On Monday we were on-site at Llyn Cwellyn to collect the sediment core sample for the palaeoecological study. It was a fantastic sunny day but a stiff breeze running the length of the lake made for challenging coring conditions. The expert team from the University of Liverpool did an amazing job to retrieve a great quality core, which probably represents several centuries of sediment deposition at Llyn Cwellyn.

Once the core was returned to the bank, the team meticulously sliced sediment layers at 1cm intervals which have now been returned to their laboratory.

Each sediment layer will be isotope dated and analysed to determine phosphorus concentrations and diatom species. Phosphorus is the primary driver of eutrophication and changes in diatom species composition are a strong indicator. We hope to publish the results of this study in late summer.

This study is being conducted as part of Prosiect Torgoch funded by The National Heritage Lottery. For further information or to ask any questions email: antony@northwalesriverstrust.org