A monitoring showdown: Comparing morphological surveys and DNA metabarcoding

Abstract

Biodiversity monitoring is important for assessing and understanding the status and trends within the environment. Conventional vegetation surveys are commonly used for monitoring species diversity but they present several challenges for effective monitoring and management. Issues include the need for taxonomic field expertise, and difficulties in detecting cryptic and rare species and the phenological limitations on data collections. It is also often a time consuming and labour-intensive method of collection. To address and potentially overcome some of these challenges, novel genetic methods including community DNA sampling could allow scientists to overcome gaps in monitoring biodiversity. These methods can help overcome issues inherent in conventional field surveys by potentially providing a more comprehensive look at community composition.  The comparison between conventional and molecular approaches to monitoring vascular plant diversity in two different ecoregions captured different compositions of species. While molecular techniques are valuable, prior knowledge of survey sites and ecosystems are important for accurate results. Despite the potential advantages of genetic tools in diversity identification, morphological surveys remain relevant, providing essential observable field data that genetic tools are not capturing as we determined that communities monitored using genetic methods are not overlapping with surveying techniques. These tools are not yet suitable to replace conventional biodiversity monitoring.