Summary data of chamber-based oxygen and methane consumption and production in the streambed and outgassing of carbon dioxide and methane to the atmosphere collected seasonally for six tributaries of Hampshire River Avon (UK) during 2013-2014.

Data were collected in six headwater reaches of the lowland catchment of the Hampshire River Avon (UK), specifically on Chalk River Ebble and River Wylye, Greensand River Nadder and West Avon, and clay River Sem and Sem Tributary River Priors between April 23^th 2013 and February 10^th 2014. The setup consists of transparent and dark Perspex chambers (0.5 L enclosed volume, 73 cm² surface area) mounted on a steel-ring, which were used to quantify O₂ production and CH₄ release in the light and benthic O₂ consumption and CH₄ release in the dark, respectively. Concentrations of CH4 were obtained based on discrete samples (GC analysis); O₂ from Clark-type oxygen microelectrodes connected to an Unisense Under-Water Meter. The floating chambers consists of an inverted plastic bowl covered in reflective aluminum tape, fitted with a polyurethane tubing sample port to allow for gas-sampling (CH₄ measurements) and a SenseAir CO₂ sensor <br>A more comprehensive description of the datasets is available from the manuscript below.Rovelli L., L. A. Olde, C. M. Heppell, A. Binley, G. Yvon-Durocher, R. N. Glud, M. Trimmer. (2022) Contrasting biophysical controls on carbon dioxide and methane outgassing from streams. <i>Journal of Geophysical Research: Biogeosciences </i>127(1): e2021JG006328, doi:10.1029/2021JG006328