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We present a case study of the development of Sacrower See, a stratified, eutrophic lake in northeastern Germany, over the past 13,000 years. Total epilimnetic phosphorus (TP) concentrations were reconstructed quantitatively using a diatom-TP transfer function. Fossil chironomid assemblages were used to support the trophic reconstruction and helped assessing past hypolimnetic oxygen availability. The results indicate eutrophic and anoxic conditions during the Younger Dryas cold period (~12,700-11,600 cal. BP) preceding the present interglacial. Throughout the early and mid-Holocene (~11,600-4000 cal. BP) stable oligo- to mesotrophic conditions with diatom-inferred TP values of ~20 μg L-1 prevailed. First evidence of increasing Holocene TP is recorded at ~3500 cal. BP associated with Bronze Age human impact and for the past 900 years diatoms indicate increasing TP values of 30-60 μg L-1. During the early Holocene and the past two millennia chironomids indicated anoxic hypolimnetic conditions. The chironomid fauna is considered typical of oligo- to mesotrophic lakes. As a consequence of strongly increased primary production the hypolimnion of Sacrower See became anoxic again during the past 140 years. Our results indicate that highly productive eutrophic conditions can exist prior to cultural eutrophication. At Sacrower See the shift from eutrophic conditions in the Lateglacial to oligo-mesotrophic conditions in the early and mid-Holocene was associated with the climatic warming at the Younger Dryas/Holocene transition. The high productive state during the cold Younger Dryas is associated with changes in seasonality: the prolonged winters caused longer ice cover, stronger stratification, anoxia in the hypolimnion, and consequent internal phosphorus loading. During the warm Holocene, however, hypolimnetic anoxia and internal phosphorus loading decreased significantly, resulting in a substantially lower productivity. KIRILOVA, Emiliya, Oliver HEIRI, Dirk ENTERS, Holger CREMER, André F. LOTTER, Bernd ZOLITSCHKA, and Thomas HÜBENER. 2009. “Climate-Induced Changes in the Trophic Status of a Central European Lake”. Journal of Limnology 68 (1):71-82. https://doi.org/10.4081/jlimnol.2009.71. More Citation Formats ACM ACS APA ABNT Chicago Harvard MLA Turabian Vancouver Download Citation Endnote/Zotero/Mendeley (RIS) BibTeX Downloads Download data is not yet available. Citations Similar Articles Piero Guilizzoni, Suzanne N. Levine, Marina Manca, Aldo Marchetto, Andrea Lami, Walter Ambrosetti, Achim Brauer, Stefano Gerli, Elisabetta A. Carrara, Angelo Rolla, Licia Guzzella, Davide A.L. Vignati, Ecological effects of multiple stressors on a deep lake (Lago Maggiore, Italy) integrating neo and palaeolimnological approaches , Journal of Limnology: Vol. 71 No. 1 (2012) Walter Finsinger, Thierry Fonville, Emiliya Kirilova, Andrea Lami, Piero Guilizzoni, André F. Lotter, A long-term multi-proxy record of varved sediments highlights climate-induced mixing-regime shift in a large hard-water lake ~5000 years ago , Journal of Limnology: Vol. 73 No. 2 (2014) Marco Milardi, Jyrki Lappalainen, Suzanne McGowan, Jan Weckström, Can fish introductions alter nutrient cycles in previously fishless high-latitude lakes? , Journal of Limnology: Vol. 76 No. 1 (2017) Enlou Zhang, Yanmin Cao, Peter Langdon, Qian Wang, Ji Shen, Xiangdong Yang, Within-lake variability of subfossil chironomid assemblage in a large, deep subtropical lake (Lugu lake, southwest China) , Journal of Limnology: Vol. 72 No. 1 (2013)

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