storage increased, while
inorganic carbon became negligible. Larger deforestation events,
potentially during Neolithic times (around 4 ka BP), but especially during
Roman times (2 ka BP), coincided with further increased organic carbon
MARs. Recent sediments, influenced by eutrophication in the last century,
show higher carbon accumulation rates compared to earlier Holocene
periods. Rotsee serves as a case study of how climate warming and human
land use changes have influenced lake development and sedimentary carbon
storage, with broader implications for understanding carbon dynamics in
high-altitude lakes and their future carbon balance.