The utility of DNA barcoding as a tool to assess the success of ecological restoration using Hemiptera as a biological indicator

DNA barcoding uses a short, standardized DNA fragment to sort individuals into species. This molecular technique has applications in fields including ecology, evolution, conservation, and biogeography. In ecological applications such as species monitoring and habitat restoration, its potential has not been fully realized and implemented. Invertebrates are excellent biological indicators, as changes in species diversity or community assemblage provide important insights into the condition of, or changes in, the environment. This information is particularly useful within the context of restoration ecology. In this study, DNA barcoding is used to assess the potential of Hemiptera as a biological indicator of restoration success for the Buffelsdraai Landfill Site Community Reforestation Project (Durban, South Africa). A total of 393 Hemiptera specimens were collected from sites reforested at distinct phases (plots reforested in 2010, 2012, and 2015) and two reference sites (natural forest and grassland). The Hemiptera species composition and assemblage were assessed by analyzing diversity indices, ordination, unweighted pair-group average cluster analysis, and phylogenetic analysis. Hemiptera species composition varied significantly across the chronologically different reforested sites, with a higher species richness observed in the older reforested plots. This suggests that Hemiptera diversity can be used to track restoration success, even over the small temporal scale used in this study. This study highlights the utility of DNA barcoding as a taxonomic sorting tool both to monitor ecological restoration and to discover specific taxa within Hemiptera that may be useful biological indicators.