Tolerance Values and Effects of Selected Environmental Determinants on Caddisfly (Trichoptera) Distribution in Northwest and North Central Washington, USA

摘要: ABSTRACT. Caddisflies were collected at 181 wall seep, stream, river, and lake habitats in 7 counties northwest north central Washington over a 6-year period. From 17,405 specimens, we identified 164 adult caddisfly species within 62 genera 16 families. Twenty taxa new state records, bringing the number of currently reported from to 230. Species assemblages compared altitude, physicochemical factors, aquatic-habitats, land use (urban, agriculture, forest) on west east sides North Cascade Range. richness showed significant positive correlations altitude pH negative total phosphorus, nitrogen, specific conductivity, as well especially channel embeddedness. A multilevel hierarchical clustering model separated seeps, streams, rivers into geographic land-use regions based assemblages. We used multimetric index (caddisfly tolerance [CTI])...