Landscape context affects the success of habitat restoration: large‐scale colonization patterns of saproxylic and fire‐associated species in boreal forests

Abstract

Aim Restoration of habitats may be used as a conservation tool when ecosystems have lost their natural structure, dynamics or functioning over large areas. Controlled and planned use of fire could be an effective way to restore habitats of many threatened species in boreal forests where fire suppression has been effective. We asked whether the large‐scale landscape context affects the occurrence of rare and threatened species in forest habitats that have been burned to restore their fire‐related structures. Location Boreal forests in southern Finland. Methods We designed a large‐scale field experiment that included nine Pinus sylvestris forests (5–10 ha each) in southern Finland. Sites were located in two regions: (1) in eastern region with shorter management history and (2) in western region where intensive forestry has continued longer. We evaluated whether restoration of dead/burned wood is beneficial for rare and conservation‐dependent species and measured the recovery of pyrophilous and red‐listed insects (beetles and flatbugs) in burned forests, using standardized sampling effort. Altogether, 956 individuals of 29 red‐listed and pyrophilous species were sampled. Results Rare species colonized areas quickly, but there was a clear difference in species richness between the regions. The eastern forests harboured higher species richness after restoration. In these sites, the average species richness was 13.7 species per site, whereas in western forests it was 5.0 species per site. Similar pattern was also observed in subgroups: the corresponding numbers for pyrophilous species were 9.7 vs. 3.8, for red‐listed 8.7 vs. 2.3 and for red‐listed pyrophiles 4.7 vs. 1.2. Main conclusions Introducing fire back to boreal forests can aid in the recovery of rare species, but the landscape context considerably affects the success of restoring species. If restored habitats are located in landscapes that have lost their natural properties long ago, the success of restoration seems to be more challenging than in landscapes where habitats have been modified more recently.

Short-term changes in soil Munsell colour value, organic matter content and soil water repellency after a spring grassland fire in Lithuania

“…These ecosystems are strongly adapted to fire disturbance (Granstrom, 2001;Hylander, 2011;Pereira et al, 2013a, b). However, climate change, recent land-use change and fire suppression policies, may have important implications on the fire regime, fire severity and the role of fire in boreal environments (De Groot et al, 2013;Kouki et al, 2012;Van Bellen et al, 2010).…”

Forest restoration by burning and gap cutting of voluntary set-asides yield distinct immediate effects on saproxylic beetles

“…The reason for this is not clear and other studies have reported positive effects of fire on red-listed species (Hekkala et al 2014;Kouki et al 2012). However, the inherently low abundance of red-listed species increases the influence of stochasticity in the data and makes it more difficult to identify patterns.…”

“…However, the inherently low abundance of red-listed species increases the influence of stochasticity in the data and makes it more difficult to identify patterns. Other possible explanations for this lack of response are that intensively forest management in this landscape has resulted in an impoverished regional species pool of red-listed species, as shown in other studies (Kouki et al 2012); alternatively, that rare low density red-listed species should be expected to exhibit a slower response to fire than more abundant early successional saproxylic species. Hekkala et al (2014) reported that both the species richness and abundance of rare and red-listed species was higher the second year after fire compared to the first year after fire.…”

Ecological effects of disturbance-based restoration in boreal forests

“…Therefore, it appears that it may be difficult to restore aspen (or any other species) in forests if the ecosystem (and its surrounding matrix) is very far from its natural state. Because the dispersal ability varies greatly depending on the species to be restored (Jonsson et al 2005;Kouki et al 2012;Norros et al 2012), the effect of dispersal constraint is species-specific. Since aspen often regenerates through root suckers, a better result in terms of reaching restoration targets could perhaps be achieved by introducing the species by highly artificial means, for instance by the planting of trees.…”