van Delden Lona lona.van.delden@awi.de Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam AWI Potsdam http://www.awi.de/en/institute/sites/potsdam/ https://ror.org/032e6b942 Höse Anna anna.hoese@awi.de Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam AWI Potsdam http://www.awi.de/en/institute/sites/potsdam/ https://ror.org/032e6b942 Jentzsch Katharina katharina.jentzsch@agro.au.dk 0000-0003-3163-4172 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam AWI Potsdam http://www.awi.de/en/institute/sites/potsdam/ https://ror.org/032e6b942 Aarhus University AU http://www.au.dk/en/ https://ror.org/01aj84f44 Treat Claire C claire.treat@agro.au.dk 0000-0002-1225-8178 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam AWI Potsdam http://www.awi.de/en/institute/sites/potsdam/ https://ror.org/032e6b942 Aarhus University AU http://www.au.dk/en/ https://ror.org/01aj84f44 2026 Year-round CO2, CH4, and N2O fluxes and quality criteria measured with automated chambers along a moisture gradient at Siikaneva bog, Finland (2022) dataset https://doi.pangaea.de/10.1594/PANGAEA.995280 2026-07-06T07:56:08 https://doi.pangaea.de/10.1594/PANGAEA.993356 This dataset contains year-round measurements of CO2, CH4, and N2O fluxes collected in 2022 using automated chambers along a moisture gradient at Siikaneva bog in southern Finland. Measurements were conducted at three ecosystem types representing different positions along the gradient from upland to wetland: a well-drained upland boreal forest, an intermediate site, and an open bog hollow. Each site was equipped with four automated chambers to provide spatial replication, including three transparent chambers and one opaque chamber. The opaque chamber measures the soil respiration compared to the Net Ecosystem Exchange (NEE) of the transparent chambers. The chambers close one after another fol-lowing a set schedule, alternating the chambers from each microsite for the best spread over the course of the day. A multiplexer switches the sample loop between chambers with several minutes of flush time with ambient air before and after each measurement. The measurement setup allows for 48 separate measure-ments per day for 12 chambers overall, equalling to four fluxes per chamber and day. The chamber system (SUVILUMI OY, Finland) was built and implemented based on the design of Koskinen et al. (2014), who describe the system operations and performance in detail. Briefly, the basic system structure includes a stainless-steel frame with the chamber as moveable lid, a stainless-steel collar inserted 10 cm into the ground, a waterproof actuator (Linak Techline LA-35, Linak, 2009) to move the lid and threaded steel rod legs and bolts, on which the weight of the construction rests. U profiles under the edges of the chamber lids, insulated with foam tape, ensure air-tight sealing. During winter, the frame was lifted to add snow extensions according to the developing snow height. The chambers dimensions are 60 cm x 60 cm x 40 cm (l x w x h; ⁓144 L) to include shrubs. According to the extensions and individual grow-ing vegetation for each replicate, the additional headspace of the collar was added to the chamber head-space by measuring the vegetation or snow height inside the collar on four sides and taking the average. A fan ensures constant mixing of the chamber headspace atmosphere. A pressure vent ensures equalization during changing environmental conditions and sampling. To avoid heat stress on the plants during the day but include traceable changes of lower concentrated gas-es such as CH4 and N2O, we compromised the chamber closure to 10 minutes during summer but extended to 20 minutes during autumn and winter (since 23.09.2022) to increase the detection limit of small fluxes, N2O in particular. During chamber closure time, a headspace gas sample is being transported into a near-by shed through polyurethane tubes by a Picarro internal vacuum pump (flow rate up to 230 sccm) and analyzed immediately by an in-situ Picarro G2508 (Picarro, USA), which measures CO2, CH4, N2O and H2O continuously once per second with cavity ring-down spectroscopy (CRDS). According to the analyzer data sheet