Drivers of CO2 Emission Rates from Dead Wood Logs of 13 Tree Species in the Initial Decomposition Phase

Abstract

Large dead wood is an important structural component of forest ecosystems and a main component of forest carbon cycles. CO2 emissions from dead wood can be used as a proxy for actual decomposition rates. The main drivers of CO2 emission rates for dead wood of temperate European tree species are largely unknown. We applied a novel, closed chamber measurement technique to 360 dead wood logs of 13 important tree species in three regions in Germany. We found that tree species identity was with 71% independent contribution to the model (R 2 = 0.62) the most important driver of volume-based CO2 emission rates, with angiosperms having on average higher rates than conifers. Wood temperature and fungal species richness had a positive effect on CO2 emission rates, whereas wood density had a negative effect. This is the first time that positive fungal species OPEN ACCESSForests 2015, 6 2485 richness-wood decomposition relationship in temperate forests was shown. Certain fungal species were associated with high or low CO2 emission rates. In addition, as indicated by separate models for each tree species, forest management intensity, study region, and the water content as well as C and N concentration of dead wood influenced CO2 emission rates.

Increasing N deposition impacts neither diversity nor functions of deadwood‐inhabiting fungal communities, but adaptation and functional redundancy ensure ecosystem function

“…In this experiment, the original tree species significantly affected fungal diversity, community composition, enzyme activities and wood decomposition rates. This is expected and consistent with previous studies (Kahl et al ., ; Arnstadt et al ., ; Baldrian et al ., ; Purahong et al ., ; Noll et al ., ). Besides the general saprotrophs and white rot saprotrophs, which were frequently detected in most tree species, other functional groups such as plant parasites (broadleaf deciduous: Eutypa Otu_0028 and Pestalotiopsis Otu_0132; coniferous: Sporothrix Otu_0155), mycoparasites (broadleaf deciduous: Cuniculitrema Otu_0044) and ectomycorrhizal fungi (coniferous Clavulina Otu_0097) were also frequently detected in logs of some tree species.…”

“…to 1569 (P. sylvestris) (Bantle et al, 2014). More information about this deadwood decomposition experiment is published elsewhere (Kahl et al, 2015).…”

Tamm Review: Sequestration of carbon from coarse woody debris in forest soils

“…At the same time, our understanding of principles of stabilization of OM in soils has greatly increased and insights have been subject to change over the past 10 years (von Lützow et al, 2006;Marschner et al, 2008;Kalbitz and Kaiser, 2008;Schmidt et al, 2011;Dungait et al, 2012;Lehmann and Kleber, 2015). However, most studies on CWD have focused on the aboveground CWD-pool and respiration fluxes of C from CWD, using eddy-covariance and respiration chamber methods (Gough et al, 2007;Luyssaert et al, 2008;Ohtsuka et al, 2014;Kahl et al, 2015), rather than incorporating the effect of CWD on soil C pools. This in spite of the fact CWD may yield a larger dissolved organic C (DOC) flux to the forest soil per unit mass than foliar litter (Hafner et al, 2005).…”

Bacteria inhabiting deadwood of 13 tree species are heterogeneously distributed between sapwood and heartwood

“…The present work follows on from previous investigations using the same experimental platform – the BELongDead (Biodiversity Exploratories Long term Deadwood) experiment, which explores the process of decomposition in deadwood logs from 13 deciduous and coniferous temperate tree species with one starting point for decay (Bantle et al ., , b; Kahl et al ., ; Baber et al ., ; Noll et al ., ; Purahong et al ., , b). It has been shown that C, N and CO 2 release, enzyme activities and fungal diversity vary significantly between deadwood of different tree species, especially between deciduous and coniferous types.…”