Linking deadwood traits with saproxylic invertebrates and fungi in European forests - a review

Abstract

Biogeosciences and Forestry Biogeosciences and Forestry Linking deadwood traits with saproxylic invertebrates and fungi in European forestsa review Francesco Parisi (1-2) , Silvia Pioli (3-4) , Fabio Lombardi (5) , Giulia Fravolini (2) , Marco Marchetti (2) , Roberto Tognetti (1-4) Deadwood is a substantial component of forests playing a central role in many ecosystem processes. It provides habitats for a multitude of wood-dependent organisms, maintaining the ecosystem health and reducing the effect of natural disturbances. Deadwood is recognized as an indicator of local species diversity and contributes to the global carbon pools and nutrient cycles. Despite its importance, how saproxylic communities respond to deadwood dynamics across multiple spatial and temporal scales is still not clear. With the present review, we aim to summarize the effects of deadwood characteristics on the diversity and composition of saproxylic insects and fungi, with focus on European forests. We also discuss the influence of other biotic and abiotic components that indirectly affect these communities by altering wood continuity and variety. Niche differentiation is the main ecological driver of saproxylic organisms, as the presence of multiple microhabitats supports differently specialized taxa. The assemblage and richness of these saproxylic communities within forest ecosystems can be considered as indicators of climate-smart forestry trajectories. This aspect deserves to be regarded as a major target in sustainable forest management plans, especially in mountain areas, where the conservation of threatened species and the promotion of biodiverse forests are considered a priority.

Diversity of saproxylic beetle communities in chestnut agroforestry systems

“…Overall, these observations confirm our second hypothesis. In detail, cavities had positive effects on Bostrichidae, Tenebrionidae and Throschidae, whose larvae feed under the bark, building galleries that accelerate the decomposition processes, improving the quality of available substrates for fungi and bacteria, and then the colonization by secondary saproxylic insects (Parisi et al 2018), such as Cleridae and Melyridae (predators). Whereas, tree injuries and exposed wood were positively correlated with Cerambycidae, Curculionidae and Nitidulidae, probably in relationship with the absence of obstacles that facilitate spawning by adults of beetles (Quinto et al 2015).…”

“…Landscapes with high density of veteran trees and high diversity of associated fauna should be preserved for conservation purposes (Siitonen & Ranius 2015). General management rules can be envisaged to foster the biodiversity of saproxylic insects in these agroforestry systems (Parisi et al 2018). Guidelines will be useful to implement habitat 9260 conservation measures at the national level: (a) maintain as many veteran trees as possible, also at the edge of coppice stands, allowing for natural aging of trees and favoring the formation of suckers, without a complete removal of dead branches simultaneously; (b) ensure the continuous supply of both young and mature trees.…”

Saproxylic insects and fungi in deciduous forests along a rural–urban gradient

“…Several saproxylic insects are associated with wood‐decaying fungi (Biedermann & Vega, 2020) or even dependent on a particular fungal species for nutrition (Birkemoe et al., 2018; Floren et al., 2015; Jonsell & Nordlander, 2004). Together, these saproxylic organisms (invertebrates, fungi, bacteria and other microbes) accelerate the decay process of deadwood and are important for carbon sequestration, nutrient recycling, and overall biodiversity in the forests (Parisi et al., 2018; Stokland et al., 2012; Ulyshen, 2016).…”

Stand Structural Characteristics Are the Most Practical Biodiversity Indicators for Forest Management Planning in Europe

“…However, we did not assess it here as different indicators may have multiple impacts on ecosystem functioning and services outcomes. For instance, saproxylic beetles and other decomposers are important for nutrient cycling and thus the productivity of forests [36], whereas structural complexity provides niches for several species with different life traits and thus structurally complex ecosystems exhibit a high resilience towards environmental change [36][37][38][39].…”