Rare species, functional groups, and evolutionary lineages drive successional trajectories in disturbed forests

Abstract

Following natural disturbances, additional anthropogenic disturbance may alter community recovery by affecting the occurrences of species, functional groups, and evolutionary lineages. However, our understanding of whether rare, common, or dominant species, functional groups, or evolutionary lineages are most strongly affected by an additional disturbance, particularly across multiple taxa, is limited. Here, we used a generalized diversity concept based on Hill numbers to quantify the community differences of vascular plants, bryophytes, lichens, wood‐inhabiting fungi, saproxylic beetles, and birds in a storm‐disturbed, experimentally salvage logged forest. Communities of all investigated species groups showed dissimilarities between logged and unlogged plots. Most species groups showed no significant changes in dissimilarities between logged and unlogged plots over the first seven years of succession, indicating a lack of community recovery. In general, the dissimilarities of communities were mainly driven by rare species. Convergence of dissimilarities occurred more often than divergence during the early stages of succession for rare species, indicating a major role in driving decreasing taxonomic dissimilarities between logged and unlogged plots over time. Trends in species dissimilarities only partially match the trends in dissimilarities of functional groups and evolutionary lineages, with little significant changes in successional trajectories. Nevertheless, common and dominant species contributed to a convergence of dissimilarities over time in the case of the functional dissimilarities of wood‐inhabiting fungi. Our study shows that salvage logging following disturbances can alter successional trajectories in early stages of forest succession following natural disturbances. However, community changes over time may differ remarkably in different taxonomic groups and are best detected based on taxonomic, rather than functional or phylogenetic dissimilarities.

Estimating retention benchmarks for salvage logging to protect biodiversity

“…Differences in taxonomic, functional and phylogenetic diversity of bird communities sampled in unlogged disturbed plots and salvage-logged plots can persist or even increase over 17 years following fire and wind disturbance 11 . Similarly, a multi-taxa approach, including vascular plants, bryophytes, lichens, wood-inhabiting fungi, saproxylic beetles, and birds, revealed a limited change in dissimilarities between unlogged disturbed plots and salvage-logged plots over the first seven years of succession 30 . In that study, the remaining dissimilarities in communities were caused primarily by the presence or absence of rare species 30 , quantified based on a similar statistical framework as in our study.…”

“…Similarly, a multi-taxa approach, including vascular plants, bryophytes, lichens, wood-inhabiting fungi, saproxylic beetles, and birds, revealed a limited change in dissimilarities between unlogged disturbed plots and salvage-logged plots over the first seven years of succession 30 . In that study, the remaining dissimilarities in communities were caused primarily by the presence or absence of rare species 30 , quantified based on a similar statistical framework as in our study. Our results therefore imply that the positive effect of retention during salvage logging on biodiversity remains over the course of early succession.…”

“…1 , bold green curve). These species are of high conservation interest and contribute greatly to community changes resulting from salvage logging 30 . We apply this statistical approach to a global dataset of studies with sampling units selected randomly from both naturally disturbed and salvage-logged areas to estimate logging benchmarks for naturally disturbed forests, namely a) the portion of naturally disturbed forest that must be spared from salvage logging to maintain 90% of the species richness associated with naturally disturbed and not salvage logged forest; and conversely b) the portion of species richness associated with naturally disturbed forest that remains when 50% of the area of a disturbed forest is salvage logged.…”

Primary determinants of communities in deadwood vary among taxa but are regionally consistent

“…Among other factors, the relative contribution of rare, common and dominant (i.e. based on abundances) species in local communities is thought to be particularly important in determining such dissimilarities (Norden et al 2009, 2017, Thorn et al 2020). While the presence of dominant species may stabilize, rare species are frequently subject to extinction and immigration (Li et al 2016).…”

Salvage logging changes the taxonomic, phylogenetic and functional successional trajectories of forest bird communities

“…These changes in specialist and generalist species may also apply to rare functional groups or rare evolutionary lineages (Olden, 2006). However, empirical tests of whether the strength of community response to salvage logging varies depending on the relative contribution of dominant versus rare (for abundance data) or common versus rare (for occurrence data) species are lacking (but see Thorn et al, 2020).…”