Decadal effects of landscape‐wide enrichment of dead wood on saproxylic organisms in beech forests of different historic management intensity

Abstract

Aim European temperate forests have lost dead wood and the associated biodiversity owing to intensive management over centuries. Nowadays, some of these forests are being restored by enrichment with dead wood, but mostly only at stand scales. Here, we investigated effects of a seminal dead‐wood enrichment strategy on saproxylic organisms at the landscape scale. Location Temperate European beech forest in southern Germany. Methods In a before–after control–impact design, we compared assemblages and gamma diversities of saproxylic organisms in strictly protected old‐growth forest areas (reserves) and historically moderately and intensively managed forest areas before and a decade after starting a landscape‐wide strategy of dead‐wood enrichment. Results Before enrichment with dead wood, the gamma diversity of saproxylic organisms in historically intensively managed forest stands was significantly lower than in reserves and historically moderately managed forest stands; this difference disappeared after 10 years of dead‐wood enrichment. The species composition of beetles in forest stands of the three historical management intensities differed before the enrichment strategy, but a decade thereafter, the species compositions of previously intensively logged and forest reserve plots were similar. However, the differences in fungal species composition between historical management categories before and after 10 years of enrichment persisted. Main conclusions Our results demonstrate that intentional enrichment of dead wood at the landscape scale is a powerful tool for rapidly restoring saproxylic beetle communities and for restoring wood‐inhabiting fungal communities, which need longer than a decade for complete restoration. We propose that a strategy of area‐wide active restoration combined with some permanent strict refuges is a promising means of promoting the biodiversity of age‐long intensively managed Central European beech forests.

Saproxylic species are linked to the amount and isolation of dead wood across spatial scales in a beech forest

“…bryophytes (Heilmann-Clausen et al 2005). This might be explained by strong competition between fungi in single dead wood pieces, with the consequence that only a few species build fruiting bodies (Heilmann-Clausen and Christensen 2004;Fukami et al 2010;Roth et al 2019). Probably due to these processes, other studies on wood-inhabiting fungi likewise did not show a relationship between local dead wood amount and community composition (Krah et al 2018) or changes in composition 10 years after dead wood enrichment (Roth et al 2019).…”

“…This might be explained by strong competition between fungi in single dead wood pieces, with the consequence that only a few species build fruiting bodies (Heilmann-Clausen and Christensen 2004;Fukami et al 2010;Roth et al 2019). Probably due to these processes, other studies on wood-inhabiting fungi likewise did not show a relationship between local dead wood amount and community composition (Krah et al 2018) or changes in composition 10 years after dead wood enrichment (Roth et al 2019). In contrast, Raabe et al (2010) found an effect of local dead wood amount on the community composition of epixylic bryophytes, and the models they used managed to explain 21% of the variance, a value our models did not reach.…”

Enhancing Ecologically Sustainable Management of Deadwood in Kenya’s Natural Forests

“…Active enrichment entails leaving parts of trees such as crowns or stem sections within harvest units [84]. Active enrichment has been found to increase deadwood amounts on the landscape level in young and formerly managed forests, thus enhancing biodiversity [85]. Other strategies involve the use of explosives and partial cutting of tree crowns [86].…”

Retention as an integrated biodiversity conservation approach for continuous-cover forestry in Europe

“…Lindenmayer 2017; Prevedello et al 2018) and dead wood (e.g. Roth et al 2018) to biodiversity, but more specific insights into their role in retention systems in temperate forests are limited (but see Vítková et al 2018; Asbeck et al 2019). Largely independent of the silvicultural system, studies from European forests have indicated that trees serving conservation purposes can improve biodiversity by increasing habitat diversity (Müller et al 2014; Gutzat and Dormann 2018), and that the abundance of tree-related microhabitats (e.g.…”