The uptake of DNA based identification of freshwater macroinvertebrates in routine monitoring programs offers opportunities to investigate new metrics for assessing river health. Phylogenetic Diversity (PD), a measure of shared evolutionary history within communities, is one such metric and is expected to act as a surrogate for measuring multiple functional traits.
We retrofitted DNA barcoding data to 16 years of routine biological monitoring data of the Mitta Mitta River. Phylogenetic Diversity values were calculated for each sampling event using species level data from just two taxonomic orders, caddisflies and mayflies. These values were then compared to Family Taxa Richness and SIGNAL2 scores, calculated from family level data and including multiple orders. Our results showed that Phylogenetic Diversity was strongly correlated with both Family Taxa Richness and SIGNAL2. Family Taxa Richness correlated more strongly with PD than with SIGNAL2 score.
Our findings suggest that the health of the Mitta Mitta River could be assessed through PD metrics using genetic data from just two macroinvertebrate orders rather than through the current method of collecting and identifying specimens from across multiple orders.