Data from: Regeneration processes on coarse woody debris in mixed forests: do tree germinants and seedlings have species-specific responses when grown on coarse woody debris?

Tree regeneration on coarse woody debris (CWD) is considered to be one the most ecologically valuable aspects of CWD in forest systems. However, most studies have focused solely on uncovering the differences in establishment and growth on CWD (regarded as a homogeneous substrate) in comparison with the forest floor. Our study concentrates on the underlying mechanisms of germinant and seedling colonization patterns and demographic responses relative to various properties of CWD. We analysed the effects of CWD properties (decay class, form, species and diameter) on: (i) germinant and seedling annual counts; (ii) annual germinant and seedling survival; and (iii) seedling growth and height. Our study comprised three species (beech, fir and spruce) over 7-year span in two old-growth stands in the Western Carpathians, and employed generalized linear models and mixed models to test for differences between species. CWD properties affected regeneration at the germination stage. There were some demographic differences between species relative to CWD properties. Decay class had the most pronounced effect on beech, not only on its establishment but also survival and growth. Beech and spruce established and survived in higher densities on beech CWD, while their height growth was enhanced on conifer-derived CWD, particularly on spruce CWD. Stumps enhanced establishment of all species and survival of conifer seedlings. Synthesis. Our study shows that CWD properties do influence seedling establishment, growth, height distribution and survival. Moreover, there may be trade-offs between seedling growth and survival among tree species growing on different species of CWD. This highlights the need to include CWD heterogeneity as a factor that can affect the role of CWD in regeneration in forest ecosystems.Numbers of germinants on CWDGerminants_counts.csvNumbers of seedlings on CWDSeedlings_counts.csvBeech germinants survival on CWDsurvival_germ_beech.csvFir germinants survival on CWDsurvival_germ_fir.csvSpruce germinants survival on CWDsurvival_germ_spruce.csvBeech seedling survival on CWDsurvival_seedl_beech.csvFir seedlings survival on CWDsurvival_germ_fir.csvSpruce seedlings survival on CWDsurvival_seedl_spruce.csvBeech seedlings height growth on CWDgrowth_seedl_beech.csvFir seedlings height growth on CWDgrowth_seedl_fir.csvSpruce seedlings height growth on CWDgrowth_seedl_spruce.cs