Discharges, radon fluxes, dissolved silicon, biogenic silica, stable silicon isotopes of water and sediment samples and XRF data from Lake 850, Northern Sweden

• Main Authors: Zahajská, Petra, Olid, Carolina, Shemesh, Aldo, Conley, Daniel J
• Format: Other/Unknown Material
• Language: English
• Published: PANGAEA 2021
• Subjects: Northern Sweden
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.929941; https://doi.org/10.1594/PANGAEA.929941

The stream discharges, dissolved silicon (DSi) concentrations, stable silicon isotopes, radon concentration, were measured on water samples taken in March, June, July, August and September 2019 in Lake 850, Northern Sweden. Additionally, total organic carbon (TOC), biogenic silica (BSi) concentrations, total nitrogen (TN) concentrations and carbon-nitrogen ratios (C/N), as well as concentrations of lead 210 (210Pb) were used for dating from the short sediment core, which was taken in March 2019 from the ice-covered lake are presented. All data were sampled to constrain the lake's recent water and silicon budget and to identify sources of dissolved silicon in the lake. Water samples for DSi and stable Si isotopes were sampled in HDPE acid-washed 125ml Nalgene bottles and filtered directly in the field through a 0.45μm Sterivex filter and further acidified using HCl to pH 2. Water samples for radon concentration measurements were samples in PET 2l bottles, where the water was let to overflow the bottle volume 3 times. The time of sampling and temperature was noted down. The samples were measured in the upcoming 24 hours by Rn-in-air alpha spectrometer RAD7 (Durringe Inc.). DSi was analyzed by molybdate blue method (Strickland and Parsons, 1972) using Smarrtchem 200, AMS System discrete analyzer. Stable silicon isotopes were performed on cation-exchange column cleaned (Georg et al., 2006) samples using MC-ICP-MS at Vegacenter, Stockholm. The sediment core analyzes of TOC, TN and C/N were measured on 5 to 10 mg of freeze-dried sediment using elemental analyzer COSTECH ECS4010. Further, the d13C and TOC was performed on de-calcified bulk sediment from 2019 core (250 mg in 50 ml of 5% HCl for 24 h (Brodie et al., 2011)) and analysed with an Elemental Analyser connected to a MAT-252 mass spectrometer at Weizmann Institute of Science, Rehovot. The biogenic silica concentrations were determined using weak alkaline extraction by Conley and Schleske, 2002 using 30mg of freeze-dried sediment reacting with 40ml of 0.1M ...