Chironomid and aquatic invertebrate assemblages and deepwater oxygen availability during the Lateglacial and Holocene in a small Swiss lowland lake (Bichelsee, Switzerland)
Data files
Jan 29, 2026 version files 503.46 KB
-
R_code_for_CCAs.txt
1.28 KB
-
README.md
3.12 KB
-
Supplementary_Data_Publication.xlsx
492.18 KB
-
Supplementary_Table_1.csv
6.89 KB
Abstract
The data herein presents chironomid and aquatic invertebrate (counts, percentages, influxes) records from a small Swiss lowland lake (Bichelsee, Switzerland) during the Lateglacial and Holocene. Associated deepwater oxygen availability reconstructions are also present in this dataset as well as the data used to draw the figures of the associated publication.
Dataset DOI: 10.5061/dryad.gb5mkkx47
Description of the data and file structure
Chironomid and other aquatic invertebrate data (counts, percentages, influxes) from Bichelsee (Switzerland). The R code used to calculate the CCAs based on modern aquatic invertebrate samples is also provided. The data and R code are Supplementary Information of the article "Dynamic deepwater invertebrate populations challenge the concept of oxygen-rich reference conditions for European lakes" published in Communications Earth & Environment.
Files and variables
File: R_code_for_CCAs.txt
Description: R code used to calculate the CCAs based on modern aquatic invertebrate samples in Swiss lakes with the Bichelsee downcore samples plotted passively.
File: Supplementary_Data_Publication.xlsx
Description: Chironomid and other aquatic invertebrates data (counts, percentages, influxes), 210Pb and 137Cs data as well as data used to draw the figures of the main manuscript
Variables
- Sample_id: sample identification number
- Top_seddepth: sediment depth of the upper margin (most recent) of the sample
- Top_sedage: age of the upper margin (most recent) of the sample
- Middle_seddepth: sediment depth of midpoint of the sample
- Middle_seddage: age of the midpoint of the sample
- Bottom_seddepth: sediment depth of the lower margin (oldest) of the sample
- Bottom_seddage: age of the lower margin (oldest) of the sample
Individual morphotypes counts (Invertebrates_Counts_all, Invertebrates_Counts_amal), percentages (Invertebrates_Percentages_amal) and influxes (Invertebrates_Influx_all) are given for each morphotypes in all the samples analysed.
In sheets Invertebrates_Counts_all and Invertebrates_Counts_amal, the Total Chironomidae column corresponds to the sum of all Chironomidae individuals (columns I-DI) identified in the corresponding sample, whereas the column Total aquatic invertebrates (incl. Chironomidae) corresponds to the sum of all Chironomidae individuals (column DJ) and all the other aquatic invertebrates (columns DL-DX).
Data_Figure 2: Development of invertebrate indicators of deepwater oxygen availability in Bichelsee and vegetation around the lake during the past 13,000 years.
Data_Figure 3: Development of chironomid influx in relation to vegetation, sedimentation processes and human activities near Bichelsee over the past 8000 cal. BP.
Data_Figure 4: Development of aquatic invertebrate assemblages, selected diatom groups and invertebrate-based indicators of deepwater oxygen availability in Bichelsee during the past 300 years.
File: Supplementary_Table_1.csv
Description: radiocarbon dates used to calculate the age-depth relationship of the Bichelsee sediment core.
Code/software
R Studio is required to read and perform the CCAs. The vegan package version 2.6-4 was used in our case.
Sediment samples were gently sieved under water with a 100 micrometer sieve. Chironomids and other aquatic invertebrates were then hand picked using a Bogorov tray under the stereomicroscope (20–50x magnification) and deposited on a microscope slide. The microscope slides were then air dried for a few hours before being permanently mounted using Euparal. Chironomid and other aquatic invertebrate remains were identified to the highest possible taxonomic resolution under a compound microscope (100–400x magnification). The full laboratory methods are presented in the associated publication.
For post identification data processing and deepwater oxygen availability reconstructions please see the associated publication in Communication Earth & Environment.