Plant nitrogen preferences mirror underground nitrogen cycling in natural ecosystems (Dataset 1 & 2)

We compiled data from 66 15N labeling studies, yielding 336 triplet observations, each consisting of plant organic-N, ammonium-N, and nitrate-N uptake measurements (Dataset 1). Additionally, 2030 observations of gross soil N transformations from 270 studies were compiled to predict the spatial variation of these rates globally, with the aim of populating Dataset 1.