Which indicator is commonly used in biological assessments to measure ecosystem health?

The use of macroinvertebrates as an indicator in biological assessments of ecosystem health is rooted in their sensitivity to environmental changes and alterations in water quality. These organisms, which include insects, crustaceans, and worms, are integral to aquatic ecosystems. Their presence, diversity, and abundance can provide substantial insight into the water body's ecological condition.

Macroinvertebrates respond predictably to various stressors such as pollution, habitat degradation, and changes in flow regime. For example, certain pollution-sensitive species may decline or disappear when water quality deteriorates, while pollution-tolerant species may thrive. This variance allows researchers to assess not just the current state of the ecosystem but also its history and ongoing health.

Additionally, the collection and identification of macroinvertebrates are relatively straightforward and cost-effective, making it practical for routine monitoring. Through these attributes, macroinvertebrates serve as a reliable ecological indicator, reflecting the overall health of the aquatic environment and helping to inform management and conservation efforts.