A new salinity index for the invertebrate fauna of Australian inland waters

Abstract

Anthropogenic salinisation of inland waters worldwide causes diverse social, economic and ecological impacts, including shifts in the composition of biological communities. I used published data on occurrence of aquatic invertebrate taxa in relation to salinity to develop a novel Invertebrate-Based Salinity Index (IBSI) suitable for purposes such as indicating the ecological impact of anthropogenic salinisation and charting faunal recovery after salinity mitigation. Testing of the index with data independent of those used in its derivation showed a stronger association with salinity than prior Australian salinity indices based on macroinvertebrates. IBSI is applicable to both running and standing inland waters across Australia, and could be extended to other countries. Potential limitations of IBSI and its underlying salinity tolerance values are discussed, and suggestions are made for future index refinement and testing.