Density dependent processes
Incorporating density-dependent shifts in competitive interactions more
fully explained the directional changes in species group cover over time
(Fig 3, Table S2, S3). Broadly, global change treatments shifted
intraspecific and interspecific competition in ways that reduced net
competition for the dominant species but increased net competition for
subdominant and to a lesser extent, moderate and rare species (Fig 3,
S8). The major exception to this pattern was in the W plots, where we
observed an increase in net competition for the dominant species. In
addition, density-dependent species interactions shifted along
environmental gradients, primarily N, leading to non-linear abundance
distributions for subdominant species.