Anthropogenic Disturbance and Environmental Associations with Fish Assemblage Structure in Two Nonwadeable Rivers

Abstract

Nonwadeable rivers are unique ecosystems that support high levels of aquatic biodiversity, yet they have been greatly altered by human activities. Although riverine fish assemblages have been studied in the past, we still have an incomplete understanding of how fish assemblages respond to both natural and anthropogenic influences in large rivers. The purpose of this study was to evaluate associations between fish assemblage structure and reach-scale habitat, dam, and watershed land use characteristics. In the summers of 2011 and 2012, comprehensive fish and environmental data were collected from 33 reaches in the Iowa and Cedar rivers of eastern-central Iowa. Canonical correspondence analysis (CCA) was used to evaluate environmental relationships with species relative abundance, functional trait abundance (e.g. catch rate of tolerant species), and functional trait composition (e.g. percentage of tolerant species). On the basis of partial CCAs, reachscale habitat, dam characteristics, and watershed land use features explained 25.0-81.1%, 6.2-25.1%, and 5.8-47.2% of fish assemblage variation, respectively. Although reach-scale, dam, and land use factors contributed to overall assemblage structure, the majority of fish assemblage variation was constrained by reach-scale habitat factors. Specifically, mean annual discharge was consistently selected in nine of the 11 CCA models and accounted for the majority of explained fish assemblage variance by reach-scale habitat. This study provides important insight on the influence of anthropogenic disturbances across multiple spatial scales on fish assemblages in large river systems. RightsWorks produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted. ABSTRACTNonwadeable rivers are unique ecosystems that support high levels of aquatic biodiversity, yet they have been greatly altered by human activities. Although riverine fish assemblages have been studied in the past, we still have an incomplete understanding of how fish assemblages respond to both natural and anthropogenic influences in large rivers. The purpose of this study was to evaluate associations between fish assemblage structure and reach-scale habitat, dam, and watershed land use characteristics. In the summers of 2011 and 2012, comprehensive fish and environmental data were collected from 33 reaches in the Iowa and Cedar rivers of eastern-central Iowa. Canonical correspondence analysis (CCA) was used to evaluate environmental relationships with species relative abundance, functional trait abundance (e.g. catch rate of tolerant species), and functional trait composition (e.g. percentage of tolerant species). On the basis of partial CCAs, reach-scale habitat, dam characteristics, and watershed land use features explained 25.0-81.1%, 6.2-25.1%, and 5.8-47.2% of fish assemblage variation, respectively. Although reach-scale, dam, and land use factors contributed to overall assemblage structure, the major...

Coupled fish-hydrogeomorphic responses to urbanization in streams of Columbus, Ohio, USA

“…To address the prediction that fish assemblages would reflect urban-induced shifts in hydrogeomorphic characteristics, relationships between hydrogeomorphic predictors and fish assemblage composition were initially investigated using canonical correspondence analysis (CCA) for 2011, 2012, and 2013 individually (package vegan [70] in R [71]). CCA is a common ordination technique to explore associations between environmental variability and biotic communities (e.g., [72]). Hydrogeomorphic predictor variables included in CCA were reduced to keep variance inflation factors (VIF; used to evaluate multicollinearity) < 10 [73] by alternately eliminating variables to best retain variation but reduce VIF, resulting in a set of PLOS ONE seven hydrogeomorphic predictors: width-of-floodprone area (m), sinuosity, incision ratio, entrenchment ratio, discharge (m 3 s -1 ), D 50 (mm), and slope (%).…”

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“…Rivers are important aquatic ecosystems supporting diverse life forms (Dudgeon et al, 2006) yet they are under intense anthropogenic disturbances such as nutrient enrichment via agricultural activities, urbanization (Parks, Quist & Pierce, 2014). In recent decades, there has been an increasing attention on the ecology of zooplankton communities in rivers regarding their abundance, diversity and spatio-temporal patterns (Lair, 2006).…”

Βιοποικιλότητα Και Βιογεωγραφικά Πρότυπα Των Ιχθύων Των Εσωτερικών Υδάτων Της Βαλκανικής Χερσονήσου

“…Position of the prey in the water column Mason et al 2008, Brind'Amour et al 2011, Pease et al 2015, Troia & Gido, 2015 Filtration or gill protection Mouillot et al 2005, Pease et al 2015 Mims et al 2010, Keck et al 2014, Pease et al 2015, Troia & Gido 2015, Parks, Quist & Pierce 2016 Age at maturation Mims et al 2010, Keck et al 2014, Pease et al 2015, Troia & Gido 2015, Parks, Quist & Pierce 2016 Total fecundity per spawining season per female Mims et al 2010, Keck et al 2014, Parks, Quist & Pierce 2016 Mean diameter of egg fully yolked ovarian oocytes Mims et al 2010, Pease et al 2015, Troia & Gido 2015 (Myers et al 2000).…”

“…Για παράδειγμα, ο Peres-Neto (2004) κατέληξε στο συμπέρασμα ότι η συνύπαρξη των ειδών των ψαριών σε Λειτουργική ποικιλότητα των ψαριών των εσωτερικών υδάτων και μείωση της πολυπλοκότητας στη σύνθεσή του. Η χρήση γης σε λεκάνες απορροής της Βόρειας Αμερικής έχει καταδειχθεί μεταξύ των σημαντικότερων παραμέτρων που διαμορφώνουν τη σύνθεση των ειδών με βάση τα λειτουργικά χαρακτηριστικά τους(Pease et al 2015, Parks, Quist & Pierce 2016.…”