Why people like or dislike large wood in rivers-a representative survey of the general public in Germany

For the restoration of medium and small rivers, the reintroduction of large wood (LW) is crucial. Despite the wide communication of the ecological key functions of LW, residents rejected its reintroduction in a restoration project at the river Mulde (Dessau-Rosslau, Germany). To determine whether this is a local or widespread phenomenon in Germany, we investigated (a) the German population's attitude toward LW, (b) preferred quantities of LW introduction, and (c) the effects of flood experiences and other sociodemographic characteristics on these preferences. We conducted a nationwide and representative online survey (n= 2,100), including rating-scale statements and a choice experiment (CE). Regarding the rating statements, we found that a majority of respondents (57-67%) is convinced of the advantages of LW reintroduction. However, 47-60% considered LW to be dangerous for canoeists or during floods. For the CE (n= 743), we defined an LW attribute and added information on possible effects. Conditional logit models showed a strong preference for the highest amount of LW, with an odds ratio 5.47 times higher than for the status quo without LW. We also found that personal flood experiences reduce the preferred LW quantities. In contrast, females, higher educational levels, the youngest and oldest age groups, and especially frequent river visitors preferred higher LW amounts. Since the commitment of young people to environmental issues is currently increasing, we believe that specific environmental education opportunities for this group located along the river can contribute significantly to increase acceptance.

Automated summary

The study showed that the majority of German participants believe in the benefits of reintroducing large wood, while some are concerned about its danger, especially for canoeists or during floods. Females, individuals with higher education levels, the youngest and oldest age groups, as well as frequent river visitors, tend to prefer larger quantities of large wood. With the increasing commitment of young people to environmental issues, setting up specific environmental education opportunities for this group along the river may significantly increase acceptance of reintroducing large wood.