The LeDNA project developed a comprehensive framework to understand environmental DNA (eDNA) persistence and transport across different environmental states—cellular, membrane-bound, extracellular, and particle-bound. In vitro experiments with diverse species revealed that dissolved eDNA degrades fastest, while bacterial presence had minimal impact on degradation, challenging prior assumptions. Differences between plant and animal cells were negligible, though only dissolved DNA fit an exponential decay model. A novel study also revealed that microplastics may prolong eDNA stability by adsorbing DNA to their surfaces.
Fieldwork across eight lake catchments (237 samples) empirically separated eDNA into three states, showing that while dissolved and particle-bound eDNA have limited transport potential, membrane-bound DNA persists and can travel from streams into lakes—up to 40% of OTUs were shared upstream to downstream. Hydrological modelling of 217 inlets showed that eDNA reaches lakes within minutes to hours, although signals are less strong than expected, emphasizing the need to understand lake interface dynamics. Importantly, intracellular DNA is now confirmed as the most transportable state, with different states yielding unique biodiversity signals.
At the global scale, transport models indicated most of 1.4 million lakes could accumulate eDNA rapidly. A citizen science campaign sampled over 400 lakes across 121 ecoregions, covering over 6 million km². Initial analyses from 362 lakes detected over 87,000 OTUs, offering unprecedented biodiversity snapshots. Hypotheses about latitudinal diversity gradients are being tested, with early findings suggesting that DNA-based diversity patterns may differ from traditional expectations.
Technological innovations include a high-throughput qPCR multiplex system and a novel, patent-pending filtration device enabling global-scale, citizen-led biodiversity monitoring. Collectively, the project demonstrates how eDNA state separation, persistence studies, and transport modeling can transform biodiversity research and inform global conservation efforts under frameworks like the Kunming-Montreal Agreement.
