What’s wrong with the Australian River Assessment System (AUSRIVAS)?

The Australian River Assessment System (AUSRIVAS or AusRivAS) is a national biomonitoring scheme that supposedly assesses the ‘biological health’ of rivers. AUSRIVAS outputs observed-over-expected (O/E) indices derived from macroinvertebrate survey data obtained both at site to be assessed and designated reference sites. However, sites lack any consistent quantified status, and, therefore, O/E have no particular meaning. Moreover, many studies found weak inconsistent indicator exposure anthropogenic human-influenced stressors. Poor performance by may relate numerous factors including following: (1) variable reference-site (2) inappropriate model predictors, (3) limitations indices, (4) inconstant sampling methods, (5) neglect non-seasonal temporal variability. Ephemeroptera–Plecoptera–Trichoptera (EPT) stream invertebrate grade number – average level (SIGNAL) provide alternatives often outperformed in comparative tests. In addition, bioassessment rivers might advanced development diagnostic methods identify stressors causing ecological impact rather than merely infer intensity assign quality ratings assessment