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Shaver, Michael L.; Shannon, Joseph P.; Wilson, Kevin P.; Benenati, Peggy L.; Blinn, Dean W.

doi:10.1023/a:1003174517396

Cited by 26 publications

(1 citation statement)

References 25 publications

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“…Collier and Lill (2008) observed an increase in diversity at main channel sites with distance down river in a large New Zealand watercourse, most likely as a consequence of interplay between habitat patchiness and successional and hydrogeomorphic processes influencing macroinvertebrate community. In the middle Chubut river basin where turbidity and flood disturbance were high, benthic density was low as found below a tributary of the Colorado River in arid Arizona (Shaver et al 1997, Stevens et al 1997. In contrast, the upper main river channel and its tributaries had a more abundant benthic fauna and twice the number of species found in the middle basin.…”

Section: Discussionmentioning

confidence: 95%

Effects of flow regulation, basin characteristics and land-use on macroinvertebrate communities in a large arid Patagonian river

Miserendino

2009

Biodivers Conserv

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Longitudinal distribution and abundance of macroinvertebrate communities were examined in relation to hydrochemical variables along the Chubut River in the Patagonian Precordillera and Plateau, Argentina. The Chubut River ([1000 km) is the largest river in the area and its basin is subject to multiple uses: agriculture, cattle raising, urbanization and the hydrological regime of the lower section is modified by a reservoir. Quantitative benthic samples were collected at 13 sites in the higher, middle and lower sections of the river basin. Sites were visited four times during 2004 and physicochemical parameters, chlorophyll a and particulate organic matter (POM) were assessed. Ninety-five taxa were collected in the study, with total species richness per site ranging from 5 to 51, and benthos density averaging 299-5024 ind m -2 . Altitude and turbidity were implicated as important factors determining macroinvertebrate assemblages along the river system, and an eutrophication gradient was documented in the regulated/urbanized section of the main river. High turbidity (TSS) and sedimentation limited algal productivity in the middle basin. Below the dam, TSS, total phosphorus (TP) and POM decreased, whereas soluble reactive phosphorus (SRP) and chlorophyll a increased. Macroinvertebrate density increased three fold in this area possibly due to habitat improvement and enhanced trophic resources. Mean species richness did not change below the impoundment; however the community was dominated by gastropods, chironomids and flatworms. The Chubut River is complex and its biotic community reflects the landscape attributes. While benthic composition and density was governed by turbidity and flood disturbance in some river segments, a greater environmental heterogeneity resulted in an unexpected high number of species at the main channel upper basin.

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Section: Discussionmentioning

confidence: 95%

Effects of flow regulation, basin characteristics and land-use on macroinvertebrate communities in a large arid Patagonian river

Miserendino

2009

Biodivers Conserv

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Desiccation and recolonization of phytobenthos in a regulated desert river: Colorado River at Lees Ferry, Arizona, USA

Benenati

Shannon

Blinn

1998

Regul. Rivers: Res. Mgmt.

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We tested the recolonization of the phytobenthic community in the tailwaters of Glen Canyon Dam following long‐ and short‐term experimentally induced desiccation. The response of Cladophora glomerata, Oscillatoria spp., miscellaneous phytobenthos species and periphyton was studied over 18 weeks using three treatments: (1) undisturbed control cobbles from the submerged zone; (2) cobbles desiccated and replaced into the submerged zone; and (3) cobbles desiccated and replaced into the varial zone. Periphyton density and compositional response resulting from these treatments were also examined. Desiccation treatments were significantly different in biomass from controls throughout the study. The biomass of desiccated and replaced river cobbles averaged <30% of the controls for C. glomerata and periphyton during the 18‐week recolonization period. In contrast, the biomass of the control Oscillatoria and miscellaneous phytobenthos species averaged only 3 and 50% of that in the desiccation treatments, respectively. Cladophora, the dominant alga, comprised 77% of the phytobenthic biomass. A significant positive relationship between discharge, Cladophora and periphyton biomass was present in all treatments, while there was a negative relationship with discharge for Oscillatoria and miscellaneous phytobenthos species. There was a significant inverse correlation, as well as a pattern of separate biomass dominance, between C. glomerata and Oscillatoria. Cladophora was the dominant phytobenthos species on cobbles below the baseflow and Oscillatoria was dominant on cobbles in the varial zone. In general, the Cladophora biomass decreased under intermittent drying conditions, while Oscillatoria declined under permanently wet conditions. Diatom composition was not significantly different between treatments; however, their density was lower on desiccated cobbles. Diatom density on desiccated cobbles in the submerged and varial zones averaged 69 and 42% of that of the controls, respectively. Recovery and maintenance of benthic resources are hindered by fluctuating flow regimes driven by electricity and irrigation requirements. Repeated desiccation of the phytobenthos has major effects on the bottom‐up interactions in the Colorado River ecosystem. © 1998 John Wiley & Sons, Ltd.

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The Impact of Altered Flow Regime on Periphyton

Smolar-Žvanut

Klemenčić

2013

Ecohydraulics

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Untitled

Cited by 26 publications

References 25 publications

Effects of flow regulation, basin characteristics and land-use on macroinvertebrate communities in a large arid Patagonian river

Effects of flow regulation, basin characteristics and land-use on macroinvertebrate communities in a large arid Patagonian river

Desiccation and recolonization of phytobenthos in a regulated desert river: Colorado River at Lees Ferry, Arizona, USA

The Impact of Altered Flow Regime on Periphyton

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