Data on the carbon and nitrogen cycling in sediments from rivers within the Hampshire Avon catchment, UK. The dataset includes functional gene data, anion and cation concentrations, methane production and oxidation potential, carbohydrates concentrations, pigment data, and particle size data. Data were collected between February 2013 and November 2014. Data were collected to address the hypotheses of how the functional microbial community involved in carbon and nitrogen cycling changed seasonally and with geology. Data were collected as part of the project "The role of lateral exchange in modulating the seaward flux of C, N, P", funded under NERC's Macronutrients Cycles research programme. Full details about this dataset can be found at https://doi.org/10.5285/976602b3-a58d-460c-a52d-088d0bb09989
