Biomass temporal stability increases at two spatial scales during secondary succession

Ecological stability has long been considered to change over succession,
but how secondary succession influences the relationship between diversity
and temporal stability of biomass production at different spatial scales
is poorly understood. We studied changes in plant diversity, functional
temporal stability (biomass production) and compositional temporal
stability (the latter two are hereafter referred to as functional
stability and compositional stability) and explored the stabilizing roles
of plant diversity at two spatial scales (small plots of 0.25 m2 area and
large transects of 1.25 m2 area) during secondary succession in a
subalpine meadow from 2003-2010. Our results showed that both plant
diversity and functional and compositional stability increased at the
small plot scale and large transect scale during secondary succession. As
secondary succession proceeded, higher average alpha diversity (i.e.,
species diversity at the plot scale) led to higher functional and
compositional stability at the plot scale by mainly species stability,
predominantly contributing to higher functional and compositional
stability at the large transect scale. In addition, Simpson-based beta
diversity (i.e., compositional dissimilarity among communities within the
same transect), while unaffected by succession, contributed to functional
stability at the large transect scale by promoting asynchronous dynamics
among communities. Synthesis: Our study highlights the stabilizing effects
of plant diversity across the two spatial scales during secondary
succession. Our findings provide the first empirical evidence that
biodiversity-mediated effects on ecosystem temporal stability strengthen
over successional time, suggesting that the stabilizing effects of
biodiversity should be considered across spatial and temporal scales in
the face of global changes and biodiversity loss.