Environmental drivers of fungal non-pollen palynomorphs in European temperate forest

Abstract

Fungal non-pollen palynomorphs (fNPPs) are increasingly recognized as valuable indicators in paleoecology, yet their ecological preferences in temperate lowland forests remain poorly understood. This study examines the environmental drivers shaping fNPP assemblages by assessing their relationships with key ecological gradients: forest type, ungulate pressure, canopy openness, and deadwood characteristics (coarse woody debris, snags, and stumps). Understanding these associations is critical for refining the use of fNPPs as indicators of forest structure, disturbance regimes, and ecosystem dynamics.

We analyzed fNPP assemblages from moss samples collected across structurally diverse forest habitats and applied multivariate analyses to determine their ecological affinities. The results indicate that medium ungulate pressure and variations in canopy openness significantly influence fungal community composition. Additionally, different types and volumes of deadwood provide key microhabitats for specialized fungal taxa, while saprotrophic and coprophilous fungi reflect organic matter decomposition and herbivore activity. Certain taxa also exhibited strong preferences for specific forest types, suggesting that fNPPs can indicate past moisture regimes, tree species composition, and forest dynamics.

These findings highlight the potential of fNPPs as proxies for past forest conditions, particularly in reconstructing herbivore activity, canopy structure, and wood decay processes. By linking modern fungal assemblages to environmental gradients, this study enhances the interpretation of fNPP records in paleoecology and provides a refined tool for reconstructing historical ecosystem processes and forest succession patterns.