Data from: Variation in three community features across habitat types and scales within a 15-ha subtropical evergreen-deciduous broadleaved mixed forest dynamics plot in China

The evergreen and deciduous broadleaved mixed forests (EDBMFs) belong to
one of the ecosystems most sensitive to environmental change, however,
little is known about the environmental determinants for their plant
diversity and forest structure at different habitat types and spatial
scales. Here, we used data from a 15-ha (300×500 m) forest dynamic plot
(FDP) of an old-growth EDBMF to examine the patterns and determinants of
the three community features (stem abundance, rarefied species richness
and basal area) in three habitat types (ridge, hillside and foothill) and
at three spatial scales (20×20 m, 50×50 m and 100×100 m). We found that
the three community features significantly changed with habitat type, but
only one of them (rarefied richness) changed with scale. Among spatial
scales, the principle environmental factors that widely affected community
features were pH, SOM and TP, while these effects only taken place at
certain habitat. Variations in the three community features explained by
soil conditions were generally greater than those explained by
topographical conditions. With changes in habitat type, the proportion of
variations explained by environmental conditions was 31-53%, 8-25%, and
18-26% for abundance, rarefied richness and basal area (BA), respectively.
With increasing spatial scale, the variations explained by environmental
conditions were 44-75% for abundance, 28-95% for rarefied richness, and
18-86% for BA. Our study demonstrated that environmental factors had great
impacts on the plant diversity and forest structure in the EDBMFs,
especially the soil factors such as pH. In addition, the importance of the
environmental determinants on these community features was highly related
to the spatial scale.