Metabarcoding data from a 36-month sediment trap time series and a sediment core in Cultus Lake, British Columbia

The use of DNA-based approaches in paleolimnology is gaining in popularity and has been proven to be effective to track some taxonomic groups in sediment records, mainly to track organisms that do no leave identifiable remains in the sediments. However, few studies have evaluated the congruence between morphological and DNA-based taxonomical identification as well as the to which extent the signal from the water column is traceable with DNA in sediment extracts. The 36-month sediment trap time series was developed to evaluate which DNA taxa can be deposited in the sediments and potentially be used as indicator taxa in paleolimnological studies. Congruence between morphological and DNA identification in water and sediment trap samples was also assessed specifically for diatoms and crustaceans. The sediment traps were deployed on a monthly basis in Cultus Lake, British Columbia, from July 2014 to June 2017. Water samples were collected for DNA extraction on each sediment trap deployment occasion. A fragment of the V7 region of the 18S rRNA gene was targeted to amplify micro-eukaryotes in general. In addition to metabarcoding data in sediment trap, water and core samples, the data include morphological counts for diatoms and cladocerans in the sediment traps. In addition, to evaluate the efficiency of DNA archived as intracellular and extracellular DNA in sediments to track past ecological dynamics, a sediment core was collected in May 2017 in Cultus Lake, British Columbia, to compare the changes identified from sedDNA to those identified with classical paleolimnological methods (i.e., geochemistry (delta 15N, delta 13C, % carbon, % nitrogen), pigments, diatoms, cladocerans). DNA was extracted from specific intervals of the sediment core and a fragment of the V7 region of the 18S rRNA gene targeting general micro-eukaryotes was sequenced. Data related to metabarcoding will be publicly deposited upon acceptance of the manuscript.