Abstract ID: 3.12911 | Accepted as Talk | Talk/Oral | TBA | TBA

Biodiversity is crucial for the functioning of healthy ecosystems, which are vital for human and animal wellbeing. However, it has been estimated that up to 40% of global insect diversity is in decline and at risk of extinction. Biodiversity declines have been associated with anthropogenic influences and can result in the loss of important species, such as pollinators, and the promotion of invasive species. The routine monitoring of biodiversity and its change in different terrestrial habitats is crucial to implement informed mitigation measures and long-term ecological research (LTER) sites play a key role in this process. However, the time and labour-intensive task and the expertise required to morphologically identify arthropod species hampers efforts to successfully employ biodiversity surveillance programmes. Molecular methods, more specifically the DNA-based identification of arthropods via metabarcoding of insect bulk samples and environmental DNA samples, have recently emerged as scalable and efficient biodiversity monitoring tools and are currently being implemented in the eLTER monitoring framework. Here, we showcase how DNA-based identification via metabarcoding can be used to assess arthropod diversity at Austrian LTER sites. We carried out a standardized flower washing technique, which captures trace amounts of environmental DNA (eDNA) left by plant associated arthropods and can be used as a minimally invasive monitoring approach in grassland systems. Sampling was done at seven locations (Alpine to lowland) monthly between Spring and Autumn in 2023 and 2024. At each site, 5 bouquets containing 30 flowering plants were vigorously washed in 350 mL of water which was subsequently filtered through a Sterivex™ filter and in total amounted to 391 eDNA samples collected from the seven sites. All samples were brought to the University of Innsbruck for extraction and subsequent eDNA metabarcoding for the detection of arthropod DNA. Preliminary results indicate a clear difference in arthropod communities between locations and over time. Our work highlights the applicability of DNA-based methods for monitoring Biodiversity at LTER sites and the potential of the minimally-invasive flower washing approach to answer questions related to biodiversity changes in ecosystems across Austria, thereby addressing a key component of the EU and Austrian biodiversity strategy 2030+.