Impact Assessment

 

Biomonitoring is a key component of environmental impact assessment because changes in biological communities are powerful indicators of ecosystem condition. Biomonitoring for impact assessment often focuses on invertebrate taxa on the grounds of high species diversity and short generation times, meaning that effects can be detected over relatively short time frames. However, invertebrates are challenging and time-consuming to identify (even for expert taxonomists), and this represents a costly bottleneck. Moreover, taxonomic expertise is a declining skill, meaning that identification is often carried out by non-specialists. Many taxa are overlooked or misidentified, and observer bias can be very high

 

DNA-based methods, particularly metabarcoding and metagenomics, allow species-level data to be gathered quickly, reliably, and cost-effectively across all invertebrate taxonomic groups. This means:

    1. Reduced cost to the end-user due to greatly reduced amount of labour required in samples processing
    2. Fewer specialists needed for routine identification
    3. Greater consistency across samples due to lack of observer bias
    4. Much faster turnaround times
    5. Improved chain of evidence since DNA can be stored long-term

 

Biomonitoring usually focuses on a suite of known indicator species. Using high-quality, curated reference databases, DNA-based methods can provide high-confidence detections of these species and may also be able to estimate relative abundance if a metagenomics approach is adopted. Additional insights and statistical power are gained at no extra cost through inclusion of non-indicator taxa.