Riparian forests are among the most diverse terrestrial ecosystems, yet their biodiversity is increasingly
threatened by habitat degradation, climate change, river regulation and invasive species. We investigated
deadwood, widely recognized as an indicator for forest biodiversity, in riparian forests of the Mura-Drava-
Danube Transboundary Biosphere Reserve. The Biosphere Reserve is a conservation area that spans five countries
and three rivers located in south-eastern Europe. In detail, we analyzed the drivers of lying deadwood
volume, occurrence and decay related to floodplain type, silvicultural management, and climatic conditions
using regression models. Lying deadwood occurrence and volume significantly decreased as distance from the
river edge increased, indicating that river dynamics likely play a role in deadwood accumulation in riparian
forests. Deadwood volume was also positively influenced by stand basal area, a parameter that can be directly
addressed by silvicultural management. Deadwood decay was affected positively by temperature and negatively
by precipitation, highlighting the importance of climatic conditions on decay progression. However, in order to
draw more accurate conclusions about the drivers and dynamics of deadwood in riparian forests, further
monitoring efforts that consider river flooding and flow regime, deadwood transport and saproxylic organism
activity in addition to forest management and site conditions, are needed. Keywords: Alluvial forest, Hardwood floodplain, Deadwood decay, Mura-Drava-Danube Transboundary Biosphere
