Taxonomic sufficiency: The influence of taxonomic resolution on freshwater bioassessments using benthic macroinvertebrates

摘要

Changing the taxonomic scale of a biotic-assemblage dataset influences our ability to detect ecological patterns.nIn bioassessments, a test-site’s biological community is compared against a benchmark to indicate ecosystem condition,nbut the taxonomic resolution needed to judge impairment reliably is the subject of much scientific debate. This paper reviewsntaxonomic sufficiency for freshwater benthic-macroinvertebrate bioassessments. Three main issues are discussed:n(1) the ecological significance of different taxonomic aggregations; (2) trade-offs involving taxonomic detail and informationncontent versus money, time, expertise, and data quality; and (3) sampling- and analytical-method-specific factors affectingntaxonomic sufficiency. Although Species should be the default taxonomic level for bioassessments, taxonomicnsufficiency is chiefly determined by a study’s purpose, and pragmatism often dictates reduced detail. When a taxonomicminimalismnapproach is necessary, a quantitative criterion for taxonomic sufficiency should be specified; this criterionnshould be based on an optimization of cost-benefit trade-offs associated with different taxonomic scales. Mixed-level aggregations,nas well as morpho-species and ecological-trait classifications should be considered in this optimization process.nLooking to the future, closer ties between taxonomists and bioassessment researchers would benefit both of their disciplines.nSuch coordination would provide the autoecological information and better diagnostic tools (such as keys and molecularnmethods) needed for biomonitoring, and better (and more widespread) biomonitoring would fuel taxonomy’snresurgence.