This dataset contains time series observations of surface-atmosphere exchanges of net ecosystem carbon dioxide exchange (NEE), sensible heat (H) and latent heat (LE), and momentum (τ) measured at two managed lowland peatland environments in the East Anglian Fens, England, UK. One site is managed for the production of horticultural salad crops, the other is an area of managed grassland. Turbulent flux densities were monitored using the micrometeorological eddy covariance (EC) technique between 10th November 2016 and 25th September 2018 at the cropland site, and between 27th April 2017 and 31st March 2019 at the grassland. The dataset includes ancillary weather and soil physics observations, as well as variables describing atmospheric turbulence and the quality of the turbulent flux observations.