Fungal Necromass and Black Carbon from Deadwood in Soil Carbon Cycling (FungiCarb)

• Applicants: Professor Dr. Bruno Glaser; Dr. Klaus Kaiser
• Subject Area: Soil Sciences ; Forestry ; Ecology of Land Use
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 568692286

Deadwood plays a fundamental role in forest ecosystems, providing a crucial substrate for biodiversity, particularly for saproxylic organisms such as fungi, bacteria, and arthropods. These decomposers drive nutrient cycling, influence soil properties, and contribute to the long-term sequestration of soil organic carbon (SOC). The decomposition of deadwood releases organic matter into the soil, triggering cascading effects on microbial activity, soil functioning, and carbon stabilization. The role of deadwood in enhancing SOC pools in forest ecosystems is still controversially discussed, and especially its potential contribution to the formation of stable SOC constituents, such as microbial residues (amino sugars) and black carbon, is poorly understood. Traditionally, black carbon has been attributed primarily to pyrogenic processes with incomplete combustion, such as wildfire. However, recent research, including own preliminary studies, suggests that fungal decomposition of deadwood may contribute significantly to black carbon formation. Certain melanin-producing fungi can stabilize C in biochemically resistant fungal pigments, which may persist in soils for extended time periods. However, the extent to which fungal necromass and associated pigments contribute to soil carbon stabilization across different deadwood types, degradation states, and environmental conditions is largely unexplored. Understanding these processes is critical for predicting long-term C storage in forest soils, particularly in response to different forest management intensities and tree species compositions. The Biodiversity Exploratories, and in particular the BELongDead experiment - an ongoing long-term study tracking deadwood decomposition since 2009- provide a unique opportunity to investigate the role of deadwood-decomposing fungi in stable C formation and sequestration. Covering multiple tree species, forest management regimes, and regional gradients, this long-term experimental platform allows for a comparative assessment of microbial-driven C stabilization. This project will integrate soil physico-chemical fractionation and molecular marker approaches to quantify the contributions of microbial necromass (amino sugars) and black carbon (fungal pigments) to SOC. By linking microbial processes to soil properties, decomposition rates, and tree species effects, this project will provide novel insights into the mechanisms driving long-term SOC stabilization in forest ecosystems.

• DFG Programme: Infrastructure Priority Programmes
• Subproject of: SPP 1374: Biodiversity Exploratories