Spatial and bulked soil and herbage selenium concentrations in different pasture types in SW England

The data included in this dataset are selenium (Se) concentrations of soil and herbage from a number of pasture fields, with additional soil, herbage and farm management data either available as part of this data package or in linked sources. For 20 fields, bulked soil samples and bulked herbage samples (not from the same locations) were taken to be representative of the fields. For three of these fields, additional sampling at point locations was undertaken, with both soil and herbage being taken from the same places. For herbage and soil, total Se was measured. In addition, soil Se bioavailability was assessed through sequential fractionation. Fractions F0 and F1 (see below for methods) are assumed to be soluble Se; fraction F2 is exchangeable Se; fraction F3 is associated with Fe, Al and Mn oxides, carbonates and hydrolysable organic matter, and is assumed to be not readily available to plants; fraction F4 is the residual fraction that is elemental, insoluble and unavailable. The experiment took place on the North Wyke Farm Platform (NWFP), a UK National Capability in SW England. The NWFP is split into a number of self-contained farms (‘farmlets’) that are managed according to different operation philosophies or practices. At the time of the experiment, there were three farmlets on the NWFP with different pasture management strategies. Permanent pasture (PP), a perennial ryegrass monoculture (HS) which was sown with a high sugar Lolium perenne cv. AberMagic, and a white clover/perennial ryegrass mix (WC) with the same ryegrass variety as the HS pasture. The PP and HS pastures received N fertilizer at a standard rate, but the WC pastures did not due to the inclusion of a legume. Fields within a farmlet are cut for silage and grazed by cattle and sheep. The NWFP is highly instrumented and monitored, and core NWFP datasets are open and include in-situ water flow and chemistry taken at 15-minute intervals; 15-minute Met measurements; 15-minute soil moisture measurements; 30-minute GHG emissions; soils, crop and botanical field survey data; livestock and crop performance data; and farm operational activities, and contextual information is also available. See https://nwfp.rothamsted.ac.uk/. Registration is required, but all data is freely available for download. Further information about the NWFP, including Guides and Information about the data collected, are available at http://resources.rothamsted.ac.uk/farmplatform.