Disturbance interval modulates the starting point for vegetation succession

Abstract

Increased frequency and new types of disturbances due to global change calls for deepened insights into possible alterations of successional pathways. Despite current interest in disturbance interactions there is a striking lack of studies focusing on the implication of decreasing times between disturbances. We surveyed forest-floor vegetation (vascular plants and bryophytes) in a Pinus sylvestris-dominated, even-aged production forest landscape, unique due to presence of stands under a precisely dated disturbance interval gradient, ranging 0-123 yr between clearcutting and a subsequent mega-fire. Despite a dominance of early-successional species in all burned stands five years after fire, progression of succession was linked to time since the preceding clearcutting disturbance. This was most clearly seen in increased frequency with time since clearcutting of the dominant, latesuccessional dwarf shrub Vaccinium myrtillus, with surviving rhizomes as an important mechanism for post-fire recovery. Our results demonstrate the role of legacy species as significant drivers of succession. We conclude that the starting point for succession is modulated by disturbance interval, so that shortened intervals risk reducing development towards late-successional stages. We suggest that a decrease in long successional sequences caused by more frequent disturbances may represent a general pattern, relevant also for other forest types and ecosystems.

Stochastic Processes Shape Bacterial Community Diversity Patterns along Plant Niche Gradients

“…Once restored to a certain degree, a relatively stable grassland community is established, and a coexistence relationship may be formed between grasses and shrubs in different ecological niches within the community [26]. The theory of vegetation succession suggests that under suitable temperature, moisture, soil nutrients, and other conditions, stable grassland communities transform into shrub communities over time [27,28]. Thus, many studies have focused on rhizosphere microbial diversity and rich-ness during succession [12,29,30].…”

Early Effect of Microtopography of Site Preparation on Vegetation Restoration in Young Mixed Hemiboreal Stands

“…Due to increased numbers of ruderal and light-demanding species, the number of plant species is highest in the first ten years after felling but decreases with stand age (Gustienė et al, 2019;Tullus et al, 2022;Zobel et al, 2007). Species diversity value may be temporally increased in after clearcut, but in terms of succession, species composition and the presence of old forest-specific species are more important (Gustafsson et al, 2021).…”

The effect of site preparation on vegetation restoration in young hemiboreal mixed stands

“…Non-typical forest vascular plants, drought-tolerant, light-demanding and pioneer species such as Rubus idaeus (L.) dominate in the first few years after logging, but with further succession, bryophytes and dwarf shrub species typical of old boreal forests reoccupy the area (Hannerz and Hånell 1997, Engelmark and Hytteborn 1999, Uotila and Kouki 2005, Bergstedt et al 2008. Species diversity value may be temporally increased after clearcut, but in terms of succession, species composition and the presence of old forest-specific species are more important (Gustafsson et al 2021).…”