The dataset contains chemistry data from streambed porewater (10 and 20 cm) and surface water, as well as nitrogen chemistry data at 2.5 cm resolution within the upper 15 cm of the streambed. The dataset includes concentrations of dissolved organic carbon (DOC), carbon dioxide, methane, ammonium, nitrate, nitrite and nitrous oxide, and isotopic ratios of δ13CCO2, δ15NNO3+NO2 and δ18ONO3+NO2. Also included are measurements of dissolved oxygen and temperature. Samples were collected from three reaches within the stream, an upstream sandy reach, a mid-stream sandy reach and a downstream gravel reach. The work was carried out with Natural Environment Research Council (NERC) funding through a PhD (NERC award number 1602135), grant (NE/L004437/1) and Life Sciences Mass Spectrometry Facility grant (CEH_L102_05_2016).
Publication date: 2018-12-19
This dataset is part of the following
Water samples were collected from the streambed (10 and 20 cm from multilevel piezometers) and the surface water in July 2016, October 2016, January 2017 and March 2017. Dissolved oxygen concentration and temperature was measured in-situ using a YSI ProODO or EcoSense ODO200 meter, water samples were filtered (0.45 then 0.22 um) and frozen until analysis. Gas samples were produced in-situ from porewaters with ultrapure helium using a headspace equilibrium method. Gas samples were stored dark, at room temperature, until analysis. Diffusive equilibrium in thin-film (DET) gels were deployed 72 hours prior to sampling, and were removed at the same time as porewater sampling, sliced within 25 minutes and stored cold (4 °C) until processing. DET gel slices were processed in the laboratory by weighing them, adding 5 ml ultrapure water and shaking for 24 hours. DOC concentrations were measured on a Shimadzu TOC analyser (TOC-L CPH with ASI-L autosampler), ammonium, nitrate and nitrite concentrations were measured on a Skalar San++ continuous flow analyser, greenhouse gas concentrations were measured on Agilent 7890A Gas Chromatographs fitted with thermal conductivity detector for carbon dioxide, flame ionization detector for methane and micro electron capture detector or electron capture detector for nitrous oxide. Headspace greenhouse gas concentrations were converted to porewater concentrations using Henry’s constant. Nitrate isotopes were determined by converting nitrate+nitrite to nitrous oxide using denitrifying bacteria, which was subsequently measured on a GEO 20:20 gas chromatograph isotope ratio mass spectrometer, carbon dioxide isotopes were determined on a Isoprime Tracegas Preconcentrator coupled to an isotope ratio mass spectrometer. Results from the experiments were entered into an Excel spreadsheet and exported as a comma separated value file (.csv) for ingestion into the EIDC.