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<br />e <br /> <br />e <br /> <br />Water quality impairment indicator groups <br /> <br />The presence, absence or relative dominance of a particular taxon or group of <br />taxa can provide information on the relative water quality at a site. Taxa were <br />labeled as pollution intolerant if they are known to occur primarily in unpolluted <br />waters. Pollution tolerant taxa are those known to be tolerant of fine sediment, <br />high water temperatures, or high organic loads. Tolerance values are shown in <br />the life history table. <br /> <br />Pollution Intolerant taxa <br />Intolerant mayflies - Mayflies are common in most waters and several taxa are ultra <br />sensitive to fine sediment, low dissolved oxygen, or high water temperatures. The <br />major pollution intolerant famlies are Ephemerellidae, Heptageniidae, and some <br />Baetidae. <br /> <br />Intolerant stoneflies - Most stoneflies are sensitive to changes in substrate <br />composition, water temperature, and retention of coarse organic matter (CPOM, <br />leaves, twigs). pteronarcys is a common stonefly which lives longer than 1 year <br />and is sensitive to changes in substrate and CPOM retention. Nemouridae are <br />common shredder stoneflies that are intolerant of organic loading and fine sediment. <br /> <br />Intolerant caddis flies - Intolerant caddisflies include the families Arctopsychidae, <br />Glossosomatidae, Philopotamidae, Psychomyiidae, and many Rhyacophilidae and <br />Limnephilidae. These families are widely distributed in most unpolluted waters <br />and prefer coarse substrates. <br /> <br />Corydalidae - Helgramites are long lived and sensitive to excessive fine sediment <br />deposition. Their presence indicates stable good habitat conditions. <br /> <br />Intolerant dipterans - Non-chironomidae dipterans which are intolerant of habitat <br />degradation. Taxa include Blephariceridae, Deuterophebiidae, Dixidae, <br />Pelecorhynchidae. <br /> <br />Intolerant Chironomidae - Includes members of the subfamilies Prodiamesinae, <br />Podonominae, and Diamesinae. <br /> <br />Intolerant molluscs - Hydrobiidae snails and Unionidae mussels have moderate <br />pollution tolerances. <br /> <br />Pollution Tolerant taxon <br />Tolerant mayflies - In contrast to many mayflies these taxa are tolerant of warmer <br />water, and higher fine sediment orgainc loads. Taxa include Tricorythodes, <br />Hexagenia, Caenis, Acentrella, and Baetis tricaudatis. <br /> <br />Tolerant caddisflies - Hydropsyche, Cheumatopsyche, hydroptilids, Helicopsyche, <br />Hesperophylax, Limnephilus, and some Leptocerids are tolerant of warmer water <br />and higher fine sediment levels. <br /> <br />Tolerant beetles - Agabetus, Carabidae, Helichus, Haliplidae, and many psephenids <br />and elmids are tolerant of warmer water, and higher levels of fine sediment and <br />nutrient enrichment. <br /> <br />Tolerant odonates - Most odonates are tolerant of warm water, high nutrients, <br />fine sediment, and dense communities of filamentous algae. <br /> <br />Tolerant dipterans - Antocha, Athericidae, ceraptopogonidae, Culicidae, <br />Dolichopodidae, Empididae, Ephydridae, Muscidae, Psychodidae, Stratimoyidae, <br />and Tabanidae are families which are typically abundant in waters with low habitat <br />integrity. <br />