Publication Details |
| Category | Data Publication |
| DOI | 10.5281/zenodo.15496088 |
| Licence |
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| Title (Primary) | Sediment records of lake Chaohu, China [Dataset] |
| Author | Kong, X.; He, Q.; He, W.; Qin, N.; Xu, F. |
| Source Titel | Zenodo |
| Year | 2026 |
| Department | SEEFO |
| Language | englisch |
| Topic | T5 Future Landscapes |
| Abstract | Eutrophication-driven algal blooms pose a persistent threat to freshwater ecosystems globally, and their role in regulating the environmental fate of hydrophobic hazardous pollutants such as polycyclic aromatic hydrocarbons (PAHs) remains poorly understood due to the lack of long-term causal evidence and quantitative mechanistic insights. Here, we integrated 144-year sediment biomarker records in Lake Chaohu, China, with a novel framework combining causality analysis and a mechanistic model (EUTOX) that couples algal physiological processes with a multimedia fugacity approach. For the first time, this framework enables quantitative evaluation of the algal “biological pump” effect on PAH transport and sequestration. Our results demonstrate that, at the decadal scale, algal-derived organic matter is the dominant driver of PAH accumulation in lake sediments, with a significant increase in PAH sequestration coinciding with the intensification of algal blooms. At the seasonal scale, the EUTOX model quantified the dominance of phytoplankton absorption in PAH accumulation in suspended solids (90.9%), which drove net sediment deposition of 12.82, 6.45, and 1.19 t/yr for Phe, Pyr, and BaP, respectively. Summer blooms enhanced sedimentation while inducing a biomass-driven dilution effect on PAH concentrations in phytoplankton. Algal uptake reduces dissolved PAH concentrations and disrupts air–water equilibrium, thereby enhancing atmospheric deposition and increasing atmosphere-to-water fluxes by 151% (4.2–842.9%). Furthermore, high-molecular-weight PAHs (e.g., BaP, up to 98.4%) preferentially partition into the algal matrix, which significantly promotes their sedimentation and increases water-to-sediment fluxes by 98% (1.4–707%). These findings confirm that algal blooms act as an active biological pump governing the transport and sequestration of hydrophobic PAHs in eutrophic lakes. Our findings imply that lake eutrophication mitigation reduces biological pump-mediated sequestration of hydrophobic pollutants in lake sediments and associated food web exposure risks. |
| linked UFZ text publications | |
| Kong, X., He, Q., He, W., Qin, N., Xu, F. (2026): Sediment records of lake Chaohu, China [Dataset] Zenodo 10.5281/zenodo.15496088 |
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