by Picarro (2024), the measurement precision at 1 minute and 5 minutes is <10 and <5 ppb for N2O, <7 and <5 ppb for CH4, <300 and <200 ppb for CO2. Afterwards the gas sample is being discarded through a vent (open-loop). This open-loop setup allows for the maximum chamber-to-analyzer distance of 60 m at the upland forest microsite. The lag times resulting from the various sample line lengths was accounted for during the data processing and flux calculation. The flux calculations were done in the R environment (R version 4.1.2). All fluxes are calculated based on their scheduled chamber closure time and converted according to the chamber specific volume and tem-perature during the measurement. Temperature measurements (every 3 seconds) were interpolated to cor-rect the concentration measurements (per second, Hz) before calculating the fluxes by linear regression. Non-linear flux calculation approaches were tested for the data set, such as the HMR package in R (Pedersen, 2010), but due to extreme over- or underestimated fluxes on some occasions, it was decided that the linear fit was overall the better alternative. A flagging procedure provides the data set with informative quality control (QC), which includes three main components. First, system functioning parameters such as line pressure and actuator voltage sig-naled for system failure and flagged the fluxes that were measured at that time. For the second flagging component, the regression coefficient (R2) and the root mean square error (RMSE) were determined for linear fitted fluxes to filter for factors such as dilution, saturation effects or interference. Fluxes of all three gases were flagged when the CO2 concentration R2 over the measurement time frame was below 0.85. Fluxes were also flagged when three times the flux specific RMSE exceeded the RMSE of the no-flux zone per measurement. The no-flux zone was determined by sampling ambient air before and after the meas-urement per chamber per measurement time. Flux measurements close to zero, which fall within the no-flux zone were kept as is and not discarded based on their R2 or RMSE since that would have eliminated all near-zero measurements. The third QC component was based on the field log and visual observations through the Phenocams to exclude times of maintenance or disturbances. 2024 G2508 Analyzer Datasheet other Picarro, Inc. https://www.picarro.com/g2508_analyzer_datasheet Koskinen Markku 0000-0002-9473-6064 Minkkinen Kari kari.minkkinen@helsinki.fi Ojanen Paavo paavo.ojanen@luke.fi 0000-0003-4785-3521 Kämäräinen Matti Laurila Tuomas Tuomas.Laurila@fmi.fi Lohila Annalea 0000-0003-3541-672X 2014 Measurements of CO2 exchange with an automated chamber system throughout the year: challenges in measuring night-time respiration on porous peat soil journal article Biogeosciences 11(2) https://doi.org/10.5194/bg-11-347-2014 347-363 Pedersen A R Petersen S O Schelde K 2010 A comprehensive approach to soil‐atmosphere trace‐gas flux estimation with static chambers journal article European Journal of Soil Science 61(6) https://doi.org/10.1111/j.1365-2389.2010.01291.x 888-902 24.1967 24.1967 61.8372 61.8372 24.1967 61.8372 2022-01-01T00:00:00 2022-12-31T23:30:00 160.0 160.0 FluxWIN The role of non-growing season processes in the methane and nitrous oxide budgets in pristine northern ecosystems https://www.awi.de/en/science/junior-groups/fluxwin.html Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven AWI https://www.awi.de/ https://ror.org/032e6b942 European Research Council ERC https://doi.org/10.13039/501100000781 851181 The role of non-growing season processes in the methane and nitrous oxide budgets in pristine northern ecosystems https://doi.org/10.3030/851181 FN-Land_2022_SiikanevaPeatland_continuous 61.8372 24.1967 Siikaneva bog, Finland 160.0 2022-01-01T00:00:00 2022-12-31T23:30:00 FN-Land_2022_SiikanevaPeatland FN-Land_2022_SiikanevaPeatland FluxWIN/Siikaneva FluxWIN/Siikaneva 2022-02-26T00:00:00 2022-02-26 2022-10-10T00:00:00 2022-10-10 AWI Arctic Land Expedition Treat, Claire C Treat, Claire C AWI Arctic Land Expedition Multiple investigations MULT 344758 CC-BY-4.0 Creative Commons Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/ Alarm code: 1st digit: Picarro warning (True = "2", False= "1") 2nd digit: Actuator fault (<2.5 = "2", otherwise "1") 3rd digit: P_line (<0.5 = "2", otherwise "1") 4th digit: Alarm warning (True = "2", False= "1") 5th digit: Alarm out (True = "2", False= "1") 6th digit: CO2 regression R² (<0.85 = "2", otherwise "1") 7th digit: CO2 RMSE (>3x ambient SD = "2", otherwise "1") 8th digit: CO2 concentration (outside 300-600 µmol/m² = "2", otherwise "1") 9th digit: CH4 concentration (outside 1-3 µmol/m² = "2", otherwise "1") 10th digit: N2O concentration (outside 0.2-0.4 µmol/m² = "2", otherwise "1") DATE/TIME Date/Time http://en.wikipedia.org/wiki/ISO_8601 Time T http://dbpedia.org/resource/Time van Delden Lona lona.van.delden@awi.de Date/Time Site Site site Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de Description of Chamber site: Site along moisture gradient: A (upland forest), B (intermediate), C (bog); chamber (spatial replicate) within site: 1-3: transparent chambers, 4: opaque chamber Site (Description of Chamber site: ...) Carbon dioxide CO2 µmol Amount of Substance N http://dbpedia.org/resource/Amount_of_substance Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_st_conc_umol: Initial CO2 concentration in chamber CO2 [µmol] (CO2_st_conc_umol: Initial CO2...) Carbon dioxide, flux CO2 flux µg/m**2/h carbon dioxide http://purl.obolibrary.org/obo/CHEBI_16526 flux http://purl.obolibrary.org/obo/PATO_0001030 Mass Accumulation Rate/Flux Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_ug_m2_h: CO2 flux rate CO2 flux [µg/m**2/h] (CO2_ug_m2_h: CO2 flux rate) Coefficient of determination R**2 http://en.wikipedia.org/wiki/Coefficient_of_determination Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_rsquared: R-squared value for CO2 regression R**2 (CO2_rsquared: R-squared value...) Root mean square error RMSE mean Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_rmse: R-squared value for CO2 regression [µg/m²/h] RMSE (CO2_rmse: R-squared value for...) Data points Data points # Abundance or Count Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_num_of_data: Number of data points used in CO2 regression Data points [#] (CO2_num_of_data: Number of da...) Carbon dioxide, ambient, average CO2 amb avg µg/m**2 carbon dioxide http://purl.obolibrary.org/obo/CHEBI_16526 average Mass per Area Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_amb_avg_umol_m2: Ambient average CO2 concentration CO2 amb avg [µg/m**2] (CO2_amb_avg_umol_m2: Ambient ...) Carbon dioxide, ambient, standard deviation CO2 std dev ± carbon dioxide http://purl.obolibrary.org/obo/CHEBI_16526 standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_amb_SD: Standard deviation of ambient CO2 concentration CO2 std dev [±] (CO2_amb_SD: Standard deviatio...) Carbon dioxide, flux, at zero flux condition CO2 zero flux µg/m**2/h carbon dioxide http://purl.obolibrary.org/obo/CHEBI_16526 flux http://purl.obolibrary.org/obo/PATO_0001030 Mass Accumulation Rate/Flux Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CO2_zeroflux_ug_m2_h: CO2 flux calculated at zero flux condition CO2 zero flux [µg/m**2/h] (CO2_zeroflux_ug_m2_h: CO2 flu...) Methane CH4 µmol methane http://purl.obolibrary.org/obo/CHEBI_16183 Amount of Substance N http://dbpedia.org/resource/Amount_of_substance Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_st_conc_umol: Initial CH4 concentration in chamber CH4 [µmol] (CH4_st_conc_umol: Initial CH4...) Methane, flux CH4 flux µg/m**2/h Mass Accumulation Rate/Flux Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_ug_m2_h: CH4 flux rate CH4 flux [µg/m**2/h] (CH4_ug_m2_h: CH4 flux rate) Coefficient of determination R**2 http://en.wikipedia.org/wiki/Coefficient_of_determination Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_rsquared: R-squared value for CH4 regression R**2 (CH4_rsquared: R-squared value...) Root mean square error RMSE mean Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_rmse: Root Mean Square Error for CH4 concentration fit [µg/m²/h] RMSE (CH4_rmse: Root Mean Square Er...) Data points Data points # Abundance or Count Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_num_of_data: Number of data points used in CH4 regression Data points [#] (CH4_num_of_data: Number of da...) Methane, ambient, average CH4 amb avg µg/m**2 methane http://purl.obolibrary.org/obo/CHEBI_16183 average Mass per Area Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_amb_avg_umol_m2: Ambient average CH4 concentration CH4 amb avg [µg/m**2] (CH4_amb_avg_umol_m2: Ambient ...) Methane, ambient, standard deviation CH4 std dev ± methane http://purl.obolibrary.org/obo/CHEBI_16183 standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_amb_SD: Standard deviation of ambient CH4 concentration CH4 std dev [±] (CH4_amb_SD: Standard deviatio...) Methane, flux, at zero flux condition CH4 zero flux µg/m**2/h methane http://purl.obolibrary.org/obo/CHEBI_16183 flux http://purl.obolibrary.org/obo/PATO_0001030 Mass Accumulation Rate/Flux Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de CH4_zeroflux_ug_m2_h: CH4 flux calculated at zero flux condition CH4 zero flux [µg/m**2/h] (CH4_zeroflux_ug_m2_h: CH4 flu...) Nitrous oxide N2O µmol nitrous oxide Amount of Substance N http://dbpedia.org/resource/Amount_of_substance Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_st_conc_umol: Initial N2O concentration in chamber N2O [µmol] (N2O_st_conc_umol: Initial N2O...) Nitrous oxide, flux N2O flux µg/m**2/h Mass Accumulation Rate/Flux Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_ug_m2_h: N2O flux rate N2O flux [µg/m**2/h] (N2O_ug_m2_h: N2O flux rate) Coefficient of determination R**2 http://en.wikipedia.org/wiki/Coefficient_of_determination Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_rsquared: R-squared value for N2O regression R**2 (N2O_rsquared: R-squared value...) Root mean square error RMSE mean Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_rmse: Root Mean Square Error for N2O concentration fit [µg/m²/h] RMSE (N2O_rmse: Root Mean Square Er...) Data points Data points # Abundance or Count Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_num_of_data: Number of data points used in N2O regression Data points [#] (N2O_num_of_data: Number of da...) Nitrous oxide, ambient, average N2O amb avg µg/m**2 nitrous oxide average Mass per Area Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_amb_avg_umol_m2: Ambient average N2O concentration N2O amb avg [µg/m**2] (N2O_amb_avg_umol_m2: Ambient ...) Nitrous oxide, ambient, standard deviation N2O std dev ± nitrous oxide standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_amb_SD: Standard deviation of ambient N2O concentration N2O std dev [±] (N2O_amb_SD: Standard deviatio...) Nitrous oxide, flux, at zero flux condition N2O zero flux µg/m**2/h nitrous oxide flux http://purl.obolibrary.org/obo/PATO_0001030 Mass Accumulation Rate/Flux Gas analyzer, Picarro, G2508 van Delden Lona lona.van.delden@awi.de N2O_zeroflux_ug_m2_h: N2O flux calculated at zero flux condition N2O zero flux [µg/m**2/h] (N2O_zeroflux_ug_m2_h: N2O flu...) Code Code van Delden Lona lona.van.delden@awi.de Alarm code indicating various warnings, concatenated based on specific conditions Code (Alarm code indicating various...) CurationLevelC Enhanced curation https://wiki.pangaea.de/wiki/Curation_levels bog Boreal greenhouse gas fluxes Methane moisture gradient Nitrogen Peatland quality control author116504 author117769 author117770 author117771 author117772 author117773 author57937 author62170 author64272 author78906 author88091 author88095 author91849 award382 basis5344 campaign3373168 campaign48838 curlevel30 event3412793 funder20666 geocode1599 geocode1600 geocode1601 geocode8128 inst20913 inst21044 inst32 journal2146 journal5328 license21 method10667 method12165 param117536 param181493 param181497 param48491 param50007 param520582 param563675 param565287 param565288 param565289 param565290 param565291 param565292 param565293 param565294 param565295 param565296 param565297 param565298 param94636 pi91849 project4516 ref140138 ref140139 ref140140 term1073490 term1073540 term1073620 term2662962 term37764 term37810 term396 term40464 term40958 term43762 term43895 term43975 term44025 term44027 term47444 term47665 term625 term67887 term72906 term74511 term74681 term77366