Environmental Change Reconstruction Laboratory

...all that happens today is the product of what happened yesterday.


A new paper summarizing our decade-long (2012–2019) observations of modern processes in Lake Żabińskie has just been published in STOTEN. The major goal was to understand varve formation processes in this lake, in particular to find the records of meteorological signals in varves. We compared meteorological data, physicochemical water parameters, and modern sedimentation measurements with a high-resolution biogeochemical proxy dataset based on μXRF and hyperspectral imaging (HSI) of a varved sediment core spanning the same period. We found interesting relationships between air temperature and calcite laminae formation, lake mixing intensity and calcite grain size, and between holomixis events and the deposition of manganese (Mn) in the anoxic sediments. Happy reading!

Żarczyński M., Zander P., Grosjean M., Tylmann W. 2022. Linking the formation of varves in a eutrophic temperate lake to meteorological conditions and water column dynamics. Science of the Total Environment, 842, 156787. DOI 10.1016/j.scitotenv.2022.156787. LINK


On May 23-27 The EGU General Assembly 2022 was held in Vienna. Among more than 7,000 participants onsite, ECRLab was represented by Alicja Bonk, Agnieszka Szczerba and Wojciech Tylmann. We delivered two presentations related to our ongoing research:

Alicja Bonk, Claire Belcher, Wojciech Tylmann – Is charcoal reflectance a palaeofire intensity proxy?

Agnieszka Szczerba, Sergi Pla-Rabes, Maurycy Żarczyński, and Wojciech Tylmann – Chrysophyte cysts reflect seasonal meteorological and limnological conditions: Evidence from sediment trap study in northeast Poland.

Besides, we had a good time in beautiful Vienna!


On May 16-20 an online conference PAGES 6th Open Science Meeting was held in Agadir. The main topic of the meeting was „Learning from the past for a sustainable future”. Ala Bonk from our lab presented ePoster about her ongoing research entitled: “Ecological responses to environmental changes revealed from a varved sequence of Lake Lubińskie (western Poland)”. Additionally, Paul Zander (University of Bern) provided a talk “Holocene spring and summer temperature variability inferred from Ca/Ti ratios, Lake Żabińskie, Poland” presenting our joint research results from northern Poland.


In the frame of the National Science Centre project „Eutrophication, mixing regime changes and anoxia: tracking the responses of varved Lake Gorzyńskie (NW Poland) to climate variability and human impact during the Holocene” we visited the Geopolar Lab at the University of Bremen (28-30.03.2020). The goal of our visit was to open and correlate sediment cores from Lake Gorzyńskie. The sediment cores were also scanned with XRF Itrax Core Scanner to get the information about chemical composition of the sediments.


Conference “Fire impacts at the Earth surface across space and time: perspectives for future fire management” took place in Bad Belzig (Germany) between 28th of March and 1st of April. The conference aimed to provide a discussion-driven meeting to facilitate knowledge transfer between fire science disciplines and to identify research needs to support fire management of the future.

Ala Bonk presented a short talk followed by poster presentation:
Alicja Bonk, Michał Słowiński, Maurycy Żarczyński, Piotr Oliński, Mirosława Kupryjanowicz, Magdalena Fiłoc, Wojciech Tylmann
Human activity as the main driver of forest fires in northeast Poland over the last 1,750 years

Photo credits Michael Foerster


On March 21-22 Paleolimnology Session was held at the Institute of Physics, Silesian University of Technology in Gliwice. This year, the main topic focused on multiproxy paleoreconstructions. Our lab presented two oral presentation and two posters about ongoing research in northern Poland.

Oral presentations:
Alicja Bonk, Michał Słowiński, Maurycy Żarczyński, Piotr Oliński, Mirosława Kupryjanowicz, Magdalena Fiłoc, Wojciech Tylmann
History of wildfires in northeastern Poland and their impact on Lake Jaczno

Natalia Piotrowska, Alicja Bonk, Wojciech Tylmann, Maurycy Żarczyński, Dirk Enters
Chronology of the Lake Lubińskie sediment record

Maria Kril, Krzysztof Pleskot, Karina Apolinarska, Aleksandra Pełechata, Małgorzata Szymczak-Żyła, Piotr Kołaczek, Monika Rzodkiewicz, Izabela Zawiska, Wojciech Tylmann
Changes in eutrophication and mixing regime of Lake Gorzyńskie (NW Poland) during the Holocene: new research project

Agnieszka Szczerba, Monika Rzodkiewicz, Wojciech Tylmann
Is the weather important for diatoms? Short-term conditions of diatom communities variability in lakes Łazduny and Rzęśniki


A new paper published in Water presents the challenges of interpreting geochemical data obtained from different analytical techniques (XRF-CS and FPXRF scanning, and ICP-OES), which were used to assess the environmental changes of karst sediments (Lake Ighiel, Romania). The comparison between techniques was based on a set of elements that are widely employed in environmental reconstructions of lake sediments (Ti, K, Fe, Ca). The research shows a number of discrepancies between the approaches used, indicating that a combination of quantitative and qualitative geochemical methods would be the most appropriate approach to reliable data acquisition and palaeoenvironmental interpretation of lake sediments.

Haliuc A., Bonk A., Longman J., Hutchinson S.M., Zak M., Veres D. 2022. Challenges in Interpreting Geochemical Data: An Appraisal of Analytical Techniques Applied to a Karstic Lake Sediment Record. Water, 14 (5), 806. DOI 10.3390/w14050806. LINK


New research on the interplay between changing climatic conditions, land cover transformation, fires, and human activity has just been published in The Holocene. The study led by Ala Bonk is based on the 1750-year-long macrocharcoal record derived from varved sediments of Lake Jaczno in northeast Poland. Macrocharcoal morphotypes, pollen and historical data, and statistical analysis revealed that most of low- and high-intensity fires that occurred in the vicinity of the lake were set by humans, but in some periods biomass burning was favored by droughts or other natural causes. Human-induced fires are especially evident between AD 1081 and 1283 which corresponds to the peak activity of the Jatvings tribe in the region and the related deforestation for agrarian purposes. Happy reading!

Bonk A., Słowiński M., Żarczyński M., Oliński P., Kupryjanowicz M., Fiłoc M., Tylmann W., 2022. Tracking fire activity and post-fire limnological responses using the varved sedimentary sequence of Lake Jaczno, Poland. The Holocene. DOI:10.1177/09596836221080755. LINK


Last week, the Single Core Scanner (Specim, Finland) has been installed at our lab. The SCS is a non-destructive hyperspectral scanner designed for studying sediment cores. Our SCS is equipped with a VNIR (400-1000 nm) camera and will be used for detecting organic compounds in lake and marine sediment cores. This method is cost- and time-efficient, and provides insight into the spatiotemporal structures of bio-geochemical species at a very high degree of detail. This is significant step forward in the development of our lab.

After unpacking the equipment, it turned out that using the scanner box we can start training bobsleigh!


National Science Centre project led by Alicja Bonk: „ Investigating fire history in Poland over the last 2000 years using annually laminated lake sediments” (2019/32/C/ST10/ 00038) allowed her to complete a research internship at wildFIRE Lab at the University of Exeter, the UK (1.09-31.12.2021). During her stay, Alicja measured the reflectance of charcoals found in the sediments of two Polish lakes, Lubińskie and Żabińskie, located in western and north-eastern Poland, respectively. The results of this research will yield to extend the knowledge about the vegetation fires intensity in the past.


Polish National Agency For Academic Exchange (NAWA) has just published a list of the Bekker Programme edition 2021. The Bekker Programme aims at the international collaboration of Polish scientists. Maurycy Żarczyński with his project “Reconstruction of environmental change during glacial-interglacial cycles of the last 1.3 million years recorded in the Stoneman Lake sediments (Arizona, USA): a novel perspective from hyperspectral imaging” has been awarded an 18-month stay at the Northern Arizona University in Flagstaff, USA. During his stay Maurycy will join the research group of Professor Darrell Kaufman. Congratulations!


As Christmas is fast approaching we celebrated this last moment at work with our friends. That was not a standard Christmas dinner but rather “pizza & beer” party… Anyway, we had a great time being together. See all of you next year!


New paper related to our ongoing monitoring of Masurian lakes has just been published in Ecological Indicators. The study led by Agnieszka Szczerba explores the potential of chrysophyte cysts as indicators of seasonal and interannual changes in meteorological conditions in lakes. High-resolution monitoring of lakes Łazduny and Rzęśniki using sediment traps, limnological and hydrochemical measurements, and meteorological data allowed us to show that cyst seasonality indirectly corresponds to meteorological conditions acting through changes in the mixing regimes, which in turn influences nutrient and light availability. The work was done in cooperation with Sergi Pla Rabés from CREAF, Barcelona. Happy reading!

Szczerba A., Pla-Rabes S., Żarczyński M., Tylmann W., 2021. The relationship between chrysophyte cyst assemblages and meteorological conditions: Evidence from a sediment-trap study in northeast Poland. Ecological Indicators, 133: 108395. DOI 10.1016/j.ecolind.2021.108395. LINK


Guillermo de Mendoza took part in a CenTrain500 Workshop (Central Eastern and Northern Europe Training Set Development for last 500-year Quantitative Environmental and Climate Reconstruction) which was held in Budapest, November 11-13, 2021. The meeting was organized by ELTE (Eötvös Loránd University, Hungary), the Institute of Aquatic Ecology (Budapest, Hungary), and the Department of Water Supply and Sewerage (University of Public Service, Hungary). Guillermo gave oral presentation “Exploring the influence of continentality on the distribution of lake chironomids in northern Poland: potential implications for paleotemperature reconstructions”.


In the new paper published in Anthropocene we present sediment records form three lakes (Dubie, Salno and Wasoskie) located in northern Poland. Topmost sediments of these lakes document that the onset of varve formation and preservation was related to human-induced changes in the catchments. Thanks to reliable dating, analyses of sediment structure and composition, and documentary sources we were able to recognize the timing of verve formation and the processes responsible. This study shows that well preserved varves in the topmost sediments of many lakes are geological evidence of human activity. Happy reading!

Poraj-Górska A.I., Bonk A., Żarczyński M., Kinder M., Tylmann W., 2021. Varved lake sediments as indicators of recent cultural eutrophication and hypolimnetic hypoxia in lakes. Anthropocene, 36: 100311. DOI 10.1016/j.ancene.2021.100311. LINK