DNA traces of organisms in environmental samples (soil, water, air, feces, saliva, etc.) are referred to as eDNA or environmental DNA. DNA metabarcoding can be used to determine the biodiversity of a habitat from the species or species groups detected in these samples. At the Thünen Institute of Forest Ecosystems, we are currently conducting two pilot studies to assess the potential of eDNA analyses for biodiversity monitoring in forests.

Pilot study 1: eDNA in tree microhabitats in the ADAPT-Wald-Holz project

Tree microhabitats are single tree structures on mostly older trees or standing deadwood on which various organisms are highly dependent during their life cycle. As trees with such structures in commercial forests were removed early in the past, such habitat, biotope or methuselah trees have become rare in many forests in Germany. Their occurrence is therefore often used as an indicator of high biological diversity in forests and is now promoted in many countries.

In the ADAPT-Wald-Holz project (link to project page: ADAPT-Wald-Holz), we take mulch substrate from cattle pockets and tree hollows of pines and birches and examine it for DNA traces of mammals, insects and fungi in order to determine the biodiversity that is actually present in certain tree microhabitats on site. In this way, we want to check whether existing tree microhabitats are actually used as habitats by rare species and can be used as indicators in biodiversity monitoring.

Pilot study 2: eDNA in precipitation water under tree crowns at the Britz intensive monitoring site

In addition, we are examining the precipitation water collected under the canopy and on the trunk at the Britz intensive monitoring site for DNA traces in order to determine the biodiversity in the tree canopy there and to assess the potential applicability of this method in forest environmental monitoring.