Dataset: Park Grass 1993 soil transects across adjacent pairs of sub-plots with contrasting treatments

Soil transects were taken in August 1993 across the boundaries between four pairs of adjacent unlimed 'd' sub-plots with different fertiliser treatments on the Park Grass experiment, to assess the extent to which fertiliser in one plot affects the soil of the adjacent plot. All the soils were analysed for pH (in water); the soil from two pairs of plots were also analysed for Olsen P and exchangeable cations.
The data shows that there has been some mixing across the plot boundaries, possibly because, over 137 years (when the samples were taken) some fertiliser may not have been applied right up to the plot boundary or might have been spread over the boundary. It also seems likely that plant roots would have spread into adjacent plots looking for nutrients; the roots subsequently die leaving slightly enriched residues in the soil. However, in all cases, soil from > 50 cm away from the boundary is less variable. This is the data discussed in Poulton et al, 2026 (in preparation).