We used stationary XRF spectrometry for analysing elemental composition of bank and streambed samples from Weiße Elster sub-basins (111 grids of 8*8 km). For XRF sample preparation freeze-dried catchment sediments (8 g) were seaved (2mm) to discard the gravel fraction and large organic matter. Further homogenization was undertaken by grinding the samples with a vibratory Retsch mill MM 200. We created uniform pellets by pressing the powdered samples with a carbon-based binding agent in a Vaneox press at 20 t for 2 min. We conducted elemental analyses in a He atmosphere using a Spectro Xepos energy dispersive XRF spectrometer.

At few sites (raster cells 56, 62, 69, 75, 82, 85, 93, 94) with complex fluvial stratigraphies, we took duplicate samples, marked with a "b"Measurement reproducibility; [character, unitless]:very good: very good reproducibility, highly reliable datavery good: very good reproducibility, highly reliable data; BUT: individual values are not secured, since concentrations are based on measurements with < 1000 pulses, not secured: Cl (column N/O)/samples with values 1000 pulses, secured: Se (column AR/AS)/ samples WE 004, WE 008, WE 010, WE 016, WE 018, WE 019, WE 022, WE024, WE025, WE 029, WE 030, WE 036, WE 059, WE 060, WE 075, WE 075b, WE 082, WE 082b, WE 087, WE 111moderate* : moderate reproducibility (values can definitely be used in terms of proportions within this data set), BUT: individual values are secured, since concentrations are based on measurements with >1000 pulses, secured: Co (column AD/AE)/samples WE 010, WE 015, WE 022-WE 025, WE 029, WE 030, WE 032, WE 049; Nb (column BD/BE)/samples WE 001, WE 003, WE 004, WE 006, WE 008, WE 010, WE 013, WE 014, WE 016-WE 019, WE 021-WE 023, WE 025-WE 032, WE 034, WE 036-WE 039, WE 041-WE 047, WE 050- WE 054; U (column CV/CW)/samples WE 059, WE 060, WE 075, WE 075b, WE 083, WE 089 BUT: individual values are not secured, since concentrations are based on measurements with 1000 pulses, secured: Mo (column BF/BG)/samples with values ≥ 10.4; Cd (column BJ/BK) samples WE 035; Sn (column BL/BM)/samples WE 010, WE 012, WE 016, WE 025, WE 030, WE 035, WE 046, WE 056, WE 056b, WE 066, WE 069, WE 069b, WE 075, WE 089, WE 089b, WE 093, WE 093b; Sb (column BN/BO)/samples WE 059, WE 069, WE 069b, WE 087, WE 094, WE 094b; Te (column BP/BQ)/samples WE 016, WE 026; I (colums BR/BS)/samples WE 016, WE 022, WE 030, WE 031, WE 045, WE 052; Cs (column BT/BU)/samples WE 016, WE 048; Hg (column CL/CM)/sample WE 010