Data from: Community assembly and functional diversity along succession post-management

1. Despite extensive development of successional theory, few empirical
studies have evaluated whether existing models are applicable to
human-modified landscapes. Seasonally dry tropical forests are
experiencing widespread transformation, and represent a critical system to
assess in a successional framework to infer the mechanisms that shape
assembly of secondary forests post-management. 2. We used a functional
trait-based approach to assess changes in community assembly mechanisms
along succession in secondary dry forests of varying stages following
abandonment of cattle activity, as well as nearby old-growth forests. We
evaluated whether re-assembly proceeded consistent with existing theory,
in early successional stages via habitat filtering, leading to reduced
trait range, and via competitive exclusion in later stages, leading to
increased trait evenness. Using three orthogonal traits and two functional
diversity indices we tested for evidence of assembly mechanisms along
resource axes that may be particularly important to dry forest systems,
dynamic changes in habitat filtering and competitive exclusion, and
potential legacy effects of management. 3. We found little support of a
progression from habitat filtering to competitive exclusion, with the
exception of dispersion patterns for specific leaf area and multi-variate
functional richness. Water may underlie species sorting in most stages, as
evidenced by range reduction in wood density, and might be a resource
particularly important to dry forest assembly. Early successional stages
displayed an unexpected pattern of low evenness, which may be due to
initial stand composition including remnants and resprouts, a regeneration
strategy typical to dry forest species. Beyond influencing initial
conditions, management legacy was apparent in late secondary forests,
which differed in range, even dispersion, and functional richness from
old-growth forests, suggesting the operation of different assembly
mechanisms. 4. The departures from expectations suggest the need to
re-assess successional models to include effects of management legacies on
the operation of community assembly mechanisms in human-modified
landscapes, as well as characteristics that distinguish wet and dry forest
dynamics